2023 TWU Facilities Master Plan

WATER TREATMENT PLANT WATER FACILITIES MASTER PLAN

For the City of Tyler

Prepared by: Halff Associates, Inc.

Firm Registration No. 312

halff.com

Executive Summary

The City had previously contracted Halff Associates, Inc. (Halff) to build the water system inventory in GIS and provide an up-to-date set of tools to manage the current system more effectively and plan for the future. The scope of services for the Water Master Plan builds upon that previous study and includes the following:

• Water Distribution System Master Plan (separate report)

• Water Distribution System Asset Management Plan (AMP) (separate report)

• Water Treatment Plants Facility Plan, including Raw Water Supply Transmission Facilities

This report focuses on the City’s water treatment plants and associated raw water supply systems and provides a 25-year Capital Improvement Plan (CIP) for those facilities. For a WTP that has been in operation for many years, it is essential to consider rehabilitation and replacement of critical older equipment in the master planning process while also planning for future growth. Halff developed a list of the significant aboveground plant assets and below-ground piping and identified those areas/equipment needing immediate improvement or replacement. The asset inventory tables and maps are provided in Appendix A and aim to identify the major equipment and piping that may lead to a significant disruption in plant operation upon failure.

This report also reviews regulatory requirements for drinking water quality before evaluating the City’s Water Treatment Plants. TCEQ compliance is explained in addition to industry standards, which include taste and odor treatment. Geosmin is the primary culprit for taste and odor issues in the City, particularly water originating from Lake Palestine and processing through the Lake Palestine WTP. The report evaluates different geosmin treatment options and breaks down the costs associated with pursuing dual ozone-hydrogen peroxide setup that can remediate taste and odor issues during high geosmin periods.

Phasing expansion of water treatment facilities to accommodate future growth within the City is a subject of this report in addition to the Water Distribution System Asset Management Plan. This section of the report details how demand will be split between

the two WTPs over time, utilizing future expansion of the Lake Palestine WTP and a reformed version of the current Golden Road WTP. The option of an entirely new Southeast WTP is evaluated in this report as well, understanding that the merits of large capital investment in preferred infrastructure must be weighed against political and financial realities. This report adopts the financial constraints the City has expressed, prioritizing an option that keeps Golden Road in service. Each WTP is reviewed from its respective raw water intakes to the high-service pumps that direct the water to the distribution system, and elements of the production are identified for upgrades where necessary. This includes improvements such as enhanced geosmin treatment and replacing equipment that has reached its anticipated end of service life.

Ultimately this report produces a series of recommendations and an accompanying capital improvement program (CIP) based on estimates from real projects and non-binding quotes provided by manufacturers. The purpose of the CIP, found in Appendix I, is to enable the City to begin financially planning for these improvements and understanding which elements of the water system’s maintenance represent the greatest capital investment. A summary of the CIP projects is shown in Table ES.1 below. Elements included in the five-year improvement plan include the following:

• Lake Palestine geosmin treatment system– ozone generators, ambient monitors, and hydrogen peroxide dosing system. The existing contact diffuser expires in 2032 and will be replaced with a new side-stream model; the City may choose to make this upgrade early, alongside the five-year improvements listed here.

• Thorough evaluation of Golden Road that identifies all necessary upgrades to bring regular production at the plant up to its 28 MGD-rated maximum output. During its rehabilitation, electrical and mechanical upgrades shall be meticulously planned to minimize the operational impact on Golden Road.

Table ES.1: City of Tyler Proposed Water Facilities CIP

Note: The City has expressed intent to rehabilitate Golden Road Clariflocculators 3 and 4 by 2025. Their omission from this table is based on this understanding. All costs represent the present value.

1 The need, cost, and schedule of these projects are subject to change based upon the results of the Plant-Wide Assessment. The CIP should be updated once the assessment is complete and the results analyzed.

2 Timing of new High Service Pump Station is triggered by the City’s decision to start up the proposed Lower Pressure Plane

List of Figures

10 Figure 2.1 Ozone Contact Basin at Lake Palestine WTP

11 Figure 2.2 Rapid Mixers at Lake Palestine WTP

15 Figure 2.8 Filtration basins at Golden Road WTP

15 Figure 2.9 Ammonia containers at Golden Road WTP

16 Figure 2.10 Clearwells at Golden Road WTP

18 Figure 3.1 Raw Water Pumps at Lake Palestine Intake (left) and Lake Tyler Intake (right)

18 Figure 3.2. Ozone Generator (left) and Rapid Mix Unit (right) in Lake Palestine WTP

List of Appendices

Appendix A: WTP Asset Inventories

Appendix B: Facility Location Map and Process Flow Diagrams

Appendix C: SDWA Process Flow Diagram, Drinking Water Regulations, Drinking Water Quality Report

Appendix D: TCEQ Compliance at GR WTP and LP WTP

Appendix E: Additional Information about Geosmin and its Treatment

Appendix F: Geosmin Treatment Information and Costs

Appendix G: WTP Service Areas

Appendix H: Proposed WTP PFDs and Site Layouts

Appendix I: CIP Costs and Assumptions

Appendix J: Drone Survey

Appendix K: Documents Received From the City of Tyler

List of Abbreviations

• Ac [Acre]

• Action Level [AL]

• ASU [Arizona State University]

• Avg [Average]

• AMP [Asset Management Plan]

• AOP [Advanced Oxidation Process]

• ARJWS [Anderson Regional Joint Water System]

• BTEX [Benzene, Toluene, Ethylbenzene, and Xylene]

• BOM [Biodegradable organic Matter]

• CCI [Comprehensive Compliance Investigation]

• CEC [Contaminants of Emerging Concern]

• CIP [Capital Improvement Plan]

• CT [Concentration-Time]

• CWS [Community Water System]Serves 25 year-round residents or has 15 year-round service connections

• DO3 [Dissolved Ozone]

• DOC [Dissolved Organic Carbon]

• DBP [Disinfectant Byproduct Plan]

• DBPR [Disinfectant Byproduct Product Rule]

• DIP [Ductile Iron Pipe]

• EBMUD [East Bay Municipal Utility District]

• EPA [Environmental Protection Agency] - Federal agency responsible for the creation of water quality rules

• EPDM [ethylene-propylene-diene rubbers]

• EST [Elevated Storage Tank]

• ft [Feet]

• fps [feet per second]

• GIS [geographic information system]

• GAC [Granular Activated Carbon]

• gph [Gallons per hour of flow]

• gpm [Gallons per minute of flow]

• GR [Golden Road]

• HA [Health Advisory]- provide technical guidance on health effects, analytical methodologies, and treatment technologies associated with contaminants. HAs are not legally enforceable under SDWA but serve as technical guidance to PWS.

• HAA [Haloacetic]

• HAL [Health Advisory Level]

• HDPE [High-Density Polyethylene]

• HP [Horsepower]

• In [inch]

• LCR [Lead and Copper Rule]

• LCRR [Lead and Copper Rule Revisions]

• LCRI [Lead and Copper Rule Improvements]

• LP [Lake Palestine]

• LPUV [Low-pressure ultraviolet]

• LRAA [Locational running annual averages]

• LOX [Liquid Oxygen]

• MCL [Maximum Contaminant Level]

• MCGL [Maximum Contaminant Goal Level]

• MDBP [Microbial and Disinfection Byproducts]

• MTBE [methyl tertiary butyl ether]

• MIB [2-methylisoborneol]

• Min [Minimum]

• MG [Million Gallons]

• MGD [Million Gallons per Day]

• MCC [Motor Control Centers]

• NDMA [N-Nitroso-dimethylamine]

• NOM [Natural Organic Matter]

• NPDWR [National Primary Drinking Water Regulations]

• NTU [Nephelometric Turbidity Unit]

• O&M [Operation and Maintenance]

• OPCC [Opinion of Probable Construction Cost]

• PAC [Powdered Activated

Carbon]

• PFAS [Per- and Poly-Fluoroalkyl Substances]

• PFOA [Perfluorooctanoic Acid]

• PFOS [Perfluorooctane Sulfonic Acid]

• PPB [Parts Per Billion]

• PPD [Pounds Per Day]

• PPM [Parts Per Million]

• PS [Pump Station]

• PVC [Polyvinyl Chloride]

• PWS [Public Water Systems]

• RCP [Reinforced Concrete Pipe]

• RTCR [Revised Total Coliform Rule]

• RWPS [Raw Water Pump Station]

• Std [Standard]

• SDWA [Safe Drinking Water Act]

• su [Standard Units]

• SWMOR [Surface Water Monthly Operating Reports]

• SWTR [Surface Water Treatment Rule]

• TAC [Texas Administrative Code]

• TC [Total Coliform]

• TCEQ [Texas Commission on Environmental Quality]

• TCR [Total Coliform Rule]

• TPUC [Texas Public Utility Commission]

• TTHM [total trihalomethanes]

• TWDB [Texas Water Development Board]

• T&O [Taste and Odor]

• UCM [Uniform Costing Model]

• UCMR [Unregulated Contaminant Monitoring Rule]

• UV [Ultraviolet]

• USEPA [United States Environmental Protection Agency]

• USGS [United States Geological Survey]

• VOC [Volutile Organic Carbon]

• WEF [Water Environment Federation]

• WTP [Water Treatment Plant]

1. Introduction

The City of Tyler (City) owns and operates two water treatment plants (WTPs). The Golden Road WTP has a design treatment capacity of about 28 million gallons per day (MGD) and was constructed in 1951. This plant accepts raw water from Lake Tyler and Lake Tyler East via a raw water intake structure and pump station located at Lake Tyler. It is a rapid sand filter facility that uses sedimentation, flocculation, filtration, and disinfection. The Lake Palestine WTP has a current treatment capacity of about 30 MGD and was constructed in 2003. This plant accepts raw water from an intake structure and pumping station located on Lake Palestine. It is also a rapid sand filter facility that uses sedimentation, flocculation, filtration, and disinfection.

This report begins with a detailed background of both WTPs. It reviews how they integrate into the larger regional water supply as well as the technical ins and outs of their operation. It describes individual components and notes any relevant rehabilitation or upgrades the City has done. Following this background is an inventory of these components that assesses their condition and criticality to prioritize future improvements. It identifies piping and equipment that should be replaced immediately versus those that have not yet reached their end of service life.

The following two chapters review various regulatory requirements affecting the City’s water quality and how the City performs in comparison. This includes evaluating the Water Treatment Plants for overall compliance with TCEQ and industry standards.

This report then discusses geosmin, a chemical that causes taste and odor issues for the water supplied from Lake Palestine. This section details different treatment options, describes case studies of successful treatment, compares them to the existing treatment at Lake Palestine WTP, and ultimately recommends improving the current system.

The following chapter overviews how the City can expand its water treatment facilities to accommodate expected population growth. It identifies key capital improvements critical for growth and explores a schedule on which to undertake them. The final section of this report compiles the recommendations from previous chapters, clarifying which are proposed Capital Improvement Plan (CIP) projects and which focus on optimizing day-to-day operation and maintenance.

A series of appendices supplement this report. Digital deliverables provided to the City will include the asset inventory produced for this report and drone footage of each Water Treatment Plant.

2. Water Treatment Plant Background

The City of Tyler Water Utilities Department (TWU) is the primary finished water supplier for the City of Tyler (City) residents and commercial properties. TWU is also the wholesale provider for Whitehouse, Walnut Grove WSC, and Community Water Company. TWU also serves some Southern Utility customers. The City’s water utility service area, defined by the water Certificate of Convenience and Necessity (CCN) boundary, covers approximately 228 square miles, including 126 square miles of overlapping area with other water utility companies. The service area covered exclusively by the City is approximately 102 square miles.

The City has a population of approximately 106,000 people, according to the United States 2020 Census estimates. The majority of the City’s finished water distribution system is located within the city limits and is divided into seven pressure planes. This distribution system includes two water treatment plants (WTP), five elevated storage tanks (EST), one standpipe (SP), four booster pump stations (BS), and 708 miles of water mains. The EST, BS, and water mains are considered in the Water Distribution System Asset Management Plan.

TWU operates two WTP’s that provide the entire drinking water supply to all City customers. The Lake Palestine and Golden Road WTP operate under the Public Water Systems (PWS) ID No. 2120004. The location of the WTP, raw water lines, and intake structures are shown in Exhibit 2.1. Golden Road WTP is located in the central-east region of the distribution system, and treats surface water from Lake Tyler and Lake Tyler East. Lake Palestine WTP is located in the southwest region of the distribution system, and treats surface water from Lake Palestine. Upper Neches River Municipal Water Authority has water rights for Lake Palestine. The cities of Palestine, Tyler, and Dallas have contracts for supplies from Lake Palestine. The firm yield and water rights from these sources are shown in Table 2.1

Table 2.1: Water Rights and Firm Yield of Lake Palestine and Lake Tyler

1 Report on Water Supply, Population, and Water Use in Relation to Lake Tyler Water Rights Adjudication (1983)

2. Permit No 1843 TCEQ

3. City of Palestine, City of Tyler, and City of Dallas have contracts for supplies from Lake Palestine

4. Hydrology Report on Lake Palestine and Neches River Channel Dam and Reservoir (1984),

5. Available supply decreases to 189010 ac ft/year (168 MGD) by 2070

The following section briefly describes both plants’ existing WTP background, treatment units, and processes. Appendix B includes location maps and process flow diagrams of Lake Palestine and Golden Road WTP, respectively.

Halff conducted an initial site visit to Tyler WTPs on October 27th, 2020. The Golden Road and Lake Tyler intakes were visited on January 26th, 2021. Golden Road WTP was revisited on December 14th, 2021. While on the site visit, Halff communicated with the plant operators and inspected the treatment units and equipment. The information in the following section is based on the site visits, recent studies conducted in the WTP documents, and plans provided by the City on both WTP’s. Appendix K contains an inventory of the information received from the City to aid this study. Halff will deliver scanned images of this inventory as one of the project’s electronic deliverables.

2.1 LAKE PALESTINE WTP

The Lake Palestine WTP, rated for a treatment capacity of 30 MGD, was built in 2003. The 20-year-old surface WTP treats source water from Lake Palestine using raw water ozonation, coagulation, flocculation, sedimentation, and gravity filtration. The Lake Palestine WTP was intended to take more load from Golden Road WTP, and the City owns adequate property at this plant to accommodate a second 30 MGD treatment train. The presence and treatment of geosmin is a significant challenge at Lake Palestine WTP.

INTAKE:

The raw water at Lake Palestine is pumped to the treatment plant through approximately 9 miles of 54-inch ductile iron (DI) pipeline. The intake structure consists of a concrete platform that supports 3-1000 HP vertical turbine pumps (1 standby pump) with a capacity of 10,500 gpm each. The pumped water travels down the concrete bridge via a 48-inch DI pipe, which ties into a 54-inch underground discharge line initially constructed in 2003. Raw water in Lake Palestine can be withdrawn from a specific level associated with each pump based on information from record drawings:

◦ Pump 1: 323.5±0.5

◦ Pump 2: 328.5±0.5,

◦ Pump 3: 333.5±0.5

The raw water turbidity from Lake Palestine is typically less than 5 NTU. The lake has geosmin issues, in which levels climb from December to March. No chlorine or other disinfectant is added at the raw water source location.

ENTRY TO WTP AND OZONE CONTACT BASIN:

The 54-inch raw water line reduces to a 48-inch DI line 400 feet from the WTP. The raw water enters the WTP through a 48-inch diameter pipeline. The 12-inch recycle line joints the influent raw water line before reaching the ozone contact basins. Each ozone contactor is rated for 15 MGD. The basin has two parallel compartments, and ozone gas is applied to the raw water as it flows through the contact basin.

Ozone: Ozone acts as a disinfectant and oxidizing agent to reduce taste and odor issues. There is no set dosage that ozone is fed. It can range from 1.6 mg/l to a max of 6.0 mg/L. A typical range is 2.0 -3.5 mg/L, depending on the time of year and raw geosmin levels. Ozone dosage is increased during winter. The ozone generation building has two generators, and ozone is generated on-site from liquid oxygen stored in two 11,000-gallon tanks.

RAPID MIX:

The raw water flows from the ozone contact basin into a common open channel where powdered activated carbon is dosed. The raw water flows from here into the rapid mix basin with three parallel channels where alum and lime are dosed. Two mechanical mixers are within each compartment downstream and upstream equipped with variable frequency drives. Copper sulfate is seasonally dosed upstream of the common open channel.

Figure 2.1 Ozone Contact Basin at Lake Palestine WTP

Alum: Aluminum sulfate is used as a primary coagulant in Lake Palestine WTP. Alum dosage changes based on water quality conditions and jar test results. A typical range over the past few years is 48 to 56 mg/l. Alum is stored in liquid form as aluminum sulfate and fed through metering pumps.

Powdered Activated Carbon (PAC): Typically, PAC is dosed to control MIB and Geosmin-related taste and odor (T&O) events. Geosmin is present year-round from Lake Palestine; therefore, carbon and ozone are fed year-round. There is no set carbon dosage as the demand changes throughout the year. The dosage range is 5mg/l -42mg/l. PAC is fed at a lower dose during the off-season (April to November). Refer to Section 6.4 for additional information on the PAC unit.

Based on the site visit, it was understood that feeding the carbon system involves a lot of manual work. The remaining PAC in the super bag has to be continuously monitored. The PAC feed rate is adjusted weekly or more frequently during peak geosmin season based on the calculation tied to geosmin sampling of raw water feed. This sampling is conducted bi-weekly during non-peak geosmin seasons, and it takes $2,400 to test each sample. Currently, there is high operational and maintenance (O&M) cost associated with PAC.

Lime: Bulk pulverized lime is batched and mixed in a lime handling facility. Milk of lime solution is fed through metering pumps. Per a previous study, lime was dosed at 0.9mg/L. Lime is used to increase raw water alkalinity.

FLOCCULATOR:

Flow passes from rapid mix basin water to the sixflocculation basin. Each flocculation basin has three compartments with tapered mixing decreasing upstream to downstream. The gravity flocculation

basins provide sufficient mixing. However, the underground electrical conduits caused issues due to high humidity. Currently, aerial tray wires are being added to resolve this issue.

SEDIMENTATION:

From the flocculation chamber, water flows to the threerectangular sedimentation basin. Each sedimentation basin has three compartments with mechanical sludge scraping mechanisms and separate sludge blowdown boxes which run automatically. The sediment basins are taken out of service once a year. Cleaning is labor intensive and a considerable challenge due to the drain line outlet being seven feet off the floor. From the site visit, it was noticed that sedimentation basins have concrete cracks and leaks. However, according to discussions with staff, this does not cause significant operational problems. They described the leaking as “dripping at most” and blowdowns every three to four hours as sufficient to deal with drainage concerns. The settled water is dosed with free chlorine and filter aid polymer.

Figure 2.2 Rapid Mixers at Lake Palestine WTP

Figure 2.3 Flocculators at Lake Palestine WTP

Chlorine: Chlorine is fed from six one-ton cylinders as a gas and mixed with water for disinfection. There are six one-ton standby cylinders. Per a previous study, the flow through WTP was 16 MGD, and chlorine was fed at a rate of 840 pounds per day. The free chlorine dosage of settled water ranges from 5mg/l -18mg/l. The plant is equipped with four chlorine injection locations.

◦ Upstream of ozone contactor – Currently, not active

◦ Filters influent trough – Primary application point

◦ Downstream of filtration basins – Recent addition

◦ Finished water before clear wells – Currently, not active

Polymer: Filter aid polymer, aqualum, is added to the settled water trough. The filter aid was dosed at 0.8 mg/L.

operators on all filter control valves. The backwash system operates satisfactorily. Air scour system uses two blowers. During the site visit, air scour was an issue due to a suspected electrical issue or an issue with the PLC. Hence filter washing was done manually. The settled water from filters is dosed with ammonia. The backwash water from the filters flows to the twobackwash clarifiers. The liquid decant is recycled to the head of the plant before ozone contactors.

Ammonia: Ammonia is stored in a two-bulk pressure tank as liquid anhydrous ammonia. Two ammoniators (one duty, one standby) serve to meter ammonia. Ammonia is fed as a gas to the treated water downstream of the filters to form chloramine. The ammonia injection point in the plant was relocated based on a recommendation from a previous study to control total trihalomethane (TTHM). The chlorine-toammonia ratio was 3:1.

Sodium Hydroxide: The plant was initially designed to control pH using lime. Currently, lime is added only for alkalinity, and sodium hydroxide is used to control the finished water pH. The addition of sodium hydroxide reduces lead and copper concentration and helps produce finished water with the desired pH and alkalinity levels. Optimal pH of 8.8 to 9.2 is to be maintained in drinking water to maintain a strong monochloramine residual. The plant uses both 50% and 25% caustic dilution, dependent upon ambient temperatures throughout the year.

CLEAR WELL:

Lake Palestine WTP has two 2-MG clear well tanks to store finished water. The clear wells are covered to protect the sanitary conditions needed for potable water.

HIGH SERVICE PUMP STATION:

FILTRATION:

The clarified water flows through parallel pipes to eight-rapid sand filters. The heaviest filter loading is on the upper four filters (5-8) due to how the settled water channel feeds filters. The filter media consists of 12-inch sand and 24-inch anthracite. Filter media is 17 years old (beyond the recommended service life of 7 years) and is not currently a critical issue. However, the City has allocated funds to replace the filter media in 2024. Filter valves utilize pneumatic

There are four vertical turbine high service pumps equipped with variable frequency drive (VFD) in Lake Palestine WTP. The pump capacities are rated as 8680 gpm.

GENERATOR:

The raw water pump station generator is fully manual and supplies power to the raw water pumps. Lake Palestine WTP plant generator (2000 KW) is fully manual and supplies power to the plant, excluding the high-service pumps (HSPs). The high-service pump

Figure 2.4 Sedimentation Basins at Lake Palestine

generator (2000 KW) is fully manual and supplies power to all the HSPs. The generator (510 KW) at the administration building is automatic and supplies power to the building operations and administration.

2.2 GOLDEN ROAD WTP

The Golden Road WTP was built in 1951 and upgraded in 1965 and 1980. A new caustic chemical feed building was added recently, and there is a current project to refurbish existing filters. The plant was initially rated for a capacity of 32 MGD. The plant is currently rated at 28 MGD, and the typical production rate is 22 MGD. The 70-year-old conventional surface WTP treats source water from Lake Tyler using coagulation, flocculation, sedimentation, and gravity filtration. The Golden Road WTP was working during the winter storms in 2021.

INTAKE:

The raw water intake at Lake Tyler was built in conjunction with the WTP in 1951 and was further upgraded in 1978. This facility was replaced in March 1999 with a new intake and pumps equipped with VFD. The intake structure consists of a concrete platform that supports three 1250 HP vertical turbine pumps (one standby pump) with a capacity of 12,500 gpm each. The pumped water travels down the concrete bridge via a 42-inch ductile iron pipe. This line ties into 27-inch and 36-inch underground discharge lines. The 27-inch was constructed around the 1950s, and the 36-inch in 1964. The water from Lake Tyler is generally clean and free of geosmin. No chlorine or other disinfectant was added at the raw water source location.

ENTRY TO WATER TREATMENT PLANT AND RAPID MIX:

The surface water enters the plant through parallel raw water pipelines. Each raw water line discharges into an open channel at the head of WTP, into which fluoride, alum, and lime are being dosed. From the open channel, the raw water flows into the first-stage rapid mixer equipped with two electric mixers. From there, a short underground pipe conveys the flows into a second mixing basin where the lime slurry is dosed to boost the pH above 7 to 7.2 standard units (SU). The motorized mixer in the second mixing basin is operational only under certain circumstances.

Alum: Alum is purchased and stored as aluminum sulfate. Per a previous study, alum was dosed at 55 mg/L. Jar tests are conducted weekly to determine the optimum alum dose based on water quality.

Fluoride: Fluoride is added as hydrofluosilicic+acid, stored in bulk containers, and fed from a day tank using metering pumps. The natural fluoride in Lake Tyler (approximately 0.2-0.3mg/L) is supplemented by fluoride at the open channel in WTP to maintain a target concentration of approximately 0.7mg/L based industry accepted standards.

Lime: Bulk pulverized lime is stored in dry form and is batch mixed in the lime handling facility. The milk of lime solution is fed through metering pumps in the second stage rapid mixer to boost the pH above 7 to 7.2 SU. Per a previous study, lime was fed at the rate of 10mg/L. Optimal pH of 8.8 to 9.2 SU was required to maintain a good monochloramine residual in the distribution system. This led to the decision to add sodium hydroxide to address the issue.

Figure 2.5 Chemical containment and injection at Golden Road WTP

CLARI-FLOCCULATION:

Water from the rapid mix basin flows into four 110-foot diameter clari-flocculators with an inner compartment (flocculation well) and outer compartment (clarification zone). Clarifier #1, #2, and #4 flocculators have mixing-style flocculation devices, and the sludge rack is at the bottom of the tank. Clarifier #3 has large flocculation arms attached at the top of the mechanism and protrudes downward about 8 feet. The sludge rack also has arms that point upwards and mesh with the flocculator arms. The flocculators and sludge rack move in different directions and assist in forming floc. The clari-flocculator motors are not currently working. Free chlorine and polymer are added to the settled water flow junction box.

Polymer: Filter aid polymer, aqualum is added to the settled water flow junction box. The filter aid was dosed at 0.35 mg/L.

Chlorine: Chlorine is fed from six two-ton cylinders as a gas and mixed with water for disinfection. There are six two-ton standby cylinders. Per a previous study, the flow through WTP was 8 MGD, and chlorine was fed at a rate of 475 pounds per day. The free chlorine dose of settled water was 7.1 mg/L, with a measured free chlorine residual of 3.8 mg/L. The plant is equipped with four chlorine injection locations:

◦ open channel where fluoride and alum are dosed –currently not active

◦ clarifier influent flow splitter box – only active seasonally to remove algae from weirs of the clariflocculator weirs

◦ filters influent junction box – primary application point

◦ finished water leaving clear wells – typically used in the event of a power outage

Figure 2.6 Clariflocculators at Golden Road WTP

Figure 2.7 Chlorine containment and injection at Golden Road WTP

FILTRATION:

The Golden Road Plant has 16 rapid sand filters, and the current capacity of each filter is 1.5 MGD. The first four filters were constructed in the 1950s, and filter units were upgraded in future in 1978, 1993, and 2019.

point is located at the combined filter effluent piping. The backwash water from the filters flows to the backwash clarifier. The decanted water from the filter is transferred to City’s wastewater treatment plant and sludge to the sludge thickener unit.

Ammonia: Ammonia is stored in a two-bulk pressure tank as liquid anhydrous ammonia. Two ammoniators (one duty, one standby) serve to meter ammonia. Ammonia is fed as a gas to the treated water after chlorination to form chloramines. This compound will serve as a residual disinfectant for the clear well and the distribution system. Per a previous study, the free chlorine residual in settled water was 3.8 mg/L, and the free ammonia residual was less than 0.1 mg/L. The ammoniator dose was 1 mg/L. The chlorine-toammonia ratio of 3.8:1 is slightly lower than the optimal chloramination process. To reduce the formation of disinfectant byproduct (DBP), the ammonia injection point was relocated to combined filter effluent piping.

Filters four and five were rehabilitated recently, six and seven are currently rehabilitated, and eight will be rehabilitated in the future. Filters one, two, and three have also been rehabilitated. The 2009 Tyler Water System Master Plan states that the hydraulic capability of the filter piping system limits filter capacity. At a minimum, the filter+ media is to be replaced every ten years. However, the replacement schedule would only cycle through all 16 filters once every 40 years. An underdrain supports filter media. A new filter backwash system was installed in 2016 with two backwash pumps at 11,500 gpm each. The combined filter effluent flows to the clear well/high-service pump suction junction box. The ammonia and sodium hydroxide injection

Sodium Hydroxide: A caustic injector is installed on filters one through eight effluent lines in the existing manhole. A new caustic bulk storage and containment structure is built at the WTP.

CLEAR WELL:

Water from filters flows through a junction box where pH is monitored. From there, it flows into clear well for temporary storage, pumped directly by the high-service pumps to the distribution system.

pH Sensor: pH sensor is installed in the clear well/ high service pump suction junction box

Figure 2.9 Ammonia containers at Golden Road WTP

Golden Road WTP has two 2 MG clearwell tanks for finished water storage. The clear wells are covered to protect the sanitary conditions needed for potable water. Clear wells have new baffles, and a gentle swirl of flow within the tank helps with chemical mixing. Total chlorine is measured at clear wells.

HIGH SERVICE PUMP STATION:

There are six horizontal split-case high-service pumps in Golden Road WTP. The pumps have been rehabbed and repaired to different stages throughout the years. The pump capacities are as follows,

◦ Pump #1 – 4 MGD

◦ Pump #2, #3, and #4 – 8 MGD

◦ Pump #5 and #6 – 18 MGD

Based on the operation manual, pumps are used in different combinations to meet the demands.

Pumps #3 and #4 are not used simultaneously since the discharge line has a history of flow separation. Similarly, Pumps #5 and #6 are not used together. The pumps do not run if the clear well water elevation drops below ten feet. Thus, the pumps use only the top five feet of clearwell volume. Due to the high service pump station’s risk of flooding, flood-prone doors were installed recently.

GENERATOR:

Golden Road WTP and Lake Tyler intake do not have generators, and there is no emergency power backup for the intake and Golden Road WTP. A recent study at Golden Road WTP estimated a cost of $8 million to install generators and replace VFD.

Figure 2.10 Clearwells at Golden Road WTP

3. Asset Inventory Development

Tyler WTP assets were listed based on site visit notes, input from City personnel, photographs, record drawings, historical aerial imagery, and drone survey. This inventory list was used to document the ages, current conditions, and previous repairs and maintenance to identify areas and equipment needing immediate improvement or replacement. Exhibit 3.1 and 3.2 illustrates the assets considered for this study.

3.1 CONDITION

Asset condition was determined based on plant staff input, field observation, and equipment installation dates. A summary of this information and the reason for rating has been incorporated into the asset tables in Appendix A. Possible conditions were new, good, fair, and poor.

In the absence of input from staff or field observation, condition rating was based on criteria listed in Table 3.1. It should be noted that some of the installation years were assumed in the absence of data, as detailed in Appendix A. The staff can conduct more condition assessment work and revise this analysis if required. For all items, but particularly for the assets for which the installation year is assumed, it is recommended that the City performs a condition assessment to more accurately determine the condition of the pieces of equipment. Items were labeled “Poor” strictly based on the input from staff or field observation or if the asset exceeded its anticipated life. Refer to section 3.4 for more information on service life. The process of condition assessment is ongoing and should be performed on a routine basis.

Table 3.1 Criteria for Condition Rating

Anticipated Life) *100

Poor a) Based on the input from staff or field observation

b) Exceeding anticipated life

3.2 CRITICALITY

The criticality of each significant piece of equipment and each major pipe was also evaluated. The criticality scale and the condition of each piece of equipment should be used to determine the replacement priority for each item. If no major process units are shut down due to a pipe or piece of equipment failure, the plant can wait until it fails before replacing it without a significant interruption in operation.

An example of a noncritical failure would be if one of the pumps in the raw water pump station in Lake Palestine WTP were to fail. Since the pump station has redundancy, the plant can continue to operate without one of the pumps. However, more critical pieces of equipment and pipes will cause the entire plant to shut down upon failure. For instance, the 54-inch raw water line coming into Lake Palestine WTP is critical to the operation of the plant and should be replaced or rehabilitated before it fails. As failures of critical pipes or other critical pieces of equipment cannot be predicted, the plant staff should monitor the system closely for potential pipe or equipment failures as the end of their anticipated life approaches. Nondestructive testing may be performed on these critical items as they approach the end of their anticipated life to determine the estimated replacement timeline.

Close monitoring of these critical items will allow the plant staff to replace them before failure and avoid significant disruption in plant operation. Assets running parallel, such as pumps, were classified under ‘Shuts down no major process unit’ due to redundancy in equipment. However, a few of these units have been noted as out of service during the field visit, such as rapid mix unit 1 in Lake Palestine WTP. Thus, the plant staff should confirm the present condition of these assets and re-categorize the criticality if required.

Figure 3.1 Raw Water Pumps at Lake Palestine Intake (left) and Lake Tyler Intake (right)

Figure 3.2. Ozone Generator (left) and Rapid Mix Unit (right) in Lake Palestine WTP

3.3 CONDITION AND CRITICALITY RATING

Once the plant staff knows the criticality and condition of their major assets, they can monitor the high-risk items more closely than others and better prioritize replacement and rehabilitation projects. Figure 3.3 is a graphical comparison of asset condition to its risk. As illustrated in the figure, the resulting score based upon the simple multiplication of the condition rating times the criticality rating indicates the magnitude of replacement or rehabilitation urgency. In other words, the numbers in figure 3.3 represent an asset’s “risk points” if it falls in that square. Items in red need to be monitored the closest, followed by items in yellow. The plant should consider replacing or rehabilitating the items falling into the red category based upon a follow-on condition assessment, as appropriate. The items in red, yellow, and green categories are assigned risk ranks of 1 (high risk), 2 (moderate risk), and 3 (low risk), respectively, in Appendix A. The risk assessment of the sub-equipment items within the main asset could not be judged due to a lack of data. For example, since the condition and criticality of equipment in the electrical building were unknown, these were not included in this study. The plant staff can add any further information on these sub-units to the asset list. The categorization of risk scores and delineation of the color schemes are based on the engineer’s experience.

3.4 SERVICE LIFE

To estimate remaining service life, the current age of the major asset was determined either from design or record plans or from the previous replacement date as provided by plant staff. The plant staff reviewed the draft chapter and verified the installation dates. However, any discrepancy in the age or date of the installation based on the knowledge of equipment replacement should be updated.

Figure 3.3 Condition and Criticality Scale using Multiplying Method

Figure 3.4 Golden Road WTP Units Rapid Mix and Clariflocculator Basin

Filtration Basin and Chemical Storage Tank

Room

Table 3.2 and 3.3 lists the construction and maintenance dates of the WTPs. These dates are based on the design or record drawings, and the actual construction/installation dates could be marginally different from what is specified in the plans.

Average service life was determined for specific asset types from various industry sources. The remaining service life would be the current age subtracted from the average service life. Each evaluated equipment was placed into a category with a corresponding anticipated life. See Appendix A to see how each piece of equipment was categorized. Table 3.4 shows the assumptions used for the life of materials and equipment.

1 Water Environment Federation (WEF), Collection Systems 2010, p. 299

2 United States Environmental Protection Agency ( USEPA) Asset Management Training Workshop PowerPoint, Slide 119

3 The remaining are based on Engineer’s experience

Table 3.2 Golden Road WTP Construction and Rehabilitation Dates

Table 3.3 Lake Palestine WTP Construction and Maintenance Dates

The plant should take this information and build upon it by tracking its assets from this time forth. Whenever the plant purchases additional assets, the replacement cost and anticipated life of that asset should be documented in the GIS asset database. This documentation will assist the plant in planning for future replacements of assets. The plant staff should also include other items not included in Appendix A.

Figure 3.5 Lake Palestine WTP Units

a) Liquid Ozone System and Ozone Generation Building (top left), b) High Service Pump Station (top right), c) Filtration Basin (middle right), d)Sedimentation Basin (bottom)

3.5 RESULTS AND DISCUSSION

The plant should maintain and replace its equipment as it ages to keep the plant operating efficiently and within regulatory/permit limits. Figure 3.6 and 3.7 shows the number of major equipment items in each category in Lake Palestine and Golden Road WTP, respectively.

Per the figures, 21% of the documented assets in Lake Palestine WTP are in the high and moderate risk category (i.e., risk rank of 1 and 2). Whereas 54% of the documented assets in Golden Road WTP are in the high and moderate risk category. The relatively higher number of assets in the high and moderate risk categories in Golden Road WTP is due to the overall age of the plant.

The assets within each criticality rating are illustrated in Appendix A, Exhibits 3.3 and 3.4. The table presented in these exhibits lists the assets in the high and moderate risk categories and should be taken as a general idea of the future maintenance needs of the plant. The assumptions in Appendix A should be verified before the plant staff considers taking the next step of condition assessment and possibly replacing any equipment based on the categories. The items in the Table 3.5 appear to be the high-risk items for the plants and intakes. Exhibits 3.5 and 3.6 in Appendix A show the full raw water pipeline routes.

27-30” RC Raw Water Line

36-42” RC Raw Water Line

72’’ RC Standpipe 1

72” RC Standpipe 2

42” DI Raw Water Line (near intake)

48” DI Raw Water Line (near intake)

54’’ DI Raw Water Line

48’’ DI Raw Water Line (near WTP)

Figures 3.8 and 3.9 show the anticipated dates of equipment replacements in Lake Palestine and Golden Road WTP, respectively. It is a graphical representation of the number of equipment types anticipated to be replaced yearly. For example, from Figure 3.8, it can be inferred that in 2053, 14 process pipes, five civil units, and 27 miscellaneous mechanical equipment needs replacement in Lake Palestine WTP. In the same year, five civil units in Golden Road WTP need replacements, per Figure 3.9. The equipment replacement start date of 2021 in Figure 3.9 indicates

Figure 3.6 Individual Items in Each Category in Lake Palestine WTP

Individual Items in Each Category in Golden Road WTP

Table 3.5 Items in the high-risk category (red color)

that six pipes and four mechanical equipment have run into or exceeded their anticipated equipment life. Specific categories were combined, for example, scrapper, generator, and flocculator were combined into the miscellaneous mechanical category.

Figure 3.10 and 3.11 shows the anticipated dates for replacing lower-risk equipment (i.e., risk rank of three) ten years after the end of their anticipated life and high-risk items (i.e., risk rank of one and two) at the end of their anticipated life. Figure 3.8 illustrates

eight valves and two civil assets at Lake Palestine WTP to be replaced in 2033. However, since these assets were under the mild risk category, the replacement of these units could be delayed to 2043 (10 years post actual date of replacement), as shown in Figure 3.10. However, replacing the two valves in Lake Palestine WTP in 2033 is important since these assets are under the high to moderate-risk category. Similar inferences can be drawn for Golden Road WTP from Figure 3.11.

Figure 3.8: Equipment Replacement at the end of Anticipated Life for Lake Palestine WTP

Figure 3.9: Equipment Replacement at the end of Anticipated Life for Golden Road WTP

These figures, along with Exhibits 3.3 and 3.4, can be used by the City to help gauge the funding levels needed to perform necessary replacement/rehabilitation projects. Thus if there is a shortage of funds to replace all the assets in Figures 3.8 and 3.9 for a particular year, it could prioritize the replacement/rehabilitation work for the high and moderate-risk assets and rehabilitate the non-critical items ten years after the post-actual date of replacement as shown in Figure 3.10 and 3.11. This information should be beneficial for facility sustainability by making repairs proactively.

Figure 3.10: High & Moderate Risk Asset Replacement at the end of Anticipated Life and Low-Risk Asset Replacement 10 years after Anticipated Life for Lake Palestine WTP

Figure 3.11: High & Moderate Risk Asset Replacement at the end of Anticipated Life and Low-Risk Asset Replacement 10 years after Anticipated Life for Golden Road WTP

3.6 EQUIPMENT REPLACEMENT SCHEDULE

Appendix A prioritizes equipment replacement at both treatment plants based on the equipment age vs. the equipment’s anticipated life expectancy and criticality. The results identified several pieces of equipment nearing or past the end of their anticipated life expectancy. The equipment items anticipated to require replacement are listed in Tables 3.6, 3.7, and 3.8. This table shows equipment/units anticipated to need replacement in one year, five years, and ten years at Lake Palestine and Golden Road WTP. The equipment/units highlighted in red, blue, and green belong to high, moderate, and low risk, respectively.

Table 3.6: Equipment to be Replaced in 0 to 1 Year

*30-inch and 36-inch High-Pressure Lines reached their end-of-service life in 2021. This replacement project, however, is triggered by the City’s pursuit of a lower-pressure plane in the distribution system.

Table 3.7: Equipment to be Replaced in 1 to 5 Year

Table 3.8: Equipment to be Replaced in 5 to 10 Year

3.7 RECOMMENDATION

The following recommendations are made regarding this initial Asset Inventory for the Lake Palestine WTP & Golden Road WTP. The City should:

◦ Verify the actual age, criticality, and condition of assets, starting with those with the highest ranking in Appendix A. Any changes in condition from what was determined in this effort should be updated in the analysis. Condition assessment should be considered an ongoing effort since the condition does change over time.

◦ Monitor closely the performance and condition of assets ranked high in risk and are approaching the end of their useful life, particularly those in the red categories. Although the action may not be immediately necessary regarding these items, the plant, and future consultants can keep in mind the apparent weak points in the system. The goal would be to allow the replacement and/or rehabilitation of these assets quickly before their failure, which might lead to operational disruptions.

◦ Inspect the following raw water feed lines to determine the current condition. Based upon the condition assessment results, evaluate the need for pipeline rehabilitation or replacement, or update the remaining service life.

◦ 48-inch DI raw water discharge line from Lake Palestine pumps to upstream of the water meter. A major part of this pipeline is above ground.

◦ 54-inch DI raw water line upstream of the water meter to 54x48-in Tee Joint, 430 feet upstream of Lake Palestine WTP

◦ 48-inch DI raw water line from 54x48-in Tee Joint to Lake Palestine WTP

◦ 42-inch DI raw water discharge line from Lake Tyler pumps to the 27-inch to 36-inch tie-in location. A major part of this pipeline is above ground

◦ 36-42-inch RC raw water line to Golden Road WTP

◦ 27-30-inch RC raw water line to Golden Road WTP

◦ Inspect the following process lines to determine the current condition. The inspection could be prioritized based on the replacement year. Based upon the equipment replacement schedule results, evaluate the need for pipeline rehabilitation or replacement, or update the remaining service life.

◦ 24-inch DI Coagulated water in Golden Road WTP (Replacement Year: 2022)

◦ 33-inch RC Drain Pipe in Golden Road WTP (Replacement Year: 2022)

◦ 48-inch RC Clarified Water in Golden Road WTP (Replacement Year: 2024)

◦ 36-inch RC Coagulated Water in Golden Road WTP (Replacement Year: 2028)

◦ 30-inch and 36-inch High-Pressure Water Lines in Golden Road WTP (Replacement Year: 2021)

◦ Inspect the following equipment/units to determine the current condition. The inspection could be prioritized based on the replacement year. Based upon the equipment replacement schedule results, evaluate the need for equipment rehabilitation or replacement, or update the remaining service life.

◦ Ozone Generators 1 and 2 in Lake Palestine WTP (Replacement Year: 2023)

◦ Clariflocculator Basin 2 in Golden Road WTP (Replacement Year: 2025)

◦ Clear Well 1 in Golden Road WTP (Replacement Year: 2025)

◦ Raw Water Meter in Lake Palestine WTP (Replacement Year: 2031)

◦ 16-inch Surge Anticipator Valve in Lake Palestine WTP (Replacement Year: 2031)

◦ 16-inch Surge Relief Valve in Lake Palestine WTP (Replacement Year: 2031)

◦ 12-inch Surge Anticipator Valve in Golden Road WTP (Replacement Year: 2029)

◦ 12-inch Surge Protector Valve in Golden Road WTP (Replacement Year: 2029)

◦ Raw Water Meter in Golden Road WTP (Replacement Year: 2029)

◦ 1st and 2nd Stage Mixers in Golden Road WTP (Replacement Year: 2021)

◦ High Service Pumps in Golden Road WTP (Replacement Year: 2022)

◦ 72-inch Standpipes supporting Golden Road WTP (Replacement Year: 2022)

◦ Update the listing in Appendix A, Asset Inventory, into GIS as new equipment is installed or rehabilitation or replacement is conducted on existing assets. Also, include existing assets that are not in Appendix A.

◦ Special consideration should be given to rehabilitation/replacement recommendations for the Golden Road WTP. Subsequent sections of this report recommend eventually abandoning the existing plant and replacing it with a new one at a different location. So before proceeding with renewal projects at Golden Road, consideration

should be given as to the necessity of those projects given the likely short remaining life of the existing plant.

◦ After executing its planned filter media replacement at Lake Palestine in 2024, the City should evaluate any performance differences in the next five years. The basins currently use their original filter media, which has served over twice its target life cycle. The City should establish a regular schedule on which to replace the filter media based on the manufacturer’s recommendations.

◦ According to staff, the sedimentation basins at Lake Palestine WTP do not have significant operational problems due to its cracks and leaks. While periodic blowdowns are currently sufficient for the plant’s needs, the City should consider having an engineer evaluate the structure’s integrity and determine an appropriate time to pursue its repair or replacement.

4 Regulatory Requirements for Drinking Water Quality

Drinking water quality standards ensure that water collected, treated, and distributed by a public water system (PWS) is safe to consume. Environmental Protection Agency (EPA) is an agency of the United States federal government tasked to set and enforce a minimum national drinking water standard. EPA authorizes Texas Commission on Environmental Quality (TCEQ) to implement the safe drinking water act in Texas. It is responsible for ensuring the compliance of a system with TCEQ rules, conducting required monitoring, and providing public notifications. TCEQ has published the drinking water standards governing drinking water quality in Chapter 30, Texas Administrative Code (TAC) Chapter 290, Subchapter F. The City is authorized to treat raw water from Lake Palestine WTP and Golden Road WTP following the current regulatory requirements. The section below describes the drinking water regulations recently updated and/or anticipated for revision in the future with respect to drinking water quality aspects.

4.1 SAFE DRINKING WATER ACT (SDWA)

SDWA was formulated in 1974 to protect public health by regulating the public drinking water supply. It was amended in 1986 and 1996. The 1996 amendments greatly enhanced the existing law by recognizing the importance of protecting water from the source to the tap. Source water protection, operator training, funding for water system improvements, and public information were added as components of SWDA. The general flow of the SDWA regulatory process is outlined in Appendix C, as is a summary of the regulations described below.

4.2 LEAD AND COPPER RULE (LCR) BACKGROUND

Exposure to lead and copper may cause adverse health effects such as stomach distress to brain damage. The recommended exposure level of lead is zero for children. Lead typically enters drinking water when lead and copper plumbing materials, commonly used before 1986, begin to corrode. Lead

is subject to a treatment technology standard rather than a maximum contaminant level (MCL). The LCR was published in 1991 by the EPA to control lead and copper in drinking water.

EXISTING RULE

The treatment technique for the rule necessitates systems to monitor drinking water at customer taps. If 10% of the samples exceed the action level (AL) of 15 parts per billion (ppb) and 1.3 parts per million (ppm) of lead and copper, respectively, additional actions such as corrosion control treatment, source water monitoring and treatment, lead service line replacement, and public notification must be undertaken. Additionally, the samples should be monitored every six months after the corrosion control techniques have been initiated or optimized. However, the frequency of monitoring can be reduced if systems continuously meet AL.

CITY FINDINGS

According to the City of Tyler 2020 Drinking Water Quality Report, the water system is below the action limit for lead and copper. Before 2012, the lead and copper samples were collected triennially. For failing to take lead and copper tests in 2014, the City of Tyler received a “Notice of Violation” in 2014 and was required to submit a “Public Notice” in January 2015. Tyler water system was below the action limit for lead and one-tenth over the action limit for copper, according to the 2015 lead and copper sampling suite results. Old households in the City have lead fittings. The City’s Water System has complied with the lead and copper rule since 2016. Refer to Appendix C for the detailed report. The City conducted a water system corrosion control study on September 2020 in response to the letter from TCEQ. Tyler currently utilizes pH treatment in the form of sodium hydroxide (caustic) to control corrosion within the City’s water system.

PROPOSED RULE

The lead and copper rule revisions (LCRR) took effect on December 16th, 2021. The four major improvements in the rule are provided below.

Trigger Level (10 ppb) vs. Action Level (15ppb)

The rule maintains a 15 ppb action level but establishes a new threshold of 10 ppb, which, when exceeded, requires rapid corrosion control treatment to reduce lead in drinking water. The systems that currently treat for corrosion would be required to re-optimize their existing treatment at this trigger level. Alternatively, systems that do not treat for corrosion will conduct a corrosion control study, which aids the system in responding quickly when necessary.

The current rule emphasizes corrosion control to protect against lead and prepares systems for soluble and particulate lead. Improved corrosion control will improve protection against soluble lead, whereas service line replacement will reduce particulate lead.

Monitoring Testing and Notification

Under the current revision, the EPA proposes improving sample collection procedures, sample site location, monitoring frequency, and public notification. If a sample collected is above AL, water systems should notify the homeowners within 24 hours. Additionally, the EPA requires community water systems to test for lead in drinking water in elementary schools and childcare facilities. The tap sampling plan must be complete by October 16th, 2024.

Public Inventory

The rule requires local governments and water systems to create a public inventory of lead service lines. This helps to determine areas likely to have lead-contaminated drinking water needing remediation. A find-and-fix assessment is initiated if LCR compliance sampling at an individual home produces a result of 15 parts per billion (ppb). The lead service inventory must be submitted by October 16th, 2024.

Lead Service Line Replacement

As per the current EPA proposal, if a customer replaces the customer-owned portion of the line, the water system owner will have to replace the

system-owned portion of the lead service line. The proposal requires systems to replace a minimum of 3% of lead lines annually if the action level is exceeded. Systems above 10 ppb but below 15 ppb must work with the state to set an annual goal for lead line replacement.

CURRENT STATUS

The full compliance date for LCRR is proposed as October 16th, 2024. The two actions water systems must complete by the compliance date are the lead service line replacement and tap sampling plans. Additionally, EPA proposed to develop a new rule, the Lead and Copper Rule Improvements (LCRI), to reinforce the regulatory framework. The final action date for LCRI is scheduled before October 16th, 2024.

4.3 PERCHLORATE BACKGROUND

EPA started rule-making to establish perchlorate regulation in 2008. In 2009, the EPA published an interim health advisory of 15 µg/L for perchlorate and, in 2011, decided to regulate perchlorate in drinking water. Since 2011, EPA has found that perchlorate levels in drinking water supplies have declined due to actions taken by the EPA, states, and local communities, including reducing sources of perchlorate contamination and improving water system operations. The EPA published a notice of proposed rule-making for perchlorate in drinking water in the Federal Register in June 2019. The EPA proposed setting the MCL and Maximum Contaminant Goal Level (MCGL) at 0.056 mg/L (56 µg/L). The treatment technologies demonstrated to be effective in reducing levels of perchlorate are anion exchange, biological treatment, reverse osmosis, point of use, and point of entry reverse osmosis.

CURRENT STATUS

On July 21st, 2020, the EPA made a final action regarding the regulation of perchlorate under the SDWA. The EPA determined that perchlorate does not meet the criteria for regulation under the SDWA considering the available science and positive steps that EPA, states, and public water systems have taken to reduce perchlorate levels. Therefore, the agency is withdrawing the 2011 regulatory determination. The EPA is making a final determination not to issue a national regulation for perchlorate.

4.3 STRONTIUM BACKGROUND

In October 2014, the EPA preliminarily determined to regulate strontium in drinking water. Strontium can impact bone strength in people who do not consume enough calcium.

EPA set non-regulatory health advisory levels for strontium for one-day, ten-day, and lifetime duration. The health advisory threshold for the one-day and ten-day duration is 25,000 µg/L. The health advisory threshold for lifetime exposure is 4000 µg/L per the EPA 2018 Edition of Drinking Water Standards and Health Advisories Tables.

CURRENT STATUS:

On January 4th, 2016, the EPA delayed the final regulatory determination on strontium to further review data and determine if there is a meaningful opportunity to reduce health risks by regulating strontium in drinking water.

4.4 REVISED TOTAL COLIFORM RULE (RTCR) BACKGROUND

Coliform is bacteria found naturally in the environment and utilized as a marker for the presence of other potentially hazardous bacteria or a potential channel for contamination to infiltrate the drinking water distribution system. The presence of E. coli could indicate contamination, resulting in diarrhea, cramps, nausea, headaches, or other symptoms.

EXISTING RULE

The Total Coliform Rule (TCR) formulated in 1989 set both an MCGL and MCL for the presence of total coliforms in drinking water. MCGL level is at zero, and MCL levels are based on the positive sample tests for total coliforms (monthly MCL) or total coliforms and Escherichia coli (E. coli) or fecal coliforms (acute MCL). The purpose of the 1989 TCR was to monitor microbial contamination, such as total coliforms, in the drinking water system and protect public health by ensuring the integrity of the drinking water distribution system.

CITY FINDINGS

Refer to Appendix C for the City of Tyler Drinking

Water Quality Report from 2013 to 2020. Although two samples collected in 2020 tested positive for E. coli., the resamples tested negative. The MCL for Total Coliform Bacteria was exceeded in October 2020, and the repeated test results were negative. Level 1 assessment was executed by the City, and TCEQ accepted the City’s Assessment identifying no sanitary defects in the City of Tyler’s Public Water System. Additionally, the City conducted a level 1 assessment and adopted the corrective action in 2017 due to the presence of coliforms.

REVISED RULE

On February 13th, 2013, EPA published the Revised Total Coliform Rule (RTCR) in the Federal Register (78 FR 10269). The rule took effect on April 1st, 2016. This revision focuses on a preventative approach (“Find and Fix) rather than a response based.

RTCR specified the frequency and timing of microbial testing based on the system-specific sampling plan for total coliforms and the population served. Systems must assess Level 1 or 2 based on the triggers of the treatment technique.

Level 1 Trigger:

◦ If testing 40 or more samples per month, the system exceeds 5% total coliform-positive sample

◦ If testing fewer than 40 samples per month, the system has two or more total coliform positive sample

◦ Fails to monitor with all repeats after a Total Coliforms (TC)+

Level 1 Assessment:

The basic examination of the water system to try to identify the cause of TC+ samples such as examination of source, treatment system, distribution system, operational practice, sampling location, and procedure

Level 2 Assessment Trigger:

◦ E.coli MCL violation

◦ Second Level 1 trigger in 12 months

◦ Level 1 trigger in 2 consecutive years

Level 2 Assessment:

In-depth examination of water system source, treatment system, distribution system, operational practice, sampling location, and procedure

Treatment technique violations occur when an assessment is triggered and fails to timely complete the assessment or corrective action. Severe violations are based on a positive E.coli when a repeat sample is E.coli following a Total Coliform positive routine sample or a system fails to test for E.coli when any repeat sample is TC+. Systems must measure disinfectant residual at least at the exact location and time as total coliform samples are sampled.

4.5 CYANOTOXINS BACKGROUND

Cyanobacteria found naturally in surface waters can produce cyanotoxins under certain conditions that pose health risks to humans, such as musty taste and smell, gastroenteritis, liver damage, and kidney damage. Conventional water treatment (coagulation, sedimentation, filtration, and chlorination) can remove intact cyanobacterial cells. However, this can pose challenges to the water treatment system during a severe bloom event. The selection of effective treatment procedures depends on the growth patterns and species of cyanobacteria.

In 2015 EPA released an algal toxins health advisory for cyanotoxins, cylindrospermopsin, and microcystins, as shown in Table 4.1. Health Advisory describes concentrations of drinking water contaminants at which adverse health effects are not anticipated to occur over specific exposure durations (e.g., one day, ten days, several years, and a lifetime).

CURRENT STATUS

EPA did not propose any regulatory determination regarding cyanobacteria or cyanotoxins. The unregulated Contaminant Monitoring Rule (UCMR 4) includes an assessment of nine cyanotoxins and one cyanotoxin group, such as microcystin, nodularin, anatoxin-a, and cylindrospermopsin. Based on this assessment, the limited occurrence of cyanobacteria did not justify the need for national regulation.

CITY FINDINGS

The City detected the unregulated contaminant Anatoxin-a in the year 2018 and 2019. Refer to Appendix C for the City of Tyler Drinking Water Quality Report from 2013 to 2020.

4.6 SURFACE WATER TREATMENT RULE (SWTR) BACKGROUND

The SWTR protects the PWS from pathogens, such as Giardia lamblia, Legionella, and Cryptosporidium, and contaminants that can arise during drinking water treatment. These microorganisms can induce gastrointestinal disease if consumed. The SWTR emphasize treatment techniques instead of MCLs for microorganism.

EXISTING RULE

This SWTR is a combination of rules designed to protect from microbial pathogens and applies to all PWS using surface water. A minimum of three and four log removal of Giardia and Virus are required per this rule. The disinfectant contact time requirements are shown in Table 4.2.

Cyanotoxin Health Advisory

4.2: Disinfection Contact Time Requirement

4.7 FILTER BACKWASH RECYCLING RULE (FBRR)

This rule applies to all systems using conventional or direct filtration treatment that recycle spent filter backwash water, thickener supernatant, or liquids from the dewatering process.

Treatment technique requirement: All recycle flows must be returned at the head of the plant so that complete treatment of recycle stream is provided.

Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR)

This rule applies to all PWS using surface water. Treatment efficacy is demonstrated by combined effluent turbidity ≤ 0.3 Nephelometric Turbidity Unit (NTU) measured at conventional and direct filtration units in 95% of monthly measurements. The maximum turbidity limit is 1NTU. If the PWS meets filtered water turbidity criteria, it is assumed to achieve the required 2-log Cryptosporidium removal.

Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR)

This rule applies to all PWS using surface water. Monthly monitoring of Cryptosporidium for two years is required to characterize the source water. Calculated Cryptosporidium concentration defines the required level of additional treatment.

CITY FINDINGS

The City has met all turbidity requirements since 2013. Refer to Appendix C for the turbidity results from the City of Tyler Drinking Water Quality Report from 2013 to 2020. Additionally, Halff analyzed the surface water monthly operating report for both WTPs from June 2021 to November 2021. The treatment plant’s performance on turbidity, disinfectant residual, pH, and TOC removal requirements was within acceptable standards. Cryptosporidium is found only in the City’s untreated water as the treatment process removes cryptosporidium.

CURRENT STATUS

EPA identified 8 National Primary Drinking Water Regulations as candidates for revision at the 3rd 6-year review in January 2017. A few of the eight candidates are Cryptosporidium, heterotrophic bacteria, Giardia lamblia, Legionella, and viruses.

The EPA determined that new information on health effects, treatment technologies, etc. requires a detailed analysis of the SWTR and its components. The EPA is currently seeking public comments. No regulatory decision has been made regarding these contaminants. The schedule for the draft and final rules are proposed to be out by July 2024 and September 2027, respectively.

4.7 DISINFECTANT/ DISINFECTION BYPRODUCT RULE BACKGROUND

Disinfection of potable water is critical to protect the public from disease-causing microorganisms. The reaction between naturally occurring materials found in untreated drinking water and disinfectants such as chlorine and ozone produces disinfection byproducts. Some of these cause short and long-term health effects. Out of the hundreds of disinfectant byproducts formed in drinking water, total trihalomethanes (TTHM), five haloacetic acids (HAA5), bromate, and chlorite are regulated by the EPA.

EXISTING RULE

The EPA has developed DBPR to protect public health by limiting exposure to disinfectant byproducts. The DBPR is part of the Microbial and Disinfection Byproducts Rules (MDBPs). The stage 1 disinfectant byproduct rule, formulated in 1998, applies to all Community Water Systems (CWS) and reduces drinking water exposure to disinfection byproducts. The compliance is based on the annual arithmetic average of monthly averages. The stage 2 DBPR formulated in 2005 applies to CWS that adds a primary residual disinfectant other than UV or delivers water that has been disinfected. The DBP-2 rule requires systems to conduct an initial distribution system evaluation to determine the highest-risk sample sites for DBPs in the distribution system. Based on this rule, compliance has to be calculated at each sample site individually using locational running annual averages (LRAA) contrary to a system-wide average. PWS are more likely to experience water compliance issues under DBP-2 compared to DBP-1 since distribution issues such as water age can increase locational THMs and / or HAA5s.

The SDWA sets Maximum Residual Disinfectant Levels for chlorine (4 mg/L), chloramines (4 mg/L), and chlorine dioxide (0.8 mg/L) and set MCLs for four disinfection byproducts: (1) TTHMs (0.08 mg/L), (2) HAA5 (0.06 mg/L), (3) bromate (0.01 mg/L), and (4) chlorite (1.0 mg/L).

CITY FINDINGS

Compliance is evaluated quarterly, based on locating running annual averages from the City’s eight current compliance monitoring sites. The City has recently experienced intermittent periods of noncompliance with DBPR. Appendix C shows the City has received Notices of Violation for exceeding the maximum contaminant level for THM in the 1st quarter and HAA5 in the 1st and 2nd quarters of 2016 and 3rd and 4th quarters of 2015. The City’s Water System has complied with the DBPR rules since 2017 (Refer to Appendix C for the detailed report). The City detected the unregulated contaminants N-Nitrosodiethylamine, Bromodichloromethane, Bromoform, Chloroform, and Dibromochloromethane in 2017 and 2016 per the drinking water quality report. Also, HAA5, HAA6Br, HAA6, and Manganese were detected from 2018-2020.

In 2015, eHT completed an operational evaluation of the WTPs and identified potential improvements for continued compliance to DBPR. Table 4.3 summarizes the WTP’s initial and potential compliance strategies and status. Refer to Initial Operational Evaluation Report (eHT, 2015) for detailed recommendations.

CURRENT STATUS

EPA identified eight National Primary Drinking Water Regulations as candidates for revision at the 3rd 6-year review in January 2017. A few of the eight candidates are Chlorite, haloacetic acids (HAA), and Total Trihalomethanes (TTHMs). Potential revisions focus on improving and expanding DBP protection, such as revising MCL for HAA5, expanding focus to brominated HAAs through HAA6Br or HAA9, and revising precursor removal requirements. Additionally, EPA is also assessing information on unregulated DBPs, including chlorate and nitrosamines.

EPA determined that new information on health effects, treatment technologies, etc. require detailed analysis in the DBPR. Thus, the EPA is currently seeking public comments. No regulatory decision has been made regarding these contaminants. The schedule for the

draft and final rules are proposed to be out by July 2024 and September 30th, 2027, respectively.

Table 4.3: Initial Operational Evaluation Report Recommendation (eHT, 2015)

WTP Recommendations Implementation Status from City Initial Compliance Strategies

Both Utilization of sodium hydroxide to optimize pH Implemented

Both Addition of multiple ammonia application points Not Implemented

GR Relocation of ammonia application point Implemented

LP

Both

Developing disinfection credit for ozone, specifically at the end of disinfection zones D3 or D5 Implemented

Potential Compliance Strategies

Utilize enhanced coagulation for TOC Reduction

a) Reduce lime application OR

b) Use advanced coagulant

Implemented. Optimized coagulant dose and lowered lime dose

Both Evaluation of free chlorine contact zones Not Implemented

Both Post -Clearwell chloramine boost Not Implemented

GR Modification of clearwell piping Implemented

GR Addition of raw water oxidation capability Not Implemented

4.8 PER- AND POLYFLUOROALKYL SUBSTANCE (PFAS) BACKGROUND

PFAS are a group of synthetic chemicals utilized in various industries and consumer products since the 1940s. According to current scientific evidence, excessive amounts of some PFAS may cause adverse effects such as cardiovascular health issues. It endures in the environment and can bioaccumulate, or buildup, in the bodies of animals. However, studies are still being conducted to identify how varying levels of PFAS exposure can result in a range of health impacts. PFAS were included in UCMR 3. The most frequently detected PFAS were Perfluorooctane Sulfonic Acid (PFOS) and Perfluorooctanoic Acid (PFOA). In 2016, EPA established a formal Health Advisory Level (HAL) for these two compounds. Additionally, EPA developed a PFAS Action Plan in February 2019, which included specific goals related to additional research to regulate the contaminant.

Certain technologies have been discovered to remove PFAS from drinking water, particularly PFOA and PFOS, such as activated carbon adsorption, ion exchange resins, and high-pressure membranes.

CURRENT STATUS

The EPA declared that it is proposing to regulate PFOS and PFOA In February 2020 under the SDWA. The EPA has developed and provided four new draft documents to the Science Advisory Board (SAB) PFAS Review Panel for scientific review of these documents. The information from these documents would aid in updating the health advisory on PFOA and PFAS as well as setting the proposed PFAS National Primary Drinking Water Regulation for publication in Fall 2022. PFOA is a carcinogen; typically, MCLGs for carcinogens are set to “0”. Based on the revised approach for assessing the toxicity of PFOA and PFAS, lower toxicity values are proposed by EPA, as shown in Table 4.4.

While PFOA and PFOS are the most widely used and studied chemicals in the category, the EPA is seeking public input on draft toxicity assessments for GenX chemicals and perfluorobutane sulfonic acid (PFBS) to expand the public’s knowledge of other PFAS.

EPA will establish a National Primary Drinking Water Regulation for PFOS and PFOA if a positive regulatory determination is finalized. Refer to Appendix C for the strategic timelines for PFAS Roadmap. Additionally, 29 PFAS are included in UCMR 5 to analyze the occurrence and frequency of the contaminant in the nation’s drinking water system. Based on the draft UCMR, water systems will be asked to look for different sources of PFAS within their watershed in addition to monitoring.

4.9 CONCENTRATION-TIME (CT) STUDY FOR WATER TREATMENT PLANTS

The disinfection process in a WTP is evaluated in a CT study. The concentration (C) of a disinfectant and the theoretical contact time (T) of a disinfectant in each stage of treatment are the factors used to compute CT. Surface water monthly operating reports (SWMORs) for surface water systems are completed using the data obtained from the CT study. CT study helps to determine an effective contact time, number of disinfection zones required and verify the WTP’s compliance with disinfection requirements. CT studies are required for approval of a new WTP, WTP renovation, or to grant an exception request.

A disinfection zone is the section of the plant beginning at a disinfectant injection or monitoring point and finishing at the subsequent disinfectant injection or monitoring point. Golden Road WTP has three disinfection zones, D1, D2, D3A, and D3B. Disinfection is obtained through free chlorine in zone 1 and chloramines in the remaining zones. Golden Road WTP received an exception to the 0.5 NTU effluent turbidity rule in June 1993. Based on the submitted tracer study, the plant provided 16 minutes of T10 contact time in filters at the maximum rated capacity of 32 MGD.

PFOS 20 ng/kg-day 0.0079 ng/kg-day

Lake Palestine has eight disinfection zones, D1A, D1B, D2A, D2B, D3, D4, D5, D6, D7, D8. Disinfection is obtained through ozone in D1A to D5, free chlorine in zones D6, D7, and chloramines in D8. Based on the CT study conducted on April 24. 2012 for Lake Palestine,

Table 4.4: PFOA and PFOS Health Advisory

the primary disinfectant and CT credit is based on measured ozone residual within the ozone contactors, followed by free chlorine and/or chloramine use in later stages. However, based on the current site conditions, ozone cannot obtain disinfection with any regularity. The only way to consistently use ozone for disinfection credit is to perform a major upgrade to the system. Disinfection zone D6 includes rapid mix, flocculation, and sedimentation basin. Disinfection zone D7 encompasses filters and disinfection zone D8 includes clearwell inlet boxes, clear wells, and high-service pump station wet wells. Halff analyzed the surface water monthly operating report for Golden Road and Lake Palestine WTP from June 2021 to November 2021. The treatment plant’s performance on giardia

and virus inactivation was within the performance standards established by the CT study.

4.10 CONCLUSION

The City is authorized to treat raw water from Lake Palestine WTP and Golden Road WTP following the current regulatory requirements from EPA and TCEQ. WTP expansion and upgradation works must stay abreast of the new development in drinking water regulations because they will undoubtedly have a significant impact on the choice of design of other treatment processes. The following table summarizes the City’s compliance with the current regulation and potential regulations to be on City’s radar.

4.5: Summary of Drinking Water Regulations

City of Tyler compliance with the regulation Potential regulations/revisions to be on City’s radar

◦ Compliant based on the 2020 DWR

◦ LCRR compliance date: October 16th, 2024

◦ Trigger Level (10ppb)

◦ Monitoring, testing procedure, location, and frequency of regulatory updates

◦ Lead service line public inventory development and replacement plan

◦ New regulation: Lead and Copper Rule Improvements (LCRI). The final action date before October 16th, 2024

◦ Compliant based on 2020 DWR and repeated sampling results. TCEQ accepted the level 1 assessment conducted by City

◦ Compliant based on the 2020 DWR

◦ Draft and final revised rules to be released in July 2024 & September 2027

◦ The City has experienced intermittent periods of noncompliance with DBP regulations. Currently compliant with the DBPR rule since 2017

◦ Not yet regulated, so there is no compliance status to speak of yet.

◦ Potential revision to MCL for HAA5

◦ Focus on brominated HAAs and revised precursor removal requirements

◦ Draft and final revised rules to be released in July 2024 & September 2027

◦ Proposed PFAS DWR for publication in Fall 2022

◦ Monitor 29 PFAS in UCMR 5

◦ Water systems to look for different sources of PFAS within their watershed

Table

5 Water Treatment Plant Evaluation

Environmental legislation and regulation requirements are a significant consideration in selecting technology and designing the treatment process. The TCEQ has regulations on WTP design, operation, and maintenance requirements for PWS. To communicate these requirements, the TCEQ has published a set of rules and requirements compiled in 30 TAC, Chapter 290 Subchapter D. This chapter lists the minimum standards a public drinking water system must meet to comply with these rules. TCEQ conducts a comprehensive compliance investigation (CCI) of each community’s PWS every three years. The City is authorized to operate and maintain Lake Palestine WTP and Golden Road WTP following the TCEQ regulatory requirements. The capacities and characteristics of the treatment units were compared against the requirements established in the TCEQ. See Appendix D for a detailed evaluation.

5.1 TCEQ CRITERIA AND COMPLIANCE

Capacity: Any surface water treatment plant that provides or is being designed to provide

1. 7.5 MGD or more must be able to meet either the maximum daily demand or

2. the minimum required 0.6 gpm per connection, whichever is larger, with the largest filter offline.

Lake Palestine and Golden Road WTP design treatment capacity are 30 MGD and 28 MGD, respectively. The actual capacity at Golden Road WTP is 28 MGD, and the typical production rate is 22 MGD. With the largest filter offline, the WTP capacity exceeds the maximum daily demand.

Capacity: Surface water supplies must meet the following requirements:

1. a raw water pump capacity of 0.6 gpm per connection with the largest pump out of service

2. a treatment plant capacity of 0.6 gpm per connection under normal rated design flow

3. a covered clear well storage capacity at the treatment plant of 50 gallons per connection or, for

systems serving more than 250 connections, 5.0% of daily plant capacity

The total number of connections in the study area is 34,040. For an assumed peaking factor of 2.5 and 60/40 split between Lake Palestine and Golden Road WTP.

Lake Palestine WTP:

1. Required RW pump capacity: 12254.4 gpm, RWPS (1 stand-by) = 20833.2 gpm

2. Required treatment plant capacity = 17.6 MGD, Rated treatment plant capacity = 30 MGD

3. Required clear well storage capacity = 1.5 mg. Actual storage capacity of 1 tank = 1.99 mg (total two tanks)

a. As mentioned in section 2.2, the pumps use only the top 5 feet of clear well volume. As the clearwell storage is expected to double with the expansion of the Lake Palestine WTP, it’s essential for the utility to confirm each WTP has 1.5 mg available for use.

Golden Road WTP:

1. Required RW pump capacity: 8170 gpm, RWPS (1 stand-by) = 25,000 gpm

2. Required treatment plant capacity = 11.8 MGD, Rated treatment plant capacity = 28 MGD

3. Required clear well storage capacity = 1.2 MG. Actual storage capacity of 1 tank = 2 MG (total two tanks)

Flocculator: Plants with a design capacity greater than 3.0 MGD must provide at least two sets of flocculation equipment designed to operate in parallel. Public water systems with other surface water treatment plants, interconnections with other systems, or wells that can meet the system’s average daily demand are exempt from the requirement for redundant flocculation equipment.

Lake Palestine WTP: Design capacity of WTP = 30 MGD. Six flocculation units with three compartments in series.

Golden Road WTP: Design capacity of WTP = 28 MGD. There are four clariflocculators in Golden Road WTP. The flocculator motors in all four clarifiers operate at too high of an RPM to be run since they break up floc too much. Sufficient mixing occurs without the motors running.

Clarification: When operated at their design capacity, basins for straight-flow or up-flow sedimentation of coagulated waters shall provide either a theoretical detention time of at least six hours in the flocculation and sedimentation chambers or a maximum surface overflow rate of 0.6 gpm/sq ft of surface area in the sedimentation chamber.

Lake Palestine WTP:

Computed Detention Time = 3.4 hours (TCEQ minimum 6 hours)

Computed Overflow Rate = 0.56 gpm/sq ft (TCEQ maximum 0.6 gpm/sq ft)

Golden Road WTP:

Computed Detention Time = 3.3 hours (TCEQ minimum 6 hours)

The clarifloculator basin is divided into two, a flocculation chamber (inner) and a clarification zone (outer chamber).

Computed Overflow Rate (@ clarification zone) = 0.60 gpm/sq ft (TCEQ maximum 0.6 gpm/sq ft).

Filtration: Where high-rate gravity filters are used, the design capacity shall not exceed a maximum filtration rate of 5.0 gpm/sq ft. At the beginning of filter runs for declining rate filters, a maximum filtration rate of 6.5 gpm/sq ft is allowed.

Lake Palestine WTP: Assuming 1/8 filters out of service, Filtration Rate = 4.96 gpm/sq ft (TCEQ maximum 5.0 gpm/sq ft)

Golden Road WTP: Assuming 2/16 filters out of service, Filtration Rate = 3.19 gpm/sq ft (TCEQ maximum 5.0 gpm/sq ft)

Meets TCEQ criteria of high-rate gravity filter. This criteria needs to be re-evaluated if the number of filters out of service at a time is different from the assumptions.

Filtering Material:

1. The depth of filter sand, anthracite, granular activated carbon, or other filtering materials shall be 24 inches or greater and

2. Provide an L/d ratio, as defined in §290.38 of this title (relating to Definitions), of at least 1,000.

Lake Palestine WTP:

1. Depth of filter material: 12-inch Sand, 24-inch Anthracite, which meets the minimum depth specified by TCEQ.

2. The L/D ratio computed based on the assumed size of the filter particle is 1355, which meets the TCEQ minimum criteria of 1000.

Golden Road WTP:

1. Depth of filter material: 12-inch Sand, 24-inch Anthracite, which meets the minimum depth specified by TCEQ.

2. The L/D ratio computed based on the assumed size of the filter particle is 1219, which meets the TCEQ minimum criteria of 1000.

Backwash: The rate of flow of backwash water shall not be less than 20 inches vertical rise per minute (12.5 gpm/sq ft) and usually not more than 35 inches vertical rise per minute (21.8 gpm/sq ft).

The rate of backwash at both WTP is 20 gpm/sq ft.

Storage: Except as provided in this clause, adequate containment facilities shall be provided for all liquid chemical storage tanks.

Containment facilities for a single container or multiple interconnected containers must be large enough to hold the maximum amount of chemicals that can be stored with a minimum freeboard of six vertical inches or to hold 110% of the total volume of the container(s), whichever is less.

Common containment for multiple containers that are not interconnected must be large enough to hold the volume of the largest container with a minimum freeboard of six vertical inches or to hold 110% of the total volume of the container(s), whichever is less.

No containment facilities are required for hypochlorite solution containers with 55 gallons or less capacity.

Lake Palestine WTP:

Assuming that Lime, Ammonia, and Chlorine storage tanks in Lake Palestine WTP are double contained similar to Golden Road WTP.

Volume of alum bulk tanks #1 and #2 = 12,000 gallons, Volume of alum containment = 18,949 gallons

Volume of alum day tank = 1,450 gallons, Volume of alum containment = 498 gallons.

Volume of new fluoride bulk storage tank = 5400 gallons, Volume of fluoride containment = 10,240 gallons

Volume of fluoride day tank = 250 gallons, Volume of fluoride containment = 592 gallons

Volume of old fluoride bulk storage tank = 6,000 gallons, Volume of fluoride containment = 7,659 gallons

Golden Road WTP:

Fluoride, Lime, Alum, and Ammonia storage tank are double contained

Volume of alum day tank = 500 gallons, Volume of alum containment = 2,007 gallons

Volume of fluoride day tank = 300 gallons, Volume of

fluoride containment = 1,316 gallons

Volume of caustic day tank = 540 gallons, Volume of caustic containment = 1,245 gallons

Volume of caustic bulk tank = 8,700 gallons, Volume of caustic containment = 26,906 gallons

The above section lists only the key criteria applicable to a water treatment plant. See Appendix D for detailed information on the TCEQ regulations and its compliance with Lake Palestine and Golden Road WTP.

5.2 INDUSTRY STANDARDS AND COMPLIANCE

In the absence of TCEQ criteria to evaluate the existing ozone contactor basin in Lake Palestine WTP, industry standards as listed below are used.

Ozone Contactor: The type and shape of ozone contactors affect calculations for Giardia and Virus inactivation credits. Bubble diffuser contactors for disinfection applications typically have 6, 8, 10, and 12 chambers. Few chambers with shorter detention times (6 to 10 minutes) are commonly used to meet Giardia and virus disinfection objectives since the required CT values are relatively low. Extra chambers and detention time (20-60 minutes) are used for enhanced disinfection applications (Cryptosporidium).

5.3 DISCUSSION

The major treatment units in Lake Palestine WTP comply with the TCEQ Chapter 290 requirements. The treatment plant’s capacity, raw water pumps, and clear well tanks are sufficient to meet the daily demands. The design parameters evaluated for the units, such as mixing, flocculation, sedimentation, clarification, and filtration, were compliant with the TCEQ requirements. The facilities out of full compliance with the requirements of TAC 30 Chapter 290 are listed in Table 5.1. Per the TCEQ requirement, the volume of the containment structure should be at least 110% of the volume of the container. The containment for the Alum Storage Tank # 3 housed inside the Alum Storage Handling Building is inadequate. Raising the walls by an additional 1.5 feet could achieve the required containment volume per TCEQ.

The major treatment units in Golden Road WTP comply with the TCEQ Chapter 290 requirements. The rated capacity of the treatment plant, raw water pumps, and clear well tanks are sufficient to meet the daily demands. This permitted treatment capacity is 28 MGD. The issues in Golden Road WTP are mainly a result of the aging infrastructure. During the discussion with the plant operator, it was noted that the underground piping and flocculation motors are in poor shape. The WTP operators could not get spare parts for mechanical equipment such as chlorinators, ammonia tanks, and chlorine tank meters as these have become obsolete.

These treatment plants will remain grandfathered from Chapter 290 regulations until significant changes occur to the treatment process. At that point, the plant must conform to the governing regulations at the time of the change. In general, like-for-like equipment replacement does not qualify as a significant change.

6. Geosmin in WTP

The presence and treatment of geosmin and other algae is a significant challenge at Lake Palestine WTP. These compounds impart earthy, musty tastes at low concentrations of 5-10 ng/L. Concentrations of geosmin at Lake Palestine WTP vary depending on the time of year, with peaks generally occurring from December to March. The geosmin concentration in the raw water from Lake Palestine ranges from 3.3 to 1330 ng/L for a period between 2013 to 2022. The geosmin concentration in Lake Palestine WTP is considered to be in the high to very high range compared to other WTPs across the country, such as Central Lake County Joint Action Water Association plant, Illinois (43 ng/L), Shenango WTP, Pennsylvania (159 ng/L), Manatee County WTP, Florida (138 ng/L), Anderson WTP, South Carolina (300 to 700 ng/L), East Bay Municipal Utility District, California (400 to 500 ng/L), City of Tampa, Florida (900 ng/L), City of Wichita Falls, Texas (maximum 1050 ng/L),

Powdered Activated Carbon (PAC) and an ozone unit are currently employed in Lake Palestine WTP to treat geosmin. The dosage of PAC and ozone are regulated based on the influent geosmin concentration. However, these treatment techniques are currently inadequate

to deal with the high geosmin concentration, especially during the peak season. This chapter presents options to tackle high geosmin concentration in Lake Palestine WTP and the recommended solution. The initial sections present an overview of the sources, health effects, and treatment techniques for compact geosmin based on recent research papers. The subsequent sections discuss the current geosmin levels and treatment techniques adopted in Lake Palestine WTP. The end of this chapter outlines the recommended course of action to handle geosmin at LP WTP.

6.1 SOURCES

The presence of undesirable taste-and-odor (T&O) chemicals in surface water supplies is a problem affecting drinking water utilities all around the country. Certain species of naturally-occurring Cyanobacteria, also known as blue-green algae, produce compounds commonly found in water. Among these are geosmin, 2-methylisoborneol (MIB), and cyanotoxins. Geosmin and MIB produce earthy and musty scents, respectively, prompting taste and odor issues with drinking water. See Appendix E Part 6.1 for extended explanations about geosmin, MIB, and cyanotoxins.

Aphanizomenon Microcystin, Anatoxin-a, and Cylindrospermopsin

Psuedoanabeana Microcystin, Anatoxin-a MIB and Geosmin

Cylindrospermopsis Cylindrospermopsin Anecdotal-MIB

(Source: AWWA, WRF (2016), “Managing Cyanotoxins in Drinking Water”)

Table 6.1: Geosmin Producing Cyanobacteria

6.2 HEALTH EFFECTS

Geosmin and MIB are not harmful but impart vaguely moldy tastes at very low concentrations. Geosmin and MIB are generally detectable at a low concentration of 5-10ng/L. While currently unregulated because they have not been linked to any adverse health impacts, the impacts on taste and odor affect the perceived safety of tap water. The presence of T&O issues in drinking water may lead to a loss of consumer trust and, as a result, a reduction in water consumption, leading to a shift to other drinking water sources. Other cyanotoxins that frequently co-occur with these compounds have adverse health effects ranging from a mild skin rash to severe illness or, in rare circumstances, death. For example, Anatoxins detected in Lake Palestine fall under the category of chemicals known as neurotoxins. However, no information is available on the carcinogenicity of anatoxin-a in humans or animals or potential carcinogenic precursor

effects. The EPA has released an algal toxins health advisory for cyanotoxins, cylindrospermopsin, and microcystins. Refer to Section 4.6 for more information on the health advisory. It is crucial to monitor cyanotoxins and ensure that the cyanotoxins levels are below the threshold during a T&O outbreak. See Appendix E, part 6.2, for extended explanations of health effects.

6.3 TREATMENT TECHNIQUES AND CURRENT PRACTICES

The fundamental issue with MIB/geosmin is their extremely low odor threshold concentrations and their resistance to removal in traditional water treatment methods such as coagulation, sedimentation, filtration, and chlorination (Bruce et al., 2002). Table 6.2 summarizes various water treatment techniques to reduce or eliminate geosmin and MIB in drinking water.

Non-Oxidative Methods

Powdered Activated Carbon (PAC)

Biological Techniques

Common Oxidants (Chlorine, chloramines, potassium permanganate)

Algaecide Treatments to Source Water

The most commonly adopted technology for MIB/geosmin removal and typically used to remove the medium concentration of MIB/geosmin. Effective for cyanotoxins such as microcystins and cylindrospermopsin.

Combining biological methods with other T&O treatment techniques to improve MIB/geosmin removal has become increasingly popular. Effective in removing low to medium concentrations of MIB/geosmin.

Oxidative Methods

Chlorine, chloramines, and potassium permanganate are ineffective in MIB/geosmin removal (Glaze et al., 1990; Lalezary et al., 1986). Chlorination is effective for oxidizing extracellular cyanotoxins (other than anatoxin-a) when the pH is below 8.

Copper-based products have been adopted in the past to compact T&O issues. Temporary solutions cause a public reaction and environmental concerns. In some situations, the application of algaecides leads to the lysis of cyanobacteria and the release of additional cyanotoxins. The EPA does not encourage using algaecides in drinking water sources (EPA, 2015).

Ultraviolet (UV) Radiation UV irradiation dosages required for MIB or geosmin oxidation are approximately 100 times greater than dosages used for microbial inactivation. UV degrades cyanotoxins when used at high doses but is inadequate to destroy cyanotoxins at doses used for disinfection. UV radiation alone is not typically used to treat geosmin and MIB.

Ozone

Advanced Oxidation Process(Ozone at high pH, Ozone + hydrogen peroxide, ferrous ion+ hydrogen peroxide, UV + hydrogen peroxide)

Ozonation is effective in reducing or eliminating T&O complaints. Effective in removing medium to high concentrations of MIB/geosmin. Very effective for oxidizing extracellular microcystin, anatoxin-a, and cylindrospermopsin.

In AOP, the oxidation of organic contaminants occurs primarily through reactions with hydroxyl radicals. Effective at treating extracellular microcystins, cylindrospermopsin, and anatoxin-a. Effective in removing medium to very high concentrations of MIB/geosmin.

Table 6.2: Geosmin and MIB treatment practices and their relative effectiveness

The following section discusses the treatment mechanism, dosage, factors influencing the treatment effectiveness, advantages, and limitation of selected treatment techniques.

A. PAC:

PAC is porous, like a solid sponge, with a large surface area to which contaminants can adhere. PAC has a highly porous structure with varying ranges of pore sizes. Intermolecular attractions in the smallest pores create adsorption forces. These forces cause

dissolved contaminants such as MIB and geosmin to be condensed and precipitated from the solution into the molecular scale pores. PAC with the adsorbed contaminants is removed from the water during the coagulation and filtration process.

The factors affecting geosmin/MIB removal efficiency using PAC are illustrated in Table 6.3. Refer to Appendix E Part 6.3 Section A for detailed information regarding the factors.

Table 6.3: Factors affecting Geosmin Removal using PAC

Contact time between PAC and organics in source water is important and depends on the ability of the carbon to remain in suspension as a particle or in floc. The amount of removal during the sedimentation process is considerably less since PAC is removed within the first 25% of the length of the sedimentation basins. Based upon suspended solids analysis, PAC contact time is defined as the hydraulic retention time (HRT) in the pre-sedimentation and flocculation basins. Therefore, maximizing the contact time and sufficient mixing between PAC and raw water before the sedimentation process is critical. For removing taste and odor compounds, a minimum contact time of 15 min is sufficient. However, prolonged contact times are required for MIB and geosmin removal (AWWA 1969). The process of adsorption of MIB and geosmin by PAC takes time (> 1 hour) (ASU, 2002).

The location of the PAC application point should be in conjunction with the treatment plant’s design and operation. Application of PAC at the earliest point, such

as intake and source water pipeline, can increase the contact time. However, PAC may absorb substances that would otherwise be removed by coagulation, increasing PAC dose. On the contrary, PAC addition at a later stage may require higher doses to account for shorter contact time and interference by other chemicals, such as coagulants and chlorine. Refer to Table E.1 in Appendix E Part 6.3 Section A for additional information on various PAC application points.

PAC is fed either as powder using dry-fed equipment or slurry using metering pumps. The slurry form is preferable if the feed is continuous and maximum feed rate is greater than 100 pounds/hour. However, if not, continuously dosed continuous stirring is required to keep carbon in suspension. PAC is the most commonly used treatment technique for removing seasonal T&O in water. Key findings from recent studies on PAC in treating geosmin and MIB are summarized in Table E.2 in Appendix E Part 6.3 Section A.

B. BIOLOGICAL TREATMENT :

Biological treatment for eliminating T&O in water and wastewater has become increasingly popular in recent years. Biological approaches have a limited application in drinking water and are primarily employed with filtration or biofiltration. Biofiltration techniques, such as slow sand filtration and GAC rapid filtration, help grow contaminant-degrading bacteria. Several researchers have also looked into combining biological methods with other T& O treatment techniques to improve MIB/geosmin removal in water. The combination of approaches could be employed as a polishing phase or to remove the contaminants to the desired level. Two biological treatment techniques implemented to remove geosmin and MIB are described below. Refer to Table E.3 in Appendix E Part 6.3 Section B for key findings from recent studies on biological treatment.

Ozone+Biofiltration:

Ozone removes part of geosmin and MIB and generates more biodegradable byproducts. Following ozonation, biofiltration dramatically reduces the concentration of these highly degradable ozonation byproducts. Thus, augmented with upstream ozonation, biofiltration oxidizes MIB and geosmin and generates biodegradable organic matter to stimulate microbial degradation during downstream biofiltration.

Biological Pretreatment:

In this technique, biofilters preceded the conventional treatment train to take advantage of the biodegradable organic carbon and nutrients that would otherwise be removed through conventional treatment.

Although integrated technologies involving biofiltration have shown success in removing MIB/geosmin, the efficiency of these techniques is highly dependent on biodegradable organic matter (BOM) characteristics, concentrations in the influent of biofilters, the transient nature of odor events, seasonal water temperature variations, filter media, empty bed contact time, and hydraulic loading rate. In addition to the filter unit, implementing this technology would require upgrading the existing backwash facility, such as the pumping system, air scour system, etc. This technique is sufficient for treating moderate MIB and geosmin concentrations less than 50ng/L.

C. ULTRAVIOLET (UV) RADIATION

UV photolysis is a photochemical reaction where a contaminant absorbs UV light, and the photons break down the chemical bonds of the element and reduce the chemical to its elemental components. UV acts to inactivate microorganisms as well as break down contaminants simultaneously. This is accomplished without the formation of by-products such as THMs or bromate. UV degrades cyanotoxins when used at high doses but is inadequate to destroy cyanotoxins at doses used for disinfection, per the AWWA (Sept 2016). For example, the UV inactivation dose for Cryptosporidium is about 40 mJ/cm2, while the photolytic destruction dose for microcystin, cylindrospermopsin, anatoxina, and saxitoxin ranges between 1,530 to 20,000 mJ/cm2 (EPA, 2019). Based on the study conducted by Arizona State University (2002), UV irradiation dosages required for MIB or geosmin oxidation are approximately 100 times greater than dosages used for microbial inactivation. The effectiveness of this technique is highly dependent on the organic content of the water. Therefore, UV irradiation probably is not cost-effective. UV radiation alone is ineffective at oxidizing microcystins and cylindrospermopsin at doses typically used in drinking water treatment. However, UV has been used along with a catalyst (e.g., ozone, hydrogen peroxide, or titanium dioxide) to oxidatively decompose the cyanotoxins, especially anatoxin-a, cylindrospermopsin, and with high UV doses, microcystins (www.epa.gov).

D. OZONE

The EPA has approved ozone as a drinking water treatment method. Ozone is increasingly used in the United States to comply with DBPR and to inactivate Cryptosporidium. It has greater disinfection effectiveness against bacteria and viruses compared to chlorination. Ozone is usually fed at the beginning of the treatment plant (pre-ozonation), after sedimentation before filtration (intermediate ozonation), or at both locations. Achieving disinfection with ozone requires that the oxidation demand for ozone be satisfied first. This is necessary to develop an ozone residual concentration that can be used to calculate the CT value. The CT value is then used to confirm that the required amount of disinfection has been achieved. Thus, all rapidly reacting organic and inorganic constituents will be oxidized before disinfection can be confirmed.

Ozone is more soluble in water than oxygen, and ozone residuals last longer at low pH and in highly buffered waters. For design purposes, the decay rate constant in the pseudo-first-order kinetics equation for ozone-based decomposition must be determined for the water to be treated under expected operation conditions, including temperature, pH, and water quality. Ozone systems typically consist of four basic subsystems: ozone generation, feed gas preparation, contacting, and off-gas disposal. Ozone reaction times are moderately fast, with contact times of several minutes.

Ozone is generated by electrical discharge in an oxygen-containing gas. The introduction of ozone leads to the effective degradation of harmful pollutants present in water without forming harmful chlorinated byproducts. Ozone is a cost-effective and environmentally responsible alternative to oxidation with chlorine, absorption (activated carbon), or separation processes (reverse osmosis). Organic molecules react with ozone and are converted into structurally simpler organic molecules that can be more easily biodegraded.

Many taste and odor compounds, including geosmin and MIB, have been found to be effectively treated by ozone. Refer to Appendix E Part 6.3 Section C for key findings from studies on treating geosmin/MIB using ozone.

In general, ozone is considered a highly effective barrier for cyanotoxins in drinking water treatment. Ozone can be used to oxidize anatoxin-a (pH 7 to 10) and cylindrospermopsin (EPA, 2019). Bromate is a DBP that can form when ozone is used to treat water containing bromide. Per TCEQ requirements, all community public water systems that use ozone must monitor for bromate. The SDWA sets Maximum Residual Disinfectant Levels for bromate at 0.01 mg/L. The bromate level detected in the City on May 2022 was 0.005 mg/L.

E. ADVANCED OXIDATION PROCESS

AOP is a combination process that utilizes strong oxidants such as ozone, UV, and hydrogen peroxide to produce hydroxyl radicals. Compared to other oxidants, hydroxyl radicals have considerably higher oxidation potential, as shown in Table 6.4. When formed in water, it immediately degrades all existing oxidizable substances. The quick reaction kinetics and high degradation performance of AOP help eliminate numerous contaminants. The term AOP refers specifically to processes in which oxidation of organic contaminants occurs primarily through reactions with hydroxyl radicals. AOPs usually refer to a specific subset of processes that involve ozone, hydrogen peroxide, and/or UV light which are powerful treatment technologies by itself. The key to choosing the best AOP solution is to find the right combination of these processes to produce the most efficient hydroxyl radicals that reduce the contaminants. AOP treatment technology has been extensively used in WTP experiencing T&O issues. The additional benefits of AOP is illustrated in Figure 6.1. More information about AOP and its mechanisms can be found in Appendix E Part 6.3 Sections D, E, F, and G.

Table 6.4: Relative oxidizing power of chemicals

(Source: Metcalf and Eddy, 2003)

Figure 6.1: Contaminants Removed by UV, Ozone, and AOP Process

6.4 CASE STUDIES ANDERSON WTP

Anderson Regional Joint Water System (ARJWS) is a wholesale drinking water provider that pumps up to 48 MGD 200,000 customers in Upstate South Carolina. The source water is collected from Lake Hartwell. The cyanobacteria that spread across Lake Hartwell in the summer of 2013 produced non-toxic compounds geosmin and MIB, the sources of the “dirty” tasting water. The plant’s concentration in the summer of 2014 was in the 300 to 700 ng/L range. Although ARJWS adopted algaecide treatment to source water and PAC addition within the treatment plant to absorb T&O compounds, desired results were not observed. A major WTP upgrade was initiated in 2015 to resolve issues such as taste, odor, color, iron and manganese, and emerging contaminants.

Four treatment options were analyzed: ozone, ozone + hydrogen peroxide, UV + hydrogen peroxide, and ozone + hydrogen peroxide + UV. Bench-scale testing was performed to determine parameters such as contact time, chemical dose, equipment headloss, equipment dimensions, energy requirements, and capital and operational costs. Four rounds of testing at varying oxidant doses and MIB concentrations revealed that all technologies were effective at treating MIB from an influent concentration of 400 ng/L to 4 ng/L at an ozone concentration of 4 mg/L.

Results of the study indicated that ozone alone would be sufficient for most operating conditions and had the lowest lifecycle cost for a 20-year evaluation. However, a detailed analysis of augmenting ozone with hydrogen peroxide showed that the lifecycle cost would increase slightly, but capital expenditure would be reduced using a smaller ozone contactor basin.

Life cycle costs were computed for an average flow rate of 20 MGD as shown in Figure 6.4. Feeding ozone alone was the least costly over the 20 years at an estimated capital cost of $12.5 million and an annual O&M cost of $378,000.

Figure 6.2: Process Life Cycle Cost Estimate using Present Value at 20

Ozone + hydrogen peroxide AOP was the most feasible overall option, providing operational flexibility and an additional AOP barrier when needed. The ozone + hydrogen peroxide treatment process implemented in ARJWS can feed ozone alone and augment with hydrogen peroxide for quenching ozone residuals and treating maximum influent levels.

EAST BAY MUNICIPAL UTILITY DISTRICT

East Bay Municipal Utility District (EBMUD) is a public utility district that provides drinking water for 1.4 million customers in the eastern side of San Francisco Bay. Sorbrante and Upper San Leandro WTPs (maximum design flowrate 60 MGD) under EBMUD have ozone+hydrogen peroxide AOP unit to compact taste and odor issues. The original ozone system installed in 1991 has three 750 lb/day air-fed ozone systems with an ozone concentration of 2.2% and a maximum dose of 3 mg/L. The ozone is diffused into settled water (intermediate) ozone contactor with 11 min HRT for maximum flow. The geosmin concentration entering the plant in the summer of 2015 was 400 to 500 ng/L. To reduce the O&M cost and handle the WTP’s increased taste and odor issues, the following installations and upgrades were performed in 2017.

• Installation of three 1750 lb/day high-efficiency oxygen-fed generators. Closed loop cooling water, nitrogen system.

• Installation of 20,000-gallon liquid oxygen (LOX) facility, 6,000-gallon hydrogen peroxide facility

MGD in ARJWS

(Source: Xylem (2019))

with secondary containment, five metering pumps, double-contained high-density polyethylene (HDPE) buried piping

• Buried/Encased ozone piping

• Installation of ozone destruct unit

• Ozone contactor basin repair and a new diffuser

• Modification to ozone generator building such as new fire separation walls, motor control centers (MCC), heating, ventilation, and air conditioning, fire alarm, sprinkler system, and emergency generators

• Installation of potassium permanganate system

• Refurbished MCCs and switchgear

The new unit could achieve maximum production of 3500 ppd, 7.0 mg/L at 60 MGD @ 10%. The total construction cost for this project was $47.9 million, of which $5.5 million was the cost of ozone equipment.

One of the lessons learned from his project was to plan for operation without ozone (using PAC).

6.5 GEOSMIN AT LAKE PALESTINE WTP

Concentrations of Geosmin and MIB at Lake Palestine vary depending on the time of year. Figures 6.3 and 6.4 below show that Geosmin levels typically increase from December to March. The cool temperature and low light could be the factors simulating the geosmin production in this season. It is generally observed that spikes in MIB and Geosmin concentrations do not co-occur. Spikes in MIB concentrations are typically observed from July to October. The City provided Halff with the raw and treated water geosmin and MIB concentration from November 5, 2013, to February 28, 2022. The average raw and treated water geosmin for this period is 142.8 ng/L and 14 ng/L, respectively. The average raw and treated water MIB for this period are 7.3 ng/L and 3.7 ng/L, respectively.

Figure 6.3: Raw and Treated Geosmin at Lake Palestine WTP

Figure 6.4: Raw and Treated MIB at Lake Palestine WTP

From Table 6.4, it is noted that the average concentration of geosmin (values greater than 300) for a period between 2013 to 2022 is 511.1 ng/L. The maximum geosmin and MIB concentrations vary between 3.6 to 1330 ng/L and 0 to 118 ng/L,

respectively. As shown in Table 6.5, the MIB concentration in raw water is 25 times lesser compared to geosmin. This could be related to the cyanobacteria genus present in the raw water.

Figure 6.5 shows the frequency of extreme geosmin and MIB events from 2014. Figure 6.6 shows the percentage of geosmin removal across an eight-year period. The average percentage removal of geosmin and MIB from November 5, 2013 to February 28, 2022

is 85% and 30%, respectively. The results indicate the need to adopt a treatment technique capable of dealing with increased geosmin loads with high removal efficiency.

Figure 6.5: Frequency of Geosmin and MIB Events

Figure 6.6: Percentage of Geosmin Removal

Table 6.5 Raw-water Geosmin Levels in Lake Palestine WTP during Peak Geosmin Season

1. Data available from 5th November 2013 to 28th February 2022

2. Average value during peak geosmin season 2013 is computed with data from 2013 December to 2014 March (typical for all years except otherwise noted)

3. Average value during peak geosmin season 2022 is computed with data from 2021 December to 2022 February due to the unavailability of data

4. Number of data points available within each year is different

Table 6.6: Raw-water MIB Levels in Lake Palestine WTP during Peak Geosmin Season

Remark:

1. Data available from November 5, 2013 to February 28, 2022

2. Number of data points available within each years is different

6.6 CURRENT TREATMENT TECHNIQUES AT LAKE PALESTINE WTP

PAC and Ozone are used in Lake Palestine to treat geosmin. However the current treatment techniques fail to limit the geosmin levels to below the detectable threshold of 5 ng/L, especially during peak geosmin periods. The T&O complaints in the City are generally due to a) a spike in geosmin to a level beyond the treatment capability of the unit, b) failure of the T&O treatment units. Table 6.6 outlines the T&O events and complaints.

Table 6.7: T&O Events and Complaints in Lake Palestine WTP

Jan 20, 2022

Ozone treatment system is offline due to a failure with the main control panel.

Mar 1, 2021 Spike in Geosmin Levels

Jan 8, 2020

Golden Road WTP offline. Lake Palestine

WTP is the sole provider of treated water.

Removal of geosmin 93%

PDOevoPLUS ozone system, built in 2003. As shown in Figure 6.12, the ozone system in Lake Palestine has four basic subsystems: feed gas supply, ozone generator (ozone vessel + power supply unit), ozone contactor, and off-gas ozone destruct. There are two 2000 kW conventional horizontal tube-type ozone generators housed inside the ozone building in Lake Palestine WTP.

Feb 4, 2019

Golden Road WTP offline. Lake Palestine

WTP is the sole provider of treated water.

Removal of geosmin 93%

OZONE UNIT IN LAKE PALESTINE

WTP

Lake Palestine WTP has a Xylem’s Wedeco

The feed gas preparation system supplies gas to the ozone generators in appropriate quantity and quality. In Lake Palestine, purchased LOX is delivered to the site and stored in two 11,000-gallon tanks. The original project in 2014 was designed for a plant flow rate of 20 MGD (25 MGD maximum). The ozone generator was designed for 550 PPD @ 12% capacity. 650 PPD @ 10%. The cooling water temperature is 70F. The typical ozone dosage is 2-3.5 mg/L and can go up to 6mg/L during peak geosmin season. The performance of the current generator is acceptable to excellent outside of worst-case events. However, during extremely high “peak” geosmin events, the generator cannot provide enough reduction of extremely high organic loading / high geosmin levels, and it causes it to run near max amperage. Currently, all settings changes are made manually. The City is aware that the ozone generator is nearing its end of life. However, based on the current and past performance, the City expects up to ten additional years from the system.

Figure 6.7: Flowchart of Ozone Unit in Lake Palestine WTP

Raw water enters the two parallel ozone contactors through a 48-inch diameter DI pipeline, and the flow to each contactor basin is controlled by a 48-inch butterfly valve. The basin has two parallel compartments, and ozone gas is applied to the raw water as it flows through the contact basin. The stored LOX is vaporized and conveyed to the ozone generator. The generated ozone gas is applied to the raw water as it flows through the contact basin. The ozone contact basins promote contact between the ozone gas to the raw water and retain the ozonated liquid for the required contact time. The conventional fine bubble diffuser contactor, consisting of over/under baffles, is used in Lake Palestine WTP. Following dissolution, the ozonated water continues through the contactor for oxidation and disinfection reactions. Ozone piping to each contactor includes a flowmeter/indicator/ transmitter and motorized control valve. These devices control gas flow rate and overall ozone treatment performance. Typically, the water depth over the diffusers is the most critical factor, increasing efficiency with increasing depth. Additional design parameters are outlined in Table 6.7. The ozone generator and diffuser grid system in Lake Palestine WTP is designed for a minimum 95% transfer efficiency. The ozone diffusers were last replaced in 2012 and have an efficiency of 98%.

ozone and an 8-hour OSHA standard of 0.1 ppm. Thus, the Lake Palestine ozone system uses a catalytic destruct unit for off-gas treatment. This technique passes the gas across a surface that catalyzes ozone decomposition to elemental oxygen.

PAC Unit in Lake Palestine WTP

PAC is dosed in the open channel before the rapid mix to control geosmin-related T&O events in Lake Palestine WTP year-round. The carbon dosage demand changes throughout the year and depends on geosmin concentration and the type and concentration of organic matter. The average raw and treated water TOC in Lake Palestine WTP is 5.99 and 2.73, respectively. PAC is fed at a lower dose during the offseason (April to November). The typical PAC dosage range is 5 mg/l to 42 mg/l.

PAC comes in super bags and is placed on the carrier platform with the help of a hoist. A PAC feed operation creates carbon dust and physical strain on workers. When the bag outlet connection is released, PAC is fed into the hopper and discharged into the funnel.

6.9: Industry Standards on PAC

Contact Time for geosmin removal= >1 hr

(Note: The surface of PAC particles should not be coated with coagulants or other or other water treatment chemicals before PAC has adequate contact time with the source water)

T = 9.4 min

Dosing Point - Depends on the application Open channel before rapid mix basin. (Alum is dosed in rapid mix chamber)

Dose - Depends on design flow rate and geosmin levels, typically 15 mg/L -60mg/L

Ozone contactors with an efficiency of 90 to 100% have air exiting from the contactor with ozone concentration as high as 0.5% by volume. Although no regulations have been established on the level of ozone discharge into the atmosphere, this compares to 0.05 ppm of

5 mg/l – 42 mg/l

The remaining PAC in the super bag has to be continuously monitored. The dosing system, as shown in Figure 6.8, is used to discharge the funnel and feed the feed line. The injection of PAC into the feed line is regulated with the help of a weighing device. PAC feed rate is adjusted monthly based on the calculation tied to geosmin sampling of raw water feed. The feed

Table 6.8: Industry Standards on Ozone Systems

Table

system is manually operated and labor-intensive. In peak geosmin season, December through March, geosmin is tested for weekly or twice a week during concentrations above 700 ng/L. In non-peak seasons geosmin sampling is conducted bi-weekly; it takes $2,400 to test each sample. Currently, there is a high O&M cost associated with PAC. The recommended PAC industry standard and its compliance in Lake Tyler WTP are outlined in Table 6.8.

The dosage of ozone and PAC are determined based on these monitored results and a 50/50 treatment efficiency between the two units.

6.7 OPTIONS TO TACKLE GEOSMIN IN LAKE PALESTINE WTP

The central theme of the proposed T&O management strategy is the concept of multiple barriers. This concept widely used for pathogens (commonly known as the “swiss cheese method”) is applied to presenting options to tackle T&O issues. Out of the multiple control measures evaluated, several measures emerged as key elements of the taste and odor strategy. In many cases, it may not be possible to prevent the production of T&O compounds upstream, but water resources managers can manage the water supply system to prevent poor-tasting water from reaching consumers. This can be done by blending source waters, source switching, or in-plant treatment. These management techniques are discussed in the following section. Some T&O episodes may be prevented. For example, algaecides application in can reservoirs can be used to prevent the growth of T&O culprit algae. However, this option would require a detailed study, such as source identification, hydrological and environmental impact assessment. Results from the previous studies indicate this as a viable permanent option to tackle T&O issues.

The following options were evaluated to reduce/ eliminate geosmin’s presence in Lake Palestine’s drinking water.

• Source switching during high geosmin episodes

• Modification to raw water intake levels

• Lake Palestine and Lake Tyler water blending

• Modification of existing treatment techniques

SOURCE SWITCHING DURING HIGH GEOSMIN EPISODES

PAC and Ozone Dosage

There is no set dosage that ozone is fed. It can range from 1.6 mg/l to a max of 6.0 mg/l. A typical range is 2.0 - 3.5 mg/L. Lake Palestine WTP’s ozone dosage depends on the time of year and raw geosmin levels. During peak geosmin season (December to March), geosmin is sampled at the pump station and the plant at least weekly.

Poor-quality water can sometimes be avoided by switching production from a plant receiving poor-quality water to another that receives better-tasting water. For example, taking the Lake Palestine WTP offline during high geosmin episodes and shifting production to the Golden Road WTP could avoid the problem of high geosmin from Lake Palestine.

The key factor that must be considered in source switching is the total production capacity of the

Figure 6.8: PAC Unit in Lake Palestine WTP

operable WTPs and the total consumer demand. To some extent, total operational production capacity can be managed by conducting repairs at times other than the peak of the T&O season, so operational capacity is at a maximum when source switching is needed. In Lake Palestine WTP, peak T&O issues are in winter, when the water demand is the lowest. However, this maneuvering is more theoretical than practical in application. In reality there are many different major end of year maintenance items to schedule that make source switching even more difficult to achieve.

This option would require constructing a new raw water pipeline from Lake Tyler to Lake Palestine WTP. Appendix E part 6.6 shows this option’s proposed raw water pipeline route. This pipeline route minimizes

easement requirements by paralleling existing raw water line easement and ROW. The proposed route limits cutting across urban centers. Cost information for each project was calculated in 2022 dollars. The assumptions for the planning level costs are outlined in Appendix E Part 6.4. They are based on the uniform costing model (UCM) for the Regional Water Planning by Texas Water Development Board (TWDB), inputs from the manufacturer, and the engineer’s experience on previous projects. Table 6.9 summarizes the project’s total and annual costs, which have increased by 17% from the 2019 TWDB spreadsheet amounts to the equivalent of 2022 dollars. The total cost includes the cost of facilities and associated project costs. Refer to Appendix E Part 6.5 for a detailed cost estimate reflected in 2019 dollars.

Table 6.10: EOPCC for Proposed Raw Water Line from Lake Tyler to Lake Palestine WTP (2022 dollars)

Figure 6.9 shows the percent of the total flow into the system among various sources such as groundwater, Lake Palestine WTP, and Golden Road WTP. The figure illustrates that 100% contribution from Golden Road WTP is limited post-2014. This could be due to increasing demand and aging infrastructure in Golden Road WTP limiting its rated capacity. Thus, shifting production to Golden Road WTP during peak geosmin seasons, from December to March, was not considered

a permanent solution to tackle geosmin issues unless major upgradation works were conducted in this plant.

Thus, making this option feasible would require huge capital investment, including nearly $156,000,000 for the proposed raw water pipeline alone. Moreover, this was not a viable alternative if there is a co-occurrence of peak geosmin episodes and peak water demand in the future.

Figure 6.9: Percentage of Total Flow into Distribution System

Modification to raw water intake levels

One of the strategies listed in the EPA (June 2015) report to mitigate the cyanobacterial bloom before it impacts the WTP is to draw source water from multiple intake depths. This can also be used to minimize the intake of geosmin concentration on the surface or at certain depths. Lake Palestine intake facility includes a vertical turbine pumping station platform positioned over the lake. Regarding their ability to take water off different lake elevations, the 2001 plans show that each of the three pumps has its vertical suction pipe set at different elevations. However, this cannot be compared to the ability to pump water at different levels, as pumping from only one particular level only limits the total raw water discharge output. For example, if the geosmin level is lower at level three, where the pump three suction inlet is set, to continue pumping from level three alone, pumps one and two cannot be operated. This limits the total pump discharge from Lake Palestine’s raw water pumping station.

According to the City’s information, geosmin sampling has occurred at different levels on different occasions. The difference in the amount of geosmin present at each given level was observed to be slight to moderate. The City does switch to a different pump based on the need to potentially benefit from lowering the raw geosmin level. Although this strategy limits the raw water geosmin concentration to WTP, there is a need to implement a permanent solution to mitigate the geosmin issue at Lake Palestine WTP.

Lake Palestine & Lake Tyler Water Blending

Blending the raw water from Lake Tyler and Lake Palestine water will aid in reducing the T&O issues. There is always some blending of Lake Palestine and Golden Road treated water, which dilutes geosmin levels in the water delivered to the customers. This alternative focuses explicitly on blending the raw water from Lake Tyler and Palestine before entering the WTP. Lake Tyler water generally has no geosmin issues. This provides an opportunity for blending the two source waters to reduce geosmin concentrations in water delivered to the Lake Palestine treatment plant during high geosmin episodes. The concept of blending water sources is simple. For example, if 15 MGD were delivered from the Lake Palestine system, with a geosmin concentration of 100 ng/L and 15 MGD was delivered from Lake Tyler, with no geosmin concentration, blending would result in 50 ng/L as influent raw water geosmin concentration to Lake Palestine WTP.

Currently, the City produces 72.1 MGD, which includes 30 MGD from Lake Palestine WTP, 32 MGD from Golden Road WTP, and 8.7 MGD from operating water wells. According to its 2006 Master Plan, the City has a water rights permit issued by TCEQ (Permit No 1843) to annually withdraw 50,000 acre-feet/year (44.6 MGD) from Lake Tyler and Lake Tyler East. The two reservoirs have a total capacity of 74,125 acrefeet available for water supply and a maximum yield of 32,400 acre-feet/year (28.93 MGD). The average daily surface water use from Lake Tyler/Lake Tyler East currently is approximately 15 MGD annually.

Lake Palestine provides authorized surface water supplies for the cities of Dallas, Tyler, and Palestine, although only Tyler and Palestine are presently utilizing water from the reservoir. The City water rights designate they can take up to 60 MGD of raw water from the Upper Neches Municipal River Authority on Lake Palestine. Thus the City can produce 100.7 MGD with upgrades to its water treatment facilities.

This would reduce the load on the T&O treatment units, such as PAC and ozone, in Lake Palestine WTP. Additionally, this could also reduce Golden Road WTP capacity and output on a seasonal basis contingent on geosmin levels. The opportunity for blending requires additional pumping capacity at the Lake Tyler intake

Figure 6.10: Record Drawing-Raw Water Pump Section at Lake Palestine Intake

and the installation of a new raw pipeline from the Lake Tyler intake to Golden Road WTP.

To assess the economic feasibility of this option, Halff assumed the same raw water pipeline route as shown in the source switching option. Table 6.9 summarizes the total cost and annual cost of the project. The total cost includes the cost of facilities and associated project costs. Appendix E Part 6.5 provides a detailed cost estimate in 2019 dollars.

Modification to Existing Treatment Techniques-AOP (O3/H2O2):

Section 6.3 describes major technologies and their advantages and challenges associated with their application to address T&O issues due to geosmin in drinking water.

Studies have shown that ozone followed by biofiltration is usually sufficient for moderate MIB and geosmin concentration (<50 ng/L). Although PAC and ozone are effective in compacting issues due to geosmin, during extreme events, these may not remove sufficient T&O to avoid consumer complaints. Recent studies show that AOP effectively treats higher concentrations of T&O compounds. Ozone+Hydrogen Peroxide

AOP was determined to be the most viable overall option because it involved operational flexibility and an additional AOP barrier when required. Since Lake Palestine WTP has an existing ozone facility, this technology could be retrofitted or installed with minimal impact on the overall operation and effectiveness of the treatment system. The Ozone based AOP system would address current and future requirements based on taste and odor, color, and emerging contaminants.

The PFD in Appendix F shows how the proposed AOP system operates within the existing treatment train. The proposed AOP system consists of two Wedeco SMOevo 910 Ozone AOP Systems, each producing a maximum of 881 ppd of ozone day @ 30 MGD. Ozone is introduced as a pretreatment step before entering the existing treatment process, and the ozone is fed into a contact chamber with a minimum retention time of 10 minutes. When necessary, hydrogen peroxide can be fed before ozone addition through one static mixer with dual injection ports to generate hydroxyl radicals, which improves the oxidation process. If desired, peroxide could also be used at the end of the ozone contactor to remove any ozone residuals. The recommended

dosage required for two log reduction of Geosmin is 5.2 ppm of ozone. Wedeco recommends a 1:1 ratio of ozone:hydrogen peroxide for additional MIB/geosmin reduction during spikes. The following dosages are based on the existing geosmin levels and design capacity of the treatment plans and do not consider any water quality parameters.

The capital cost for ozone production increases proportionally to size, frequently listed by production capacity only. The operating ozone concentration and cooling water temperature also affect generator costs. Thus, confirming the dosage based on benchscale testing during the design phase is highly recommended. The ozone dosage should be designed to handle geosmin treatment on its own, reserving hydrogen peroxide injection for periodic MIB/geosmin spikes in the system. Based on the levels of geosmin the LPWTP deals with, it is unlikely there would be cost savings associated with downsizing the ozone generators and instead relying on constant peroxide injection.

Hydrogen Peroxide

Hydrogen Peroxide is a clear, colorless, odorless solution and can be purchased as a certified NSF standard 60-complaint product. Based on an ozone dose of 5.2mg/L and H2O2: O3 ratio, a flow rate of 30 MGD, 330 gph of hydrogen peroxide is required. Installation of hydrogen peroxide facility would include secondary containment, static mixers, metering, feed pumps, and double-contained HDPE buried piping and fittings.

UV protection for the hydrogen peroxide tanks, whether a small building or simple shades, is recommended to reduce the chance of hydrogen peroxide degradation. After approximately one year, hydrogen peroxide degrades significantly. It is recommended that regardless of the need for additional geosmin treatment, the City replenishes its peroxide supply annually, using the opportunity to ensure the transfer and retention of knowledge about the process among staff.

Industry Standards/Construction materials for ozone equipment

All rubber, most plastics, neoprene, ethylenepropylene-diene rubbers (EPDM), and aluminum are unacceptable for ozone use. The only acceptable

materials are 316 stainless steel, 305 stainless steel, glass, Hypalon, Teflon, and concrete. The generation of oxygen gas results in binding inside the feed pipes. The length of feed piping between storage tank and carrier water should be minimized to reduce the potential for gas binding problems. The arrangement should be made to collect and remove gas from the piping. Hydrogen peroxide concentration in carrier water is typically between 1 to 5%, where decomposition reaction does not cause problems.

Location of Ozone Application

Pre-ozone: ozonation of the raw water before the rapid mix. Benefits include disinfection, T&O, disinfection by-product reduction, reduction in coagulant dose, enhanced particle removal, and biological stability of filtered water.

Intermediate ozone: ozonation of settled water before filtration. Intermediate ozone addition is the preferred location in plants, especially where raw water quality is poor and the disinfection ozone dose is too high. In these plants, ozone is often added to an intermediate location to achieve disinfection only.

6.8 RECOMMENDATION AND CONCLUSION

Reviewing the four proposed options for dealing with geosmin levels from Lake Palestine, modifying the existing treatment system to accommodate AOP rises to the top. Source switching, directing water from Lake Tyler to the Lake Palestine WTP, has an incredibly high upfront cost associated with building a new raw water pipeline. On top of that, this method is rendered ineffective if high levels of geosmin coincide with peak demand. The same upfront cost is needed for water blending, and the same issue of solution permanence remains. As demand grows in the City, the geosmin levels after blending would continue to be far above the T&O threshold. Adjusting the raw water intake depth to bring in lower-geosmin water during high geosmin periods is a solution that would require expansion of the raw water pump stations and does not adequately address the issue of geosmin. Modifying the current treatment system is a smaller-scale upgrade that offers a permanent solution to geosmin-induced taste and odor issues.

The following are the recommendations from this chapter:

Ozone+ Hydrogen Peroxide AOP: It is recommended that a 1:1 ratio of ozone and hydrogen peroxide be used in tackling geosmin jointly at the Lake Palestine WTP. As mentioned in 6.7, the ozone should be designed to handle most geosmin issues on its own, reserving injection of hydrogen peroxide for the unusually high levels that tend to happen on a seasonal basis. However it is recommended that the City periodically run the hydrogen peroxide system during the off-peak geosmin seasons to maintain institutional knowledge on system operation. Appendix E part 6.6 shows Xylem’s tentative design of the AOP system. Pilot testing should be performed to adjust the dosing based on potential changes to the system. See the subsequent recommendations below on bench or pilot scale testing.

Location of Ozone Application: The existing treatment train at Lake Palestine will retrofit the existing process flow to allow for updated dosages. The ozone generators chosen should fit the same approximate footprint as the existing generators, proving no need for upgrades to the building itself. However, the existing fine bubble diffuser will be abandoned in favor of a side stream injection system. Retrofitting the contactor basin involves plugging the hole where the previous diffuser sits and installing basin nozzle manifolds, a process that similarly requires no change to the basin footprint. With the side stream injector system, a gas inlet mixes ozone with a side (bypass) stream of water before employing a flash reactor to reintegrate the homogenous mixture back into the main stream of water. The proposed treatment train at Lake Palestine will follow the same general process flow and site layout. Since both treatment trains are expected to ultimately handle 30 MGD, the physical footprint of the ozone systems should match. The proposed facilities for the new treatment train will accommodate the expansion from 15 MGD to 30 MGD by sizing the ozone building, for example, for future installation of ozone generators in addition to the ones included in the scope of this master plan. See Chapter 7 for more details on the future Lake Palestine WTP expansion phasing.

Location of Hydrogen Peroxide Application: It is recommended that a hydrogen peroxide static mixer

be placed upstream of ozone injection. This provides an opportunity for the City to consolidate hydrogen peroxide injection for both treatment trains by placing the mixer along the 54-inch raw water line before it tees off in different directions. Hydrogen peroxide can be stored in the “liquid bins” that are directly purchased. The proposed site design places the peroxide storage adjacent to the liquid oxygen tanks at the existing Lake Palestine WTP treatment train. The skid used for hydrogen peroxide is small and should not require a building to shield it from the elements. It is recommended that a manufacturer be present for the installation of the hydrogen peroxide skid and injection components.

Increase frequency of geosmin monitoring: Frequent geosmin monitoring, especially during peak geosmin season (December to March), helps treatment plant operators need to know when T&O episodes will occur and thus prepare the WTPs for an episode. Improved monitoring results help to optimize the use of PAC, ozone, and hydrogen peroxide in combatting T&O issues. The City is currently testing approximately once a week, an adequate frequency for a properly functioning system.The City may consider using an instrument that can test for 2-MIB, geosmin, and harmful algae blooms.

Automated system: There is not currently a reliable option that will allow the system to automatically regulate the ozone dosage in response to changes in geosmin levels. However, measuring TOC in the raw water entering Lake Palestine WTP is one option to monitor geosmin levels, indicating the potential need for supplemental hydrogen peroxide. Information about a TOC instrument can also be found in Appendix E Part 6.7. On the back end of the process, monitoring DO3 for decreasing levels can hint at the presence of cyanobacteria and suggest the need for a higher treatment dosage.

Monitor cyanotoxins: Many studies have highlighted the co-occurrence of T&O compounds with cyanotoxins. Thus, it is recommended to monitor cyanotoxin in lakes, especially during high geosmin episodes. Previous studies have neglected the importance of extracellular toxin release caused by the pre-oxidant application. Thus, care should be taken to adopt a treatment technique that does not aggravate cyanotoxin levels. A sonde installed at

Lake Palestine can monitor cyanotoxins at the source and provide qualitative feedback for the City to help inform its geosmin treatment. See Appendix E Part 6.7 for detailed information about what a potential instrumentation add-on may look like for these purposes.

Implement bench or pilot-scale studies: Elevated ozone demand and rapid decay will increase the design ozone dose. The ozone decay rate also impacts the contactor size and shape. Thus, bench or pilotscale studies should be conducted to establish design criteria and confirm the ozone+hydrogen peroxide AOP’s feasibility, and evaluate the ozone contactor size in Lake Palestine WTP. The incorporation of contactor design into the assessment of ozone dose is one of the important factors affecting the accuracy of scale-up using bench scale and pilot scale data.

Bench scale to full scale: In most cases, when the dose was unequal, the bench scale dose was less than the full scale measured dose within +/- 20%. Given this finding, a safety factor of at least 20% might be applied to bench scale dose assessment.

Maintain Existing PAC Unit during Retrofit: Although this study recommends implementing AOP using ozone+ hydrogen peroxide AOP as a primary treatment technique to compact T&O issues, it is proposed to maintain the existing PAC unit active throughout the construction. Thus, PAC could be used as a substitute during any rehabilitation work to the existing ozone system at Lake Palestine. Jar tests are recommended to test the effectiveness of various PAC types and doses, with the implementation of the carbon with the greatest capacity for removal of the target contaminants. Optimizing the PAC dosage is important since overdosing could result in excessive sludge production, reduced filter performance, and larger operating costs (EPA, 2014). However, once the ozone+hydrogen peroxide AOP system is in place and functional, the upkeep of PAC-related equipment is at the discretion of the City. At this point, the PAC unit could be removed. This report assumes future improvements will not include this upkeep, such as replacing the carbon feed system upon its anticipated expiration in 2039.

Side stream injection dissolution system: The existing contact diffuser at Lake Palestine WTP is set

to expire in 2032. Instead of replacing it with the same model, the setup will be upgraded to a side stream injection dissolution system. The side stream injector allows higher doses of ozone to be introduced to the water than the current diffuser. Retrofitting the existing contactor basin at Lake Palestine WTP will first involve plugging the existing outlet in the contactor basin where the previous diffuser sat. A new outlet will be cut into the basin for the side stream injector, which functions with a smaller overall footprint, avoiding the need for an entirely new contactor basin. The contractor overseeing this retrofit will need a structural engineer to review the existing design and direct the appropriate changes, but a new basin is not necessary.

Project Implementation timeline: It is recommended that major upgradation to existing ozone facilities should be planned during non-peak geosmin seasons such as April to November.

Cost to Retrofit Existing Treatment Train: The prices quoted hereafter are preliminary and nonbinding based on current market conditions. The quote for updated geosmin treatment materials alone is $2,173,975. This estimate accounts only for the cost of ozone generators, ambient monitors, side stream injection, field service, and the hydrogen peroxide dosing system. The quote received and included in Appendix F does not include the cost of associated engineering and contracting services. The entire CIP in Appendix I reflects the quoted numbers with added contingency to account for these costs, which comes to $3,043,565.

Cost of Equipment Required for Expansion of 15 MGD: The prices quoted hereafter are preliminary and non-binding based on current market conditions. The quote for geosmin treatment materials related to expanding the existing Lake Palestine treatment train

by 15 MGD is quoted at $3,105,875. This accounts for materials, freight, and limited field service but does not consider the cost of installation fully in place. The entire CIP, including costs for engineering and contracting, can be found in Appendix I and comes to $4,348,225.

Both of these costs assume that all process requirements, including electrical power, cooling water fill, and oxygen (if applicable), are provided by others.

Grant Potential: The Texas Water Development Board has announced its Emerging Contaminants Program, which is federally funded and administered through the existing Drinking Water State Revolving Fund. The replacement of two ozone generators may qualify for $1,022,000 of funding under this program. Updating the existing geosmin treatment system with new ambient monitors and a hydrogen peroxide dosing system may qualify for $853,000 in funding. Geosmin-related testing instrumentation such as monitors for TOC and cyanobacteria may qualify for $80,460. The pilot testing for these upgrades to the existing AOP system and implementing the system at the Lake Palestine expansion could potentially be covered under this program as well.

Geosmin is considered an indicator for cyanotoxins, the emerging contaminant included in this legislation. The program provides 100% principal forgiveness with no origination fees, allowing grant money outright for the planning, monitoring, design, land acquisition, construction, and pilot testing of the system.

7 Future Expansion of Facilities

The future water demand for Lake Palestine and Golden Road WTP are detailed in the Water Distribution System Master Plan Report. The existing and projected maximum daily demand for the years 2047 (25-year) and 2072 (50-year) are shown in Table 7.1. The City has enough raw water supply to meet maximum day demands at least through 2072. This chapter summarizes how this raw water supply will be divided for treatment between existing and future treatment infrastructure.

7.1 DEMAND SPLIT BETWEEN WTPS EXISTING

The system’s demands are met exclusively by production at the two WTPs. Lake Palestine WTP plant generally serves the fast-growing southern section of the City. Golden Road WTP fills the various downtown elevated storage tanks (EST), and Lake Palestine fills Copeland and GE ESTs. There is a boundary in the distribution system to demarcate the areas served by Lake Palestine and Golden Road WTP. However, this boundary is dynamic and shifts with the actual plant outputs. Exhibit 7.1 in Appendix G shows the WTP influence boundary line. Under typical operation conditions, the water pipes shown in blue are served by Lake Palestine WTP, and the orange served by Golden Road WTP. The water pipes shown in green are served by both WTPs. Operators aim to supply approximately 40% of daily system demands from Golden Road WTP and the remaining 60% of daily demands from Lake Palestine WTP.

As constructed, the existing Golden Road WTP is laid out in an imperfect, unintuitive way, reducing its efficiency and ease of operation. Due to its age, many

components are reaching their end of life and would be better replaced with newer versions that may not fit the same footprint as the current site. Constructing a new water treatment plant to eventually replace the Golden Road WTP would allow for upgrades that can ensure the plant is able to produce the maximum it’s expected rather than capping out at a low production rate as the current site does. The simplest option for this new location appears to be the adjacent parkland to the east, but politically and socially, it makes little sense to add the burden of removing and relocating a park. An alternate location would ideally focus on the raw water pipeline route currently supplying Golden Road, minimizing the distance of the new raw water pipeline that would need to be constructed. Placing the new ”Southeast WTP” south of the existing Golden Road location would be prudent, expanding infrastructure in the same direction as population growth and taking advantage of higher pressure spots in the distribution system.

However, the City is constrained by financial and political realities that can make capital investment for a new plant infeasible. Understanding the City may choose to continue investing significantly in the existing Golden Road plant, the recommended action is revitalizing it to reliably treat 28 MGD through the planning period and beyond. The limitations on land availability near Golden Road described above will require this restoration to be carefully planned to ensure all new components fit the existing physical space. Unfortunately it is beyond the scope of this master planning effort to conduct detailed field condition assessments of major mechanical equipment, structural elements, and the plant’s electrical system. Please see Chapter 8 for a flow chart that provides a path forward on finalizing the decision to extend the life of the Golden Road WTP, the recommendation referred to as Alternate 4. Until that path forward can be executed further and after discussion with City staff, it is assumed that this alternative is the most favorable option.

FUTURE

Over time, the City will complete a number of projects that cover a variety of necessary rehabilitations and

Table 7.1: Comparison of Firm Yield and Demand

replacements to existing plant infrastructure so that by the year 2032 Golden Road will be fully restored to a reliable 28 MGD capacity. By 2037 the City will execute the first phase of expanding the Lake Palestine WTP, adding an additional 15 MGD of capacity. This first phase would begin operations after the Golden Road reformation is complete. The City will execute the second phase of LP WTP expansion by 2057, adding an additional 15 MGD and allowing the Lake Palestine

plant to operate at its final full capacity of 60 MGD. At that point the two combined WTPs would provide a cumulative 88 MGD for the City, nearly maxxing out its current raw water yield from the two lakes. Table 7.2 outlines this data, and Graph 7.1 displays it visually. Process flow diagrams for the proposed treatment plant extensions can be found in Appendix H, in addition to the proposed site layouts.

Table 7.2: Comparison of Demand and Division of WTP Capacity

Note: 22 MGD is the typical production rate based on the WTP operator

Graph 7.1: Comparison of Demand and Division of WTP Capacity

7.2 FUTURE EXPANSION OF LAKE PALESTINE AND RESTORATION OF THE GOLDEN ROAD WTP

Over the next five years, the City will begin the rehabilitation of the Golden Road WTP. While Golden Road improvements are being designed and constructed over the next nine years, the existing Lake Palestine treatment train will receive minimal upgrades. Expected upgrades include replacing expiring parts and updates to the current geosmin removal system. Once improvements at Golden Road are implemented, construction will begin on a second train for the Lake Palestine WTP. At the end of the following five years, the Lake Palestine plant will operate at three-quarters capacity, the original train operating fully at 30 MGD and the new train operating at half-capacity 15 MGD. See Appendix H for a potential site layout for the Lake Palestine WTP expansion.

7.3 FUTURE EXPANSION OF RAW WATER PUMPS

The existing raw water pumps at Lake Tyler supplying Golden Road WTP will remain effective to continue to supply water to that plant. For Lake Palestine, however, the capacity is expanding and will require an additional pump to accommodate the new raw water line described in section 7.3. Since this expansion was anticipated during the original construction of the raw water intake, two vacant holsters are awaiting these new pumps. The new Lake Palestine treatment train is scheduled to go online by the end of 2037, and the pumps must be installed and functional by this point. One of these pumps, entirely constructed in place, is estimated at $1,253,000 in current dollars. The cost outline can be found in Appendix I.

7.4 TCEQ GUIDELINES WTP CAPACITY AND LOCATION

1. Based on current acceptable design standards, the total capacity of the public water system’s treatment facilities must always be greater than its anticipated maximum daily demand.

2. The water treatment plant and all pumping units shall be located in well-drained areas not subject to flooding and away from seepage areas or where the groundwater water table is near the surface.

3. Water treatment plants shall not be located within 500 feet of a sewage treatment plant or lands irrigated with sewage effluent. A minimum distance of 150 feet must be maintained between any septic tank drainfield line and any underground treatment or storage unit. Any sanitary sewers located within 50 feet of any underground treatment or storage unit shall be constructed of ductile iron or polyvinyl chloride (PVC) pipe with a minimum pressure rating of 150 pounds per square inch (psi) and have watertight joints.

4. Plant site selection shall also consider the need for the disposition of all plant wastes following all applicable regulations and state statutes, including both liquid and solid wastes or by-product material from the operation and/or maintenance.

5. Each water treatment plant shall be located at a site accessible by an all-weather road.

CLEARWELL CAPACITY AND LOCATION

The minimum clearwell, storage tank, and pressure maintenance capacity shall be governed by the requirements in §290.45 of this title (relating to Minimum Water System Capacity Requirements).

1. No public water supply elevated storage or ground storage tank shall be located within 500 feet of any municipal or industrial sewage treatment plant, or any land spray irrigated with treated sewage effluent or sludge disposal.

2. Insofar as possible, clearwells or treated water tanks shall not be located under any part of any buildings and, when possible, shall be constructed partially or wholly above ground.

3. No storage tank or clearwell located below ground level is allowed within 50 feet of a sanitary sewer or septic tank. However, if the sanitary sewers are constructed of 150 pounds per square inch (psi) pressure-rated pipe with pressure-tested, watertight joints used in water main construction, the minimum separation distance is ten feet.

4. No storage tank or clearwell located below ground level is allowed within 150 feet of a septic tank soil absorption system.

7.5 EMERGENCY POWER

The issue of emergency power was previously addressed in the Tyler Emergency Preparedness Plan (EPP) in 2021 and was not reevaluated. This report operates under the assumption that the City has begun initiating or plans to implement the recommendations in the EPP. Generally, those recommendations include a stand-by generator at Lake Palestine WTP and the associated raw water pump station and booster pump stations.

Currently, the raw water pump station generator is entirely manual and supplies power to the raw water pumps. The LPWTP generator is also fully manual and supplies power to the full plant, barring the highservice pumps for distribution. The high-service pump generator is fully manual and powers the high-service pumps. The only automatic generator in the Lake Palestine – LPWTP chain powers the admin and operations building. There is an opportunity for the City to fortify its backup power plan by installing automatic transfer switches (ATS) at its other generators. Detailed information about the current backup generators can be found in the City’s EPP.

7.6 GEOSMIN TREATMENT COMPONENTS

The specific geosmin treatment improvements detailed in chapter 6 include specific components, the costs for which can be found in the CIP in Appendix I. The quote for many of the geosmin treatment equipment, located in Appendix F, entails ozone generators, nitrogen skids, liquid oxygen vaporization equipment, ozone injection skids, hydrogen peroxide dosing, ambient ozone monitoring features, closed-loop cooling system, control panels, and associated spare parts. These spare parts are included to fortify the ozone injection system without installing an entire standby generator. Pilot testing before purchasing and installing the ozone generation system is critical to ensure the calculated dosage remains appropriate. That being said, the ozone generator currently identified is the SMOevo 910 model, which can produce a maximum of 881 ppd. One 9,000-gallon horizontal LOX tank and two ambient vaporizers are considered sufficient for the 15 MGD expansion north of the existing Lake Palestine WTP train. The nitrogen generator chosen is the General Air Products Base G3 model.

Not included in this quote is the cost of a contactor basin, which would need to be designed by a structural engineer in conjunction with the side-stream injection system. The cost estimate for the basin is based on an engineer’s review of the structural and mechanical plans for the existing basin at LPWTP to establish an expected cost. The quote does not account for the cost of a physical ozone building, the estimate for which was similarly achieved through a review of the existing plans by an architect. Since the sizes of the basin and ozone building are sufficient for 30 MGD flow at Lake Palestine WTP, they may be appropriate to use as a basis for expansion costs.

8 Water Facility Master Plan Recommendations and CIP

This Master Plan included an assement of the existing facilities at both Lake Palestine WTP and Golden Road WTP, including their associated raw water system. The evaluation included preparation of an asset inventory of major equipment items and a compliance check with with TCEQ design criteria. Additionally, many future characteristics such as water demand projections, service area population growth, and potential EPA regulatory requirements were developed and their impact on both plants was assessed as part of this Master Plan. Numerous recommendations have been made in this report based on the findings from these evaluations and predictions. This chapter summarizes the recommendations throughout the Master Plan and presents an implementation plan for executing them.

The significant issues evaluated in the Water Facility Master Plan include:

• Condition and criticality of current water treatment plant assets (Chapter 3)

• Drinking water regulations recently updated or anticipated for revision in the future (Chapter 4)

• Compliance of existing treatment units with TCEQ criteria (Chapter 5)

• Geosmin removal methods (Chapter 6)

• Compliance of existing treatment units at future demands with TCEQ criteria (Chapter 7)

• Future expansion of WTP (Chapter 7)

• Various rehabilitation projects (Chapter 8).

The overall project also addressed the water distribution system. Please refer to the companion reports prepared for this project that cover the water distribution system:

◦ Water Distribtuion System Asset Management Plan

◦ Water Master Plan of the Finished Water Distribution System

8.1 WATER FACILITY MASTER PLAN RECOMMENDATIONS

The improvements recommended throughout the Master Plan result from the evaluations listed above and others. These improvements have various

justifications. Some are recommended to comply with regulatory requirements, both existing and future. Some are recommended to potentially reduce operating and maintenance costs. Some are recommended to replace aging equipment, some to prepare for service area growth. This section summarizes the recommendations from the Facilities Master Plan.

A. ASSET INVENTORY (CHAPTER 3)

In Chapter 3 of this Master Plan, treatment units, components, and equipment at both plants were given an age condition and criticality score. The age condition is based on the installation date and anticipated unit life, while the criticality score depends on the equipment’s relative importance in the treatment process. In general, equipment with high scores for both age condition and criticality is anticipated to fail in the near future and will cause one or more nearby treatment processes to fail as well. It is recommended to verify the actual age, criticality, and condition of assets, starting with those with the highest ranking in Appendix A. Any changes in condition from what was determined in this effort should be updated in the analysis. Condition assessment should be considered an ongoing effort since the condition does change over time.

In most cases, it is recommended that these items first be inspected to confirm the estimated remaining life, and then adjustments to the asset inventory and other appropriate action be taken based on the inspection results. It is advised that the equipment recommendations described below be completed as soon as is practical. It is anticipated that equipment inspections will be relatively low cost and could potentially be covered in the treatment plant O&M budget. Development of asset inventory and assessing the condition and criticality is a dynamic process; thus, it is recommended to update GIS and/or CMMS inventory as new equipment is installed, rehabilitated, or replaced on existing assets. Only the major treatment units and their associated components/ equipment were recorded as assets in this study. For example, pieces of equipment such as valves are

included in this asset inventory only if they are part of the major process piping. It is recommended to include sub-components and sub-equipments associated with each treatment unit, such as mechanical, electrical, and civil units, in the list of assets.

The City should follow the step by step recommendations detailed in Section 3.7 of Chapter 3 before making any replacements, etc. related to the Asset Inventory assessment.

Recommendations for Lake Palestine WTP are listed below:

Have the following pipelines visually inspected to determine their condition. Based upon the condition assessment results, evaluate the need for pipeline rehabilitation or replacement or update the remaining service life.

◦ 48-inch DI raw water discharge line from Lake Palestine pumps to upstream of the water meter. A major part of this pipeline is above ground. See Appendix B Exhibit 2.1.

◦ 54-inch DI raw water line upstream of the water meter to 430 feet upstream of Lake Palestine WTP (at 54x48-in Tee Joint) See Appendix B Exhibit 2.1.

◦ 48-inch DI raw water line from 54x48-in Tee Joint to Lake Palestine WTP

Recommendations for Golden Road WTP are listed below:

Have the following pipelines visually inspected to determine their condition. Based upon the condition assessment results, evaluate the need for pipeline rehabilitation or replacement or update the remaining service life.

◦ 42-inch DI raw water discharge line from Lake Tyler pumps to 27-36-in tie-in location. A major part of this pipeline is above ground.

◦ 36 to 42-inch RC raw water line to Golden Road

WTP

◦ 27 to 30-inch RC raw water line to Golden Road

WTP

Equipment Replacement Schedule – Both Plants

An equipment replacement schedule is included in section 3.6 of Chapter 3. This equipment replacement schedule is based on the equipment’s year of installation and its anticipated life expectancy, which was developed in Chapter 3. Tables 3.6, 3.7, and 3.8 in Chapter 3 indicate the equipment needing replacement within the next year, five years, and ten years according to the installation date and anticipated life expectancy. While age can be a good approximation for equipment condition, it is recommended that the equipment in Tables 3.6, 3.7, and 3.8 be inspected by qualified equipment suppliers before replacement. The visual equipment inspection will better indicate the condition than elapsed time since installation. Section 3.7 of Chapter 3 details other features, some of which are scheduled for replacement in the CIP that ought to be evaluated and potentially replaced. Among these are the flocculator motors for Golden Road, which are currently not being used, and the filter media for the filtration basins at Lake Palestine.

Regarding recommendations related to the Golden Road WTP, in addition to the verification steps recommended in Section 3.7, the decision to move forward with any expenditures should align with the overall restoration schedule. If the City proceeds with Alternate 4 to fully restore Golden Road then it should anticipate replacing all expired equipment. However if the City determines after its assessments that there is greater value in building the proposed Southeast WTP, it is likely that most of the Golden Road WTP recommendations can be ignored. Most of the raw water system would continue to serve a proposed Southeast WTP and therefore should be implemented regardless of the alternate chosen.

B. REGULATORY REQUIREMENT FOR DRINKING WATER QUALITY (CHAPTER 4)

This Chapter provides information on the current regulation and potential regulations to be on City’s radar. It is recommended that the City review these potential regulations on the release dates, as mentioned in Table 4.5 in this chapter. The recommendations to be implemented from the Initial Operational Evaluation report by eHT, 2015 for Lake Palestine and Golden Road WTP are listed in Table 4.3 in Chapter 4.

C. WATER TREATMENT PLANT EVALUATION (CHAPTER 5)

Chapter 5 presents the results of the compliance of existing treatment units with the TCEQ criteria. Table 5.1 in Chapter 5 lists the equipment/units, not in compliance with the current TCEQ standards. The major treatment units in Lake Palestine WTP comply with the TCEQ Chapter 290 requirements. The abovementioned plant deficiencies do not require immediate attention. However, Halff recommends these plant deficiencies be resolved during any future upgradation works in these specific units.

D. GEOSMIN (CHAPTER 6)

Chapter 6 reviews the numerous geosmin treatment techniques available and evaluates the existing geosmin treatment unit at Lake Palestine WTP. Due to the high concentration of geosmin in Lake Palestine water, AOP using the Ozone /H2O2 process was determined to be the most viable overall option as it involved operational flexibility and an additional AOP barrier when required. The following are the recommendations from this chapter:

Install AOP using Ozone /H2O2: Ozone will serve as the primary treatment for geosmin with hydrogen peroxide available for supplemental use in high geosmin periods. The process flow for the ozone system will remain the same, with the caveat that the existing fine bubble diffuser will be replaced by a side stream injector that allows for a higher dosage of ozone to be mixed into the water. This master plan assumes the City does not choose to make this replacement alongside the ozone generator replacement, scheduled to happen in 2023. The contact diffuser is not set to expire until 2032, which means the City would continue using the current ozone dosage for eight years before the system is capable of achieving the taste and odor results. While the hydrogen peroxide system will be used more frequently during the peak geosmin seasons, it is recommended that the City run it periodically during off-peak seasons to maintain institutional knowledge on system operation.

This report recommends promptly beginning pilot testing to confirm appropriate ozone dosage and formally beginning a proposal to replace the ozone generators. It’s also recommended that the City begin the process of having a contractor assess

the engineering requirements to retrofit the current contactor basin to the new side stream injection system. The hydrogen peroxide implementation is currently scheduled for 2027, meaning the existing PAC setup will continue to provide supplementary geosmin treatment during high-concentration periods until the peroxide system is functional.

Location of Ozone Application: Ozone will continue to be applied as raw water approaches the treatment train, intercepting it as it enters the contact basin.

Location of Hydrogen Peroxide Application: The hydrogen peroxide static mixer will be placed upstream of ozone injection, ideally along the raw water line, before it tees off in the different directions of the two LPWTP trains. This consolidation is not crucial; separate static mixers could be placed on the two raw water lines headed toward each treatment train if the City decides to spend more money to keep the systems separate.

Increase frequency of geosmin monitoring: Frequent geosmin monitoring, especially during peak geosmin season (December to March), helps treatment plant operators need to know when T&O episodes will occur and thus prepare the WTPs for an episode. Improved monitoring results helps to optimize the use of PAC, ozone, and H2O2 in compacting T&O event. Geosmin testing should be seasonally based, occurring more often in the winter season. The City is currently testing approximately once a week, an adequate frequency for a properly functioning system.The City may consider using an instrument that can test for 2-MIB, geosmin, and harmful algae blooms.

Automated system: Instead of a system that automatically adjusts ozone, the City can pursue the implementation of TOC testing upstream of the WTP or DO3 measuring downstream of the ozone contact basin.

Monitor cyanotoxins: Many studies have highlighted the co-occurrence of T& O compounds with cyanotoxins. Thus, monitoring cyanotoxins in the lakes is recommended, especially during high geosmin episodes. Previous studies have neglected the importance of extracellular toxin release caused by pre-oxidants’ application. Thus, care should be taken to adopt a treatment technique that does not aggravate cyanotoxin levels. Additional monitoring for TOC can

also prove helpful to adjusting geosmin treatment. Additional information about specific instruments can be found in Appendix E Part 6.7.

Implement bench or pilot-scale studies: Elevated ozone demand and rapid decay will increase the design ozone dose. The ozone decay rate also impacts the contactor size and shape. Thus, bench or pilotscale studies should be conducted to establish design criteria, confirm the feasibility of AOP using Ozone / H2O2 and evaluate the ozone contactor size in Lake Palestine WTP. The incorporation of contactor design into the ozone dose assessment is an essential factor affecting the accuracy of scale-up using bench scale and pilot scale data. Bench scale to full scale: In most cases, when the dose was unequal, the bench scale dose was less than the full scale measured dose within +/- 20%. Given this finding, FOS of at least 20% might be applied to bench scale dose assessment.

Maintain Existing PAC Unit: Although this study recommends implementing ozone + hydrogen peroxide AOP as a primary treatment technique to compact T&O issues, it is proposed to maintain the existing PAC unit active throughout the construction. Thus, PAC could be used as a substitute during any rehabilitation work to the existing ozone system at Lake Palestine.

Side stream injection dissolution system: Replace the existing contact diffuser at Lake Palestine WTP with a side stream injection dissolution system, allowing higher ozone dosing. An engineer who understands the structural changes can retrofit the current contactor basin.

Project Implementation timeline: It is recommended that major upgrades to existing ozone facilities should be planned during non-peak seasons, such as April to November.

Grant Potential: The TWDB Emerging Contaminants Program provides an opportunity for the City to get $1,955,460 in capital costs related to geosmin testing covered. Pilot testing for the AOP system could also potentially be covered by funding through this program, should the City pursue it.

E. FUTURE PLANT EXPANSION (CHAPTER 7)

This chapter reviews water demand projections as a critical factor in determining the timing of future plant

expansions. The projected water demand in the year 2072 is 82 MGD. The following recommendations are made in this chapter to meet the projected demand: Immediately begin assessments of Golden Road WTP to determine the rehabilitation necessary to operate full time at 28 MGD by 2032. The City has made the initial decision to proceed with Alternate 4, reformation of Golden Road. The first step of Alternate 4 is gathering more information about the plant’s condition to reaffirm the City’s choice of alternate. The choice to pursue full restoration of Golden Road should be made with a complete understanding of what elements must be replaced and how the changes can be coordinated. Depending on the results of detailed electrical and mechanical assessments, the City can determine whether the financial cost and delicate nature of managing operations during shutdowns is the appropriate decision. If after evaluations the City opts to remain with Alternate 4, the option that restores Golden Road to maximum output, it should develop a schedule for improvements and begin as soon as possible. Equipment, particularly older components and those that have reached their end-of-service life at Golden Road should be inspected regularly. The restoration schedule should be revisited after every major improvement or after observing rapid deterioration of an asset’s condition. Growth and its impact on demand in the City should be monitored to ensure the plant’s restoration is on-schedule to provide capacity. The City should consider evaluating its emergency water conservation plan to effectively communicate with residents and industry if the need arises.

Expand the Lake Palestine WTP by constructing in two separate 15 MGD phases a full 30 MGD treatment train to the north of the existing one, where the City already owns the land for this purpose. The City does not need to resize any facilities since the two treatment trains will handle the same capacity, and the site layouts can remain largely the same. See Appendix H for a proposed site layout. The existing raw water line to the current treatment train at Lake Palestine WTP includes a stub-out that will be utilized for this addition. Approximately 1,000 feet of 48-inch pipe will be constructed connecting the new treatment train

to the water supplying the first. The raw water intake at Lake Palestine includes vacant holsters in which new vertical turbine pumps will be placed to serve the second treatment train.

Follow through on recommendations made previously in the City’s EPP. Fortifying critical infrastructure with generators enabled with automatic transfer switches (ATS) can improve the overall simplicity of operating during emergencies. This report does not elaborate on the benefits of implementing ATS or other backup generator power for specific system components; please see the EPP for further detail.

8.2 WATER FACILITY MASTER PLAN CAPITAL IMPROVEMENT PLAN

The recommendations developed throughout this Master Plan identified several future capital projects. Capital improvement projects were added to a capital improvement plan with an OPCC and implementation year. One item scheduled for the 2023 CIP is an overall assessment of the Golden Road plant resulting in a report. The goal of this assessment is to establish the full scope of repairs needed to keep the plant functional, which of those must occur immediately versus being put off, and identify potential costs

associated with each repair. Similarly, the raw water lines serving both Golden Road WTP and Lake Palestine WTP should have their condition evaluated under their own CIP projects.

The costs presented in the CIP are planning-level costs to prepare yearly budgets, and cost information for each project was calculated in 2022 dollars. The specific projects included stem from the Asset Inventory (Appendix A), as the scope of this master plan does not encompass a detailed condition assessment on which to base a Golden Road restoration plan. The assumptions for the planning level costs in Appendix I are based on the uniform costing model (UCM) for the Regional Water Planning by TWDB, inputs from the manufacturer, and the engineer’s experience on previous projects. This appendix provides an in-depth overview of the methods and assumptions that form the basis of cost estimates included in this report and its appendices. An explanation of the TWDB spreadsheet methods and assumptions can be found on the TWDB website titled “Uniform Costing Model User’s Guide Version 2.0,” with a preparation date of November 2018. Below in Table 8.1 is a general overview of the recommended capital improvements organized by estimated year of completion. The projected future costs are based on annual 3% inflation. Table 8.2 outlines the current CIP improvements on the City’s books affecting the Water Facilities.

Table 8.1: City of Tyler Proposed Water Facilities CIP

Note: The City has expressed intent to rehabilitate Golden Road Clariflocculators 3 and 4 by 2025. Their omission from this table is based on this understanding. All costs represent the present value.

1 The need, cost, and schedule of these projects are subject to change based upon the results of the Plant-Wide Assessment. The CIP should be updated once the assessment is complete and the results analyzed.

2 Timing of new High Service Pump Station is triggered by the City’s decision to start up the proposed Lower Pressure Plane

Table 8.2: City of Tyler Current Water Facilities CIP

Note: The City has expressed intent to rehalbilitate Golden Road Clariflocculators 3 and 4 by 2025. Omission from the TWU budget provided for this report is the basis for its absence in this table.

The sum of the costs in the table above, $22,113,891, is the budgeted expenditures provided in the TWU budget. The $194,834,705 presented in Table 8.1 is recommended to be spent over the 25-year period until 2037, unless the assessments suggest otherwise. These two sums present a grand total of $216,948,596 for the specific itmes included in the tables above. Items for which a cost estimate were not determined are marked as “TBD” and are not included in this grand total.

The City may choose to pursue grant opportunities for the design and construction of the Lake Palestine WTP expansion under the Water Infrastructure Finance and Innovation Act (WIFIA). Qualifying projects are at least $20 million and the maximum portion of eligible project costs the WIFIA can fund is 49%. Improved geosmin treatment highlights this expansion as a potentially qualifying project due to its reduction of exposure to emerging contaminants like cyanobacteria.

8.3 NON-CIP RECOMMENDATIONS

Outside of recommendations included in the CIP, the City should look to stay on top of operational and maintenance-related upgrades. These recommendations often overlap with emergency preparedness but can be crucial for day-to-day operations. Emphasizing transfer of knowledge from more tenured employees to newer ones is critical to fortify the utility against the “silver wave” of retirementage employees leaving the workforce. Implementing a system to regularly cross-train current employees is another way to reduce the potential for knowledge gaps and lapses in daily operations. While not explicitly evaluated in this master plan, keeping IT professionals actively involved in the maintenance and upgrade decisions is highly recommended. With cybersecurity risks consistently on the rise, a well-funded IT team is instrumental in maintaining network security.

As detailed in chapter 3, there are several critical items on which the Utility should keep a close eye. For items associated with the existing Golden Road WTP, the City must decide which components they would prefer to replace before failure versus those they intend to repair or replace on an emergency basis. Based on the assumed location for a new Southeast WTP, certain high-risk critical elements, such as the raw waterlines, would be replaced in advance or in conjunction with the construction of the new WTP. If the standpipes are expected to remain in use with the new Golden Road WTP, then replacing those is also considered a high priority. Pipes within the plant itself will continue to expire while the plant remains functional, and the City must remain aware of these to either intercept high-risk failures or remediate them after occurring. High-risk pipes include the 24-inch and 36-inch DI coagulated water pipes, the 33-inch RC drain pipe, and the 48inch RC clarified water pipe. The flocculator motors at the existing Golden Road plant are not functional and should be repaired or replaced to working condition while the plant remains productive. Other items that are set to expire at Golden Road WTP soon include clariflocculator basin #2, clear well #1, the 12-inch surge anticipator valve and the 12-inch surge protector valve, ad the raw water meter.

More of the replacements associated with Lake Palestine WTP have been noted in the CIP, such as its raw water lines. The fittings must also be replaced during these upgrades. The City has budgeted to replace the filter media in filtration basins at Lake Palestine WTP, which allows the City to observe performance differences and institute a regular schedule for replacement per the manufacturer’s recommendations. Most elements of the Lake Palestine plant have been included as necessary in the CIP, but internal piping between plant functions was generally excluded and should be replaced when needed.

8.4 ALTERNATIVES TO EXTENDING THE LIFE OF GOLDEN ROAD WTP

The formal recommendation remains Alternate 4, which poses that Golden Road can be restored to its maximum rated capacity of 28 MGD. The first step of this plan is to gather information about the costs, labor, and time required for a full restoration and confirm the

City finds the greatest value in this alternative. Given the unpredictable nature of costs and labor availability, it is prudent to have a contingency plan in the event that the City decides it does not find the greatest value in remaining with Alternate 4. The plans which explore this potential are Alternates 1, 2, and 3. Of these three alternative choices, Alternate 1 is the preferred choice.

A. ALTERNATE 1

Under Alternate 1 a new Southeast Water Treatment Plant should be constructed and Golden Road WTP abandoned along the phased schedule described below. This recommendation recognizes that without 28 MGD Golden Road in commission, the proposed Southeast WTP is not a wish list item but a long overdue investment in the City’s future growth. With projected growth in Tyler occurring largely to the south, the need for a new Water Treatment Plant is a gleaming opportunity to transition treatment operations to a more hydraulically ideal location.

The new Southeast WTP would be constructed in two 15 MGD phases, keeping Golden Road online with a lower production rate until the full 30 MGD is in operation. After the first 15 MGD phase is online in 2027, there will be three operational plants; once the second 15 MGD is completed in 2032 Golden Road will be abandoned, and the City will return to operating two WTPs in total. Limit equipment replacements at the existing Golden Road WTP to those critical to maintaining operations. The new WTP site should utilize the existing raw water pumps and pipelines. Finding a location south of the existing GRWTP prevents the City from needing larger raw water pumps to supply water to the treatment plant and allows the distribution model to capitalize on the remaining head by supplying water where the City expects growth. The new 30 MGD Southeast WTP will produce approximately half the City’s needed water while the Lake Palestine WTP undergoes expansion.

A new raw water pipeline will need to be constructed, teeing off the existing one and extending to the new Southeast site. The length of this pipe should be minimal and depends on the distance between the chosen site and the existing raw water pipeline. New raw water pumps are not needed at Lake Tyler unless the new water treatment plant is placed such that it increases the overall head loss from the intake location.

B. ALTERNATE 2

This schedule proposes more modular action on Southeast WTP construction, keeping with the original 2027 target date but instead for a smaller first phase of 7.5 MGD. This alternative assumes no change to the recommended timeline for expanding Lake Palestine WTP. A second 7.5 MGD phase is scheduled for use by 2042, and a third 15 MGD phase for 2047. This schedule requires Golden Road to maintain a capacity of 22 MGD via continued capital rehabilitation expenditures until 2037 and 15 MGD until the full Southeast capacity is built out in 2047.

C. ALTERNATE 3

Alternate 3 explores delayed action on Southeast WTP, relying as long as theoretically possible on Golden Road WTP to assist production. Delaying the Southeast plant requires an expedited timeline for expanding Lake Palestine WTP, having its first 15 MGD phase online by 2027, to keep up-to-date with City growth, particularly to the south. Southeast would be constructed in two phases – one 15 MGD online in 2042 and the other 15 MGD online in 2057. This schedule requires Golden Road to maintain a capacity of 22 MGD via continued capital rehabilitation expenditures until 2042 and 15 MGD until the full Southeast capacity is built out in 2057.

D. ANALYSIS OF ALTERNATES 1 THROUGH 3

Comparing these three alternates involves more than the capital cost of facilities projects themselves. Those impacts must be evaluated since water treatment facilities function within the larger distribution system. Hydraulic efficiency and other operational strains are considered below. Land planning is also discussed as one of the largest capital components not involved in this report’s estimations.

In advance of a new Southeast WTP, a raw water line would need to be constructed that diverts flow from the old location to the new one. Since the overall capacity between the two WTPs remains the same, there is no reason to provide an entirely new raw water line beginning at the source. A proposed raw water line would tee off of the existing line near the chosen site for the new Southeast WTP and likely consist of a pressure pipe. The raw water pipeline from Lake Palestine to the Lake Palestine WTP was

initially sized to accommodate the future need for 60 MGD of conveyance, so the bulk of that length would only experience upgrades as the pipe expires. The original plans also included a stub-out near the existing treatment train that is intended to serve the expansion to the north. The new raw water pipeline for the Lake Palestine WTP expansion is limited to approximately 1,000 feet of 48-inch pipe.

CAPITAL COSTS

As outlined in Table 8.3, the capital costs associated with Alternate 1 total approximately $357 million. Adjusting the three line items associated only with the design and construction of the treatment plants gets equivalent estimates for Alternates 2 and 3. Bear in mind any costs not associated with these items, such as pipelines or new geosmin treatment components, have not been included in this adjustment. The purpose of the adjustment is to clarify the difference in futurevalue costs by delaying the pursuit of a new WTP, were that option chosen. Table 8.3 outlines the change in the treatment plant costs based on the schedules described in each alternate. Alternate 2 adds about $55 million to the cost of the recommended plan, essentially spending this additional money for the benefit of building the Southeast plant in a more modular manner, staggering its costs over a longer period of time without disrupting the Water Distribution Master Plan. Alternate 3 adds about $142 million in treatment plan capital cost alone, spending this additional money to delay Southeast WTP entirely. As is described in the following section, this figure does not represent the full cost of choosing Alternate 3. The Water Distribution Master Plan would be greatly disrupted by the scheduling in Alternate 3, requiring an overhaul of the model to accommodate an accelerated schedule for certain projects that would otherwise occur further in the future. Alternate 4 is included in this table, but the total costs are incomplete and it is infeasible to predict the full amount of capital expenditures required at Golden Road WTP for a complete rehab.

Table 8.3: Capital Costs by Alternate

Note: Costs shown are adjusted to estimate future inflation The capital cost for Alternate 4 is incomplete, pending the required assessments.

1 Total cost estimations do not include associated Golden Road improvements. They also do not include land acquisition costs.

DISTRIBUTION MASTER PLAN

Water treatment facilities do not function in a vacuum; each of the three alternates described above results in a ripple effect of capital projects required to make the actual distribution of water possible. If the City opts to pursue construction of a new Southeast plant, the distribution model provides insight into how CIP projects may be rescheduled to accommodate staggered or delayed construction of the Southeast WTP. Since the southeast portion of the City is expected to experience larger growth in the immediate future, this analysis focuses on this area and assumes no other growth.

Alternates 1 through 3 do not suggest improvements to Golden Road that bring its functional treatment capacity up to its rated capacity of 28 MGD due to distribution limitations. The Water Distribution Master Plan is designed to accommodate long-term growth in the southeast part of the city in a hydraulically efficient manner. To make Alternate 4, and therefore the longterm operation of Golden Road viable, the Distribution System Master Plan includes capital improvement projects explicitly for this purpose. The additions must be executed to fully use a reformed Golden Road. Without these projects, the amount of money poured into improving Golden Road is rendered useless; it is

otherwise not feasible to distribute a full 28 MGD to its intended destinations within the distribution system envisioned by the Distribution System Master Plan.

Alternates 1 and 2 do not require the distribution additions necessary for Alternate 4 according to the Distribution Master Plan. Alternate 3, however, requires the plan to be reworked to expedite certain CIP items that improve transmission capabilities to growth in the southeast. A 24-inch line included in the Water Distribution Master Plan under Category F improvements would need to be constructed sooner than planned to allow more conveyance to this area from Lake Palestine WTP; this project is estimated at $1,751,000. A project from Category E of the Distribution Master Plan proposes an additional pressure-reducing valve (PRV), allowing the system to accommodate an additional 4.5 MGD, which translates to approximately 3,000 single-family homes; this project is estimated at $4,320,000. This analysis of the distribution model assumes no additional growth in other areas.

HYDRAULIC EFFICIENCY

As south Tyler experiences a higher rate of population growth, the benefits of having a more localized treatment plant are clear in terms of energy and costs expended to pump water to a different part of the city than where it is treated. Alternates 1 and 2 capitalize on this growth to transition southeast operations to an ideal location as soon as possible. Alternate 3 delays this inevitable transition by 15 years, requiring the distribution projects explored above to come online sooner than planned so the system can expend more energy to get water to its needed destinations. Alternate 4 aims to substitute localized production with new additions to the distribution system that allow more water transmission.

OPERATION AND MAINTENANCE

A higher number of facilities means higher maintenance costs and more man-hours required. With the current “silver wave” of experienced professionals retiring from the workforce expected to continue, water utilities must be vigilant in establishing knowledge transfer to younger employees. Golden Road is a unique facility that relies on makeshift solutions by operators who understand the plant’s maintenance history. By contrast, Lake Palestine features an efficient modern layout that will be emulated in the LP WTP expansion and the new SE WTP if applicable. Maintaining Golden

Road for a longer period necessitates regular training to recognize its unique issues and resolve them promptly. Recommending Alternate 4 necessitates the City establish a plan to secure knowledge about current Golden Road’s operations. Cross-training staff is both recommended and effective, but having a physical guide to aid operation should be prioritized. The restoration of Golden Road should seek to eliminate site-specific quirks where possible and allow future operators to transition between plants with relative ease. As Alternate 4 proceeds and Golden Road is improved, the staff should continue to update the operational guide.

Alternate 1 minimizes the time the City operates three separate treatment facilities (and consequently the time Golden Road remains online) to ten years. Alternate 2 proposes operating three facilities for twenty-five years, with Golden Road offline in 2047. Alternate 3 proposes three online facilities for thirty-five years, with Golden Road offline in 2057. Alternate 4 eliminates the expectation for three treatment facilities altogether.

LAND ACQUISITION

Land costs in US cities reliably increase in value, impacting the total cost of a project should land acquisition be delayed. Land availability can also be unpredictable, potentially forcing a facility into a space that makes operation trickier or pricier. Alternates 1 and 2 necessitate the City to locate and purchase a suitable plot immediately. Alternate 3 technically allows this to be put off, but delaying this element of a future project is inadvisable. It is highly recommended that the City identify its choice property and act quickly. Alternate 4 does not require acquiring any new land for treatment needs.

Golden Road is set to be out of use by 2032 in Alternate 1, 2047 in Alternate 2, and 2057 in Alternate 3. This represents an opportunity for the City to identify another public use for this centrally located land. Under Alternate 4 this land will continue to be used for water treatment.

Table 8.4 below summarizes how each alternate fares when viewed through the lens of the factors described above. Alternate 4 is included in this comparison since overall capital costs are not included. As stated previously, a comparison between all four alternates based on capital costs is infeasible until full assessments of Golden Road are complete.

Table 8.4: Analysis by Alternate

This report recommends a full assessment of Golden Road WTP be scheduled immediately to identify the full scope of the plant’s condition and needed repairs. The City has already enlisted others to begin evaluating the electrical component of Golden Road. The City should also perform a mechanical assessment to identify improvements that can contribute to the plant functionally outputting 28 MGD regularly.

The recommended assessment would supplement this approximation with any costs associated with electrical and SCADA improvements, along with any non-inventoried items needing attention. The information gained from the recommended assessment will likely allow for a more accurate assessment of the improvements and rehabilitation necessary at Golden Road and their associated capital expenditures. Based on current information, it is believed that significantly more capital expenditures will be needed under Alternates 3 and 4, perhaps much more than the

$44 million estimated by the Asset Inventory. Overall Golden Road WTP has proven a temperamental asset whose life expectancy is difficult to accurately predict even with the greatest care taken by maintenance staff. Any attempts to extend the life of Golden Road include inherent financial risk due to the unpredictable nature of investments needed.

If future information necessitates a change in plans away from Alternat 4, the Southeast Plant alternative would be implemented as described in either Alternates 1, 2, or 3. Under any of these options, the City will ultimately abandon the existing Golden Road WTP in full, transitioning its capacity to a brand new 30 MGD WTP located on an assumed site approximately 4 miles southeast or upstream over ten years. In the event the City does not acquire this particular property, an alternate location along the existing raw water pipeline route from Lake Tyler will be chosen, and associated costs will be updated. The layout of this new treatment

plant, “Southeast,” will match the general layout of the Lake Palestine plant, modifying it as necessary to fit the buildable space. The 30 MGD capacity at Southeast will be split into two or three separate construction phases, depending on the schedule chosen, to gradually increase production to meet growing demand. The City will expand the Lake Palestine WTP, adding 15 MGD of capacity in the first phase, with a second 15 MGD following. This completed project doubles the Lake Palestine plant’s treatment train capacity to 60 MGD. This second train would begin operations after the Golden Road transition is complete and would take approximately 25 years to operate at full capacity. At that point, the two combined WTPs would provide a cumulative 90 MGD for the City, maxing out its current raw water yield from the two lakes.

Figure 8.1 below reiterates that the Golden Road assessment is a crucial first step that allows the City to

make an informed decision about its future.

Beyond choosing an alternative by which to design and construct new treatment infrastructure, the City must revisit its master plans periodically. Both this Water Facilities Master Plan and the Water Distribution Master Plan necessarily make assumptions that are subject to change. The volume of growth in Tyler along with the locations and densities of said growth are capable of changing year by year. The final recommendation in this report is that the City update its asset inventory regularly and the master plans every five years. The City should provide its resulting CIP plans to Region I at the same interval to allow the Updating the master plans with current information about the condition of components and necessary improvements at Golden Road is particularly critical. The City’s interest in keeping Golden Road afloat will require careful scheduling and distribution of capital expenditures.

Figure 8.1: Recommended Order of Operations

APPENDIX A

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places.Notes from record- Filters 4-8 rehabilitated in 2022. Maximum of 1 filter shall be removed from service at anytime. Note from record, Filter pipe gallery and filter surface wash modified in 1993

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places. Notes from record- Filters 4-8 rehabilitated in 2022. Filters 6-8 are experiencing some mal-distribution. Maximum of 1 filter shall be removed from service at anytime. Note from record, Filter pipe gallery and filter surface wash modified in 1993.

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places. Notes from record- Filters 4-8 rehabilitated in 2022. Filters 6-8 are experiencing some mal-distribution. Maximum of 1 filter shall be removed from service at anytime. Note from record, Filter pipe gallery and filter surface wash modified in 1993

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places. Notes from record- Filters 4-8 rehabilitated in 2022. Filters 6-8 are experiencing some mal-distribution. Maximum of 1 filter shall be removed from service at anytime. Note from record, Filter pipe gallery and filter surface wash modified in 1993

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places. Maximum of 1 filter shall be removed from service at anytime. Note from record, Filter pipe gallery and filter surface wash modified in 1993. UPDATE: Filter rehabilitation to be complete by FY 2027. The scope of this asset inventory focuses on larger-scale components, in this case the basin itself, and does not reflect detailed condition of the media, troughs, underdrains, etc.

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places. Maximum of 1 filter shall be removed from service at anytime. Note from record, Filter pipe gallery and filter surface wash modified in 1993 UPDATE: Filter rehabilitation to be complete by FY 2027. The scope of this asset inventory focuses on larger-scale components, in this case the basin itself, and does not reflect detailed condition of the media, troughs, underdrains, etc.

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places. Maximum of 1 filter shall be removed from service at anytime. Note from record, Filter pipe gallery and filter surface wash modified in 1993. UPDATE: Scheduled for rehabilitation October 2024. The scope of this asset inventory focuses on larger-scale components, in this case the basin itself, and does not reflect detailed condition of the media, troughs, underdrains, etc.

Pipe 30 deep has been removed & replaced. Total CL has been monitored. CL residual is too high in some places. Maximum of 1

GOLDEN ROAD ASSET INVENTORY

LAKE PALESTINE ASSET INVENTORY

wont

have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.Floc basins work well; runs largely by

Sometimes these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

Sometimes these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

3 Sometimes these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

2 3 Sometimes these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.Floc basins work well; runs largely by gravity

these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

Sometimes these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others

wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

wont operate, have to be

out

dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.Floc basins work well; runs largely by gravity

these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

LAKE PALESTINE ASSET INVENTORY

2

these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

Sometimes these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

Sometimes these wont operate, have to be cleared out and dried out. Aerial wiring add-on was begun but not completed. Others are wired through mhs. Goal is to get 100% of conduits to be aerial. Flocculators are generally well-designed.

Not happy about sed

2

every 3-24 hours (varies, basin dependent) typically is sufficient.Concrete has some cracking and leaking, normal ans expected. Causes drips at

Not happy about sed basins. Have learned to clean these once a year, a basin takes about 1 week totaling a minimum full cleaning time of 3 weeks. Issue is that drain is higher than floor bottom. Previous staff did not generally clean adequately. Blowdown system works great. Doing a "blowdown" once every 3-24 hours (varies, basin dependent) typically is sufficient.Concrete has some cracking and leaking, normal ans expected. Causes drips at most.

2

there was a single CL injection point. They've now added 2nd CL inj point DS of basin #1. Polymer is now distributed across all filters. Receive gravity flow from sed basins. Anthracite coal. Heaviest loading on upper filters (5-8). Filters have original filter media, target life cycle is 7yrs but currently 15yrs in service. Pneumatic valve operators pose some issues. Electric would be better, pneum have challenges with modulation.

First comes filter trough. Originally there was a single CL injection point. They've now added 2nd CL inj point DS of basin #1. Polymer is now distributed across all filters. Receive gravity flow from sed basins. Anthracite coal. Heaviest loading on upper filters (5-8). Filters have original filter media, target life cycle is 7yrs but currently 15yrs in service. Pneumatic valve operators pose some issues. Electric would be better, pneum have challenges with modulation.

First comes filter trough. Originally there was a single CL injection point. They've now added 2nd CL inj point DS of basin #1. Polymer is now distributed across all filters. Receive gravity flow from sed basins. Anthracite coal. Heaviest loading on upper filters (5-8). Filters have original filter media, target life cycle is 7yrs but currently 15yrs in service. Pneumatic valve operators pose some issues. Electric would be better, pneum have challenges with modulation.

3 First comes filter trough. Originally there was a single CL injection point. They've now added 2nd CL inj point DS of basin #1. Polymer is now distributed across all filters. Receive gravity flow from sed basins. Anthracite coal. Heaviest loading on upper filters (5-8). Filters have original filter media, target life cycle is 7yrs but currently 15yrs in service. Pneumatic valve operators pose some issues. Electric would be better, pneum have challenges with modulation.

3 First comes filter trough. Originally there was a single CL injection point. They've now added 2nd CL inj point DS of basin #1. Polymer is now distributed across all filters. Receive gravity flow from sed basins. Anthracite coal. Heaviest loading on upper filters (5-8). Filters have original filter media, target life cycle is 7yrs but currently 15yrs in service. Pneumatic valve operators pose some issues. Electric would be better, pneum have challenges with modulation.

3 First comes filter trough. Originally there was a single CL injection point. They've now added 2nd CL inj point DS of basin #1. Polymer is now distributed across all filters. Receive gravity flow from sed basins. Anthracite coal. Heaviest loading on upper filters (5-8). Filters have original filter media, target life cycle is 7yrs but currently 15yrs in service. Pneumatic valve operators pose some issues. Electric would be better, pneum have challenges with modulation.

comes filter trough. Originally there was a single CL injection point. They've now added 2nd CL inj point DS of basin #1. Polymer is now distributed across all filters. Receive gravity flow from sed basins. Anthracite coal. Heaviest loading on upper filters (5-8). Filters have original filter media, target life cycle is 7yrs but currently 15yrs in service. Pneumatic valve operators pose some issues. Electric would be better, pneum have challenges with modulation.

system operates satisfactorily; air scour is an issue. Staff must wash filters manually. This is not considered a significant issue, but an automated backwash operation would be preferable. (JD did indicate that overall, he prefers the manual cleaning).

LAKE PALESTINE ASSET INVENTORY

APPENDIX B

APPENDIX C

C, Exhibit 4.1

DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903) 939-8716.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2019 to December 31, 2019.

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report: You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791.

En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903) 531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eight miles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer. Tyler’s wells are currently categorized as inactive, but would be available in an emergency.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800) 426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903) 939-8716. TCEQ completed an assessment of your source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for your water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903) 939-8716.

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables.

DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

Contaminant - Any physical, chemical, biological or radiological substance or matter in water. The presence of contaminants does not necessarily indicate that the water poses a health risk.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

ND – Indicates that the parameter tested below the detection limit

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

Parameter - a particular chemical, combination of chemicals or microbiological entity that can be assigned a value: commonly a concentration, but may also be a logical entity (present or absent)

pCi/l (Picocuries per liter) - A measure of radioactivity.

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb.

ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a parameter in drinking water.

umho/cm - A unit of measurement for conductivity.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit.

CITY OF TYLER

DRINKING WATER QUALITY MONITORING ANALYSIS

January 1, 2020 to December 31, 2020

Regulated at the Customer’s Tap

The City of Tyler’s last Lead and Copper Rule sampling was in 2020. The results for the 2020 lead and copper sampling indicated that our water system is below the action limit for lead and copper.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.

* TTHMs – Some people who drink water containing TTHMs in excess of the MCL over many years may experience problems with their liver, kidneys, or central nervous systems and may have an increased risk of getting cancer.

Fecal coliform / E. coli Two Positive for 2020. All three repeats were Negative. MCL = A routine sample and a repeat sample are total coliform positive, and one is also fecal coliform or E. coli positive.

Fecal coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems. Two samples collected in 2020 tested positive for E. coli. Both sites were resampled within 24 hours and tested negative, indicating a probable contamination of the sample itself and not the water.

In the month of October, the MCL for Total Coliform Bacteria was exceeded. Sampling sites that tested positive were repeated and negative samples were obtained at all locations. This indicated probable contamination of the samples themselves due to improper sampling techniques, and not the water. The MCL exceedance triggered a Level 1 Assessment by TCEQ. The City of Tyler performed the Assessment and presented its findings to TCEQ. TCEQ accepted the City of Tyler’s Assessment and determined that no sanitary defects were identified in the City of Tyler’s Public Water System.

Measuring turbidity is required by state and federal law, and aids the City in determining the effectiveness of the clarification and filtration processes in removing particulate matter from drinking water. The City met all turbidity requirements in 2020.

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. Tyler has tested for cryptosporidium in both untreated and treated water. It has only been found in the untreated water supply, and has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit https://www.epa.gov/dwucmr/fourth-unregulated-contaminant-monitoring-rule, or call the Safe Water Hotline at (800-426-4791).

In the water loss audit submitted to the Texas Water Development Board for the time period of January through December 2020, our system lost an estimated

gallons of water. If you have any questions about the water loss audit please call 903-939-8716.

2019

DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903) 939-8716.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2019 to December 31, 2019

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report: You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791.

En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903)531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eight miles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer. Tyler’s wells are currently categorized as inactive, but would be available in an emergency.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800)426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903)939-8716 TCEQ completed an assessment of your source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for your water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903)939-8716

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables.

DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

Contaminant - Any physical, chemical, biological or radiological substance or matter in water. The presence of contaminants does not necessarily indicate that the water poses a health risk.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

ND – Indicates that the parameter tested below the detection limit.

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

Parameter - a particular chemical, combination of chemicals or microbiological entity that can be assigned a value: commonly a concentration, but may also be a logical entity (present or absent)

pCi/l (Picocuries per liter) - A measure of radioactivity

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb.

ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a parameter in drinking water.

umho/cm - A unit of measurement for conductivity.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit.

CITY OF TYLER

DRINKING WATER QUALITY MONITORING ANALYSIS

January 1, 2019 to December 31, 2019

Regulated at the Customer’s Tap

The City of Tyler’s last Lead and Copper Rule sampling was in 2019. The results for the 2019 lead and copper sampling indicated that our water system is below the action limit for lead and copper.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.

* TTHMs – Some people who drink water containing TTHMs in excess of the MCL over many years may experience problems with their liver, kidneys,

may have an increased risk of getting cancer.

central

systems

and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems.

turbidity is required by state and federal law, and aids the City in determining the effectiveness of the clarification and filtration processes in removing

matter from drinking water. The City met all turbidity requirements in 2019

Regulated at Treatment Plant and Wells

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. Tyler has tested for cryptosporidium in both untreated and treated water. It has only been found in the untreated water supply, and has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit https://www.epa.gov/dwucmr/fourth-unregulated-contaminant-monitoring-rule, or call the Safe Water Hotline at (800-426-4791).

In the water loss audit submitted to the Texas Water Development Board for the time period of January through December 2019, our system lost an estimated

gallons of water. If you have any questions about the water loss audit please call 903-939-8716.

2018

DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903) 939-8716.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2018 to December 31, 2018

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report: You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791.

En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903)531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eightmiles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800)426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903)939-8716 TCEQ completed an assessment of your source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for your water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903)939-8716

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables.

DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

Contaminant - Any physical, chemical, biological or radiological substance or matter in water.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

pCi/l (Picocuries per liter) - A measure of radioactivity

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb.

ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a contaminant in drinking water.

umho/cm - A unit of measurement for conductivity.

90th Percentile - The value determined by ranking and numbering sample results from highest to lowest (lowest = 1), multiplying the total number of samples by 0.90 (90%), and determining the sample result at the calculated ranking. Example: If 30 samples are collected, the 90th percentile would be the 27th highest sample result.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit. ND – Indicates that constituent tested below the detection limit.

DRINKING

CITY OF TYLER

WATER QUALITY MONITORING ANALYSIS

January 1, 2018 to December 31, 2018

Regulated at the Customer’s Tap

The City of Tyler’s last Lead and Copper Rule sampling was in 2018 The results for the 2018 lead and copper sampling indicated that our water system is below the action limit for lead and copper.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.

*

– Some people who drink water containing TTHMs

may have an increased risk of getting cancer.

excess of the MCL over many years may experience problems

coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems.

turbidity is required by state and federal law, and aids the City in determining the effectiveness of the clarification and filtration processes in removing

from drinking water. The City met all turbidity requirements in 2018

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. During 2018, Tyler tested for cryptosporidium in both untreated and treated water. It has only been found in the untreated water supply. Cryptosporidium has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit https://www.epa.gov/dwucmr/fourth-unregulated-contaminant-monitoring-rule, or call the Safe Water Hotline at (800-426-4791).

In the water loss audit submitted to the Texas Water Development Board for the time period of January through December 2018, our system lost an estimated

gallons of water. If you have any questions about the water loss audit please call 903-939-8716.

2017

DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903) 939-8716.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2017 to December 31, 2017

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report:

You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791.

En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903)531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eightmiles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800)426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903)939-8716 TCEQ completed an assessment of your source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for your water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903)939-8716

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables. DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

Contaminant - Any physical, chemical, biological or radiological substance or matter in water.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

Level 1 Assessment

A Level 1 assessment is a study of the water system to identify potential problems and determine (if possible) why total coliform bacteria were found.

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

pCi/L (Picocuries per liter) - A measure of radioactivity

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb. ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a contaminant in drinking water.

umho/cm - A unit of measurement for conductivity.

90th Percentile - The value determined by ranking and numbering sample results from highest to lowest (lowest = 1), multiplying the total number of samples by 0.90 (90%), and determining the sample result at the calculated ranking. Example: If 30 samples are collected, the 90th percentile would be the 27th highest sample result.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit. ND – Indicates that constituent tested below the detection limit.

The City of Tyler’s last Lead and Copper Rule sampling was in 2017. The results for the 2017 lead and copper sampling indicated that our water system is below the action limit for lead and copper.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.

* TTHMs

central nervous systems and may have an increased risk of getting cancer.

Some people who drink water containing TTHMs in excess of the MCL over many years may experience problems with their liver, kidneys,

No Positive for 2017

Fecal coliform / E. coli

MCL = A routine sample and a repeat sample are total coliform positive, and one is also fecal coliform or E. coli positive.

Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially harmful, waterborne pathogens may be present or that a potential pathway exists through which contamination may enter the drinking water distribution system. We found coliforms indicating the need to look for potential problems in water treatment or distribution. When this occurs, we are required to conduct assessment(s) to identify problems and to correct any problems that were found during these assessments. During the past year we were required to conduct one (1) Level 1 assessment. One (1) Level 1 assessment was completed. In addition, we were required to take one corrective action and we completed one corrective action.

Measuring turbidity is required by state and federal law, and aids the City in determining the effectiveness of the clarification and filtration processes in removing particulate matter from drinking water. The City met all TCEQ and EPA turbidity requirements in 2017

Cryptosporidium

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. During 2017, Tyler tested for cryptosporidium in both untreated and treated water. It has only been found in the untreated water supply. Cryptosporidium has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit http://www.epa.gov/safewater/ucmr/ucmr2/index.html, or call the Safe Water Hotline at (800-426-4791).

2016

DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903)939-8716.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2016 to December 31, 2016

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report: You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791. En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903)531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eight miles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800)426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903)939-8716 TCEQ completed an assessment of our source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for our water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903)939-8716

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables. DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow. Contaminant - Any physical, chemical, biological or radiological substance or matter in water.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

LRAA (Locational Running Annual Average) – Average of current sample result combined with the three previous sample results for an individual location

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

pCi/l (Picocuries per liter) - A measure of radioactivity

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb. ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a contaminant in drinking water.

umho/cm - A unit of measurement for conductivity.

90th Percentile - The value determined by ranking and numbering sample results from highest to lowest (lowest = 1), multiplying the total number of samples by 0.90 (90%), and determining the sample result at the calculated ranking. Example: If 30 samples are collected, the 90th percentile would be the 27th highest sample result.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit. ND – Indicates that constituent tested below the detection limit

The City of Tyler Water Utilities last sampled for Lead and Copper in 2016. Results for the 2016 lead and copper sampling indicate that our water system is below the action limit for lead and copper.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline (1-800-426-4791) or at http://www.epa.gov/safewater/lead.

* TTHMs – Some people who drink water containing TTHMs in excess of the MCL over many years may experience problems with their liver, kidneys, or central nervous systems and may have an increased risk of getting cancer. The City of Tyler received Notices of Violation for exceeding the maximum contaminant level for THM in 1st quarter and HAA5 in 1st and 2nd quarters of 2016.

Fecal coliform / E. coli No positives for 2016 MCL = 5% of routine monthly samples are positive for total coliform bacteria or a routine sample and a repeat sample are total coliform positive and one is also fecal coliform or E. coli positive.

Fecal coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems.

Regulated at the Treatment Plant

Turbidity is the cloudiness of the water caused by suspended particles. We monitor turbidity because it is a good indicator of the effectiveness of our settling and filtration processes. All TCEQ and EPA turbidity requirements were met in 2016.

Regulated at Treatment Plant and Wells

Cryptosporidium

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. During 2016, Tyler tested for cryptosporidium in both untreated and treated water. Cryptosporidium has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit http://www.epa.gov/safewater/ucmr/ucmr2/index.html, or call the Safe Water Hotline at (800-426-4791).

2015 DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903)531-1085.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2015 to December 31, 2015

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report: You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791. En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903)531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eight miles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800)426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903)939-8716 TCEQ completed an assessment of your source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for your water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903)939-8716

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables. DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow. Contaminant - Any physical, chemical, biological or radiological substance or matter in water.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

pCi/l (Picocuries per liter) - A measure of radioactivity

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb.

ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a contaminant in drinking water.

umho/cm - A unit of measurement for conductivity.

90th Percentile - The value determined by ranking and numbering sample results from highest to lowest (lowest = 1), multiplying the total number of samples by 0.90 (90%), and determining the sample result at the calculated ranking. Example: If 30 samples are collected, the 90th percentile would be the 27th highest sample result.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit. ND – Indicates that constituent tested below the detection limit

DRINKING

CITY OF TYLER

WATER QUALITY MONITORING ANALYSIS

January 1, 2015 to December 31, 2015

The City of Tyler received a “Notice of Violation” in 2014 and was required to submit “Public Notice” in January 2015 for failure to take lead and copper samples in 2014. In 2012, the TCEQ reduced the City of Tyler’s monitoring frequency for Lead and Copper from triennial to annual. Prior to 2012, the City of Tyler has triennially sampled for Lead and Copper at representative locations in our distribution system for decades with safe results. We last sampled for Lead and Copper in 2015. Samples results for the 2015 lead and copper sampling suite indicate that our water system is below the action limit for lead and is one tenth over the action limit for copper.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.

central nervous systems and may have an increased risk of getting cancer. The City of Tyler received Notices of Violation for exceeding the maximum contaminant level for HAA5s in the

– Some people who drink water containing TTHMs in excess of the MCL over many years may experience problems with their liver, kidneys,

coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems.

Regulated at the Treatment Plant

Measuring turbidity is required by state and federal law, and aids the City in determining the effectiveness of the clarification and filtration

Regulated at Treatment Plant and Wells

removing

matter from drinking water. The City met all turbidity requirements in 2010.

Cryptosporidium

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. During 2015, Tyler tested for cryptosporidium in both untreated and treated water. Cryptosporidium has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit http://www.epa.gov/safewater/ucmr/ucmr2/index.html, or call the Safe Water Hotline at (800-426-4791).

2014

DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903)939-8716.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2014 to December 31, 2014

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report: You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791.

En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903)531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eight miles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800)426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903)939-8716 TCEQ completed an assessment of your source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for your water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903)939-8716

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables.

DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

Contaminant - Any physical, chemical, biological or radiological substance or matter in water.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

pCi/l (Picocuries per liter) - A measure of radioactivity

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb.

ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a contaminant in drinking water.

umho/cm - A unit of measurement for conductivity.

90th Percentile - The value determined by ranking and numbering sample results from highest to lowest (lowest = 1), multiplying the total number of samples by 0.90 (90%), and determining the sample result at the calculated ranking. Example: If 30 samples are collected, the 90th percentile would be the 27th highest sample result.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit.

CITY OF TYLER DRINKING WATER QUALITY MONITORING ANALYSIS

January 1, 2014 to December 31, 2014

The City of Tyler received a “Notice of Violation” in 2014 and was required to submit “Public Notice” in January 2015 for failure to take lead and copper samples in 2014. In 2012, the TCEQ reduced the City of Tyler’s monitoring frequency for Lead and Copper from triennial to annual. Prior to 2012, the City of Tyler has triennially sampled for Lead and Copper at representative locations in our distribution system for decades with safe results. We last sampled for Lead and Copper in 2012. No health concerns are documented as evidenced in the 2012 lead and copper samples as listed above, and in this 2014 report. ’s last Lead and Copper Rule sampling was on September 12, 2012 Due to an excellent compliance history, the City’s sampling has been reduced to once every three (3) years. If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.

* TTHMs – Some people who drink water containing TTHMs in excess of the MCL over many years may experience problems with their liver, kidneys,

central nervous systems and may have an increased risk of getting cancer.

= A routine sample and a repeat sample

No

For 2014

total coliform positive, and one is also fecal coliform or E. coli positive. Fecal coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems.

Unregulated Initial Distribution System Evaluation – Disinfection Byproducts

This evaluation is sampling required by the EPA to determine the range of total trihalomethane and haloacetic acid in the system for future regulations. The samples are not used for compliance, and may have been collected under non-standard conditions. EPA also requires the data to be reported here.

Measuring turbidity is required by state and federal law, and aids the City in determining the effectiveness of the clarification and filtration processes in removing particulate matter from drinking water. The City met all turbidity requirements in 2010.

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. During 2008, Tyler tested for cryptosporidium in both untreated and treated water. Cryptosporidium has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit http://www.epa.gov/safewater/ucmr/ucmr2/index.html, or call the Safe Water Hotline at (800-426-4791)

2013

DRINKING WATER QUALITY REPORT

If you would like additional information concerning this report about the quality of your drinking water, please contact Tyler Water Utilities at (903)939-8716.

On September 18, 1998, the U.S. Environmental Protection Agency (EPA) adopted a rule requiring all water utilities to provide a detailed annual report informing its customers of the quality of their drinking water. Tyler Water Utilities is proud of our history of providing our customers with a safe and reliable supply of drinking water. In accordance with EPA requirements, the City of Tyler hereby provides this Annual Water Quality Report, which covers the period from January 1, 2013 to December 31, 2013

PUBLIC PARTICIPATION OPPORTUNITIES

The public may participate in City Council meetings held every second and fourth Wednesday at 9 a.m. involving water quality matters.

REQUIRED INFORMATION

The Texas Commission on Environmental Quality (TCEQ) requires that the following information be provided in this report: You may be more vulnerable than the general population to certain microbial contaminants, such as Cryptosporidium, in drinking water. Infants, some elderly, or immuno-compromised persons such as those undergoing chemotherapy for cancer; those who have undergone organ transplants; those who are undergoing treatment with steroids; and people with HIV/AIDS or other immune system disorders, can be particularly at risk from infections. You should seek advice about drinking water from your physician or health care provider. Additional guidelines on appropriate means to lessen the risk of infection by Cryptosporidium are available from the Safe Drinking Water Hotline at (800)426-4791.

En Espanol: Este reporte incluye informacion importante sobre el agua para tomar. Para asistancia en espanol, favor de llamar al telephono (903)531-1230.

SOURCES OF DRINKING WATER

Tyler Water Utilities receives raw surface water from two major sources. Raw water from Lake Tyler and Lake Tyler East, located approximately eight miles southeast of Tyler, is pumped to Golden Road Water Treatment Plant. Raw water from Lake Palestine, located approximately ten miles southwest of Tyler, is pumped to Lake Palestine Water Treatment Plant. At the treatment plants, raw water is treated, filtered, and disinfected before distribution. Tyler's water distribution system is also supplemented by eleven deep wells tapping the Carrizo-Wilcox aquifer.

ADDITIONAL INFORMATION

To ensure tap water is safe to drink, EPA prescribes regulations which limit the amount of certain contaminants in water provided by public water systems. FDA regulations establish limits for contaminants in bottled water which must provide the same protection for public health. Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency's Safe Drinking Water Hotline at (800)426-4791. Contaminants may be found in drinking water that may cause taste, color, or odor problems. These problems are not necessarily cause for health concern. For more information on taste, odor, or color of drinking water, please contact Tyler Water Utilities at (903)939-8716 TCEQ completed an assessment of your source water and results indicate that some of our sources are susceptible to certain contaminants. The sampling requirements for your water system are based on this susceptibility and previous sample data. Any detection of these contaminants will be found in this water quality report. For more information on source water assessments and protection efforts at our system, call (903)939-8716

WATER QUALITY RESULTS

The following tables provide the water quality results of Tyler's drinking water. Please note that a list of definitions has been provided to help you understand the tables.

DEFINITIONS

AL (Action Level) - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

Contaminant - Any physical, chemical, biological or radiological substance or matter in water.

HRA Avg. (Highest Running Annual Average) - The highest of four (4) values calculated by averaging each quarter’s average result with the previous three (3) quarter’s average results.

LMPS (Lowest Monthly Percentage of Samples) - The lowest of the monthly percentage of samples that meets the turbidity limit of <0.3 NTU.

MCL (Maximum Contaminant Level) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology.

MCLG (Maximum Contaminant Level Goal) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

N/A - Not Applicable

NTU (Nephelometric Turbidity Unit) - A unit of turbidity determined by measuring the side scattering of light caused by particulate matter.

pCi/l (Picocuries per liter) - A measure of radioactivity

ppb (Parts per Billion) - In drinking water, one atom or molecule of a substance in one billion molecules of water. Example: One cent in 10 million dollars equals one ppb.

ppm (Parts per Million) - In drinking water, one atom or molecule of a substance in one million molecules of water. Example: One cent in 10 thousand dollars equals one ppm.

TT (Treatment Technique) - A required process intended to reduce the level of a contaminant in drinking water.

umho/cm - A unit of measurement for conductivity.

90th Percentile - The value determined by ranking and numbering sample results from highest to lowest (lowest = 1), multiplying the total number of samples by 0.90 (90%), and determining the sample result at the calculated ranking. Example: If 30 samples are collected, the 90th percentile would be the 27th highest sample result.

< (less than sign) - The sign indicating the value was 'less than' or not detected at the detection limit of the analytical method or 'less than' the regulatory limit.

CITY OF TYLER DRINKING WATER QUALITY MONITORING ANALYSIS

January 1, 2013 to December 31, 2013

The City of Tyler’s last Lead and Copper Rule sampling was on September 12, 2012. Due to an excellent compliance history, the City’s sampling has been reduced to once every three (3) years.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. This water supply is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead.

* TTHMs – Some people who drink water containing TTHMs in excess of the MCL over many years may experience problems with their liver, kidneys,

central nervous systems and may have an increased risk of getting cancer.

No

For 2013

= A routine sample and a repeat sample are total coliform positive, and one is also fecal coliform or E. coli positive. Fecal coliforms and E. coli are bacteria whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term effects, such as diarrhea, cramps, nausea, headaches, or other symptoms. They may pose a special health risk for infants, young children, and people with severely compromised immune systems.

Unregulated Initial Distribution System Evaluation – Disinfection Byproducts

This evaluation is sampling required by the EPA to determine the range of total trihalomethane and haloacetic acid in the system for future regulations. The samples are not used for compliance, and may have been collected under non-standard conditions. EPA also requires the data to be reported here.

Measuring turbidity is required by state and federal law, and aids the City in determining the effectiveness of the clarification and filtration processes in removing particulate matter from drinking water. The City met all turbidity requirements in 2010.

Cryptosporidium is a tiny intestinal parasite found naturally in the environment. It is spread by human and animal waste. If ingested, cryptosporidium may cause cryptosporidiosis, an abdominal infection (symptoms include nausea, diarrhea, and abdominal cramps). Some of the ways cryptosporidium can be spread include drinking contaminated water, eating contaminated food that is raw or undercooked, exposure to the feces of animals or infected individuals (i.e. changing diapers without washing hands afterward), or exposure to contaminated surfaces. Not everyone exposed to the organism becomes ill. During 2008, Tyler tested for cryptosporidium in both untreated and treated water. Cryptosporidium has not been found in the Tyler treated drinking water. Tyler works to protect the watershed from contamination and optimizes the treatment process. Although Tyler’s water treatment process removes cryptosporidium, immuno-compromised persons should consult their physician regarding appropriate precautions to avoid infection.

Unregulated Parameters

Unregulated contaminants are those for which EPA has not established drinking water standards. The purpose of the unregulated contaminant monitoring is to assist EPA in determining the occurrence of unregulated contaminants in drinking water and whether future regulation is warranted. Any unregulated contaminants detected are reported in the following table. For additional information and data visit http://www.epa.gov/safewater/ucmr/ucmr2/index.html, or call the Safe Water Hotline at (800-426-4791)

APPENDIX D

290.41.(e)(4)

290.41.(e)(5)

An all weather road shall be provided to the raw water pump station.

The raw water pump station and all appurtenances must be installed in a lockable building that is designed to prevent intruder access or enclosed by an intruder-resistant fence with lockable gates.

Based on current acceptable design standards, the total capacity of the public water system's treatment facilities must always be greater than its anticipated maximum daily demand.

Access from McElroy Road

Chain link fence and gates at entrance to intake

Max day demand= 50.7 MGD

Average day demand= 20.3 MGD

Total capacity of the WTPs in Tyler= 34 MGD + 30 MGD = 64 MGD

§290.42. (a)(1)

§290.42. (a)(3)

Each water treatment plant shall be located at a site that is accessible by an all-weather road.

All water secured from surface sources shall be given complete treatment at a plant which provides facilities for pretreatment disinfection, taste and odor control, continuous coagulation, sedimentation, filtration, covered clear well storage, and terminal disinfection of the water with chlorine or suitable chlorine compounds. In all cases, the treatment process shall be designed to achieve at least a 2-log removal of Cryptosporidium oocysts, a 3-log removal or inactivation of Giardia cysts, and a 4-log removal or inactivation of viruses before the water is supplied to any consumer. The executive director may require additional levels of treatment in cases of poor source water quality. Based on raw water monitoring results, the executive director may require additional levels of treatment for Cryptosporidium treatment as specified in §290.111 of this title.

Access from Golden Road Y

Alum and chlorine are added for pretreatment disinfection, color and odor control. The treatment plant has a stage 1 and stage 2 rapid mix basin, 4 clariflocculator basin, 16 filtration units and 2 clear well tank. Chlorine is added for disinfection before filtration. No chemicals added at the intake.

Y

§290.42. (d)(1)

§290.42. (d)(8)(A)

Process

Mixing

Plants with a design capacity greater than 3.0 million gallons per day (MGD) must provide at least one hydraulic mixing unit or at least two sets of mechanical flash mixing equipment designed to operate in parallel. Public water systems with other surface water treatment plants, interconnections with other systems, or wells that can meet the system's average daily demand are exempt from the requirement for redundant mechanical flash mixing equipment.

Plants with a design capacity greater than 3.0 MGD must provide at least two sets of flocculation equipment which are designed to operate in parallel. Public water systems with other surface water treatment plants, interconnections with other systems, or wells that can meet the system's average daily demand are exempt from the requirement for redundant flocculation equipment.

Design Capacity of WTP= 34MGD. There are 2 mixer basins in GR WTP.

A) 1st stage- rapid mix basin with 2 mechanical mixers operated continuously

B) 2nd stage-rapid mix basin with 1 mechanical mixer operated when certain conditions apply Y

Design Capacity of WTP= 34MGD.

There are 4 clariflocculators in GR WTP. Clarifier #1, #2, #4 flocculators work off the same principle. All three of these clarifiers have mixing style flocculation devices and the sludge rack is at the bottom of the tank.

-Clarifier #3 has large flocculation arms that are attached at the top of the mechanism and protrude downward about 8 feet. The sludge rack also has arms that point upwards and mesh with the flocculator arms. The flocculators and sludge rack move in different directions and assist in forming floc.

From the recent site visit, it was noted that the flocculator motors in all 4 clarifiers are not functional.

§290.42. (d)(9)(A) Flocculator

Flocculation facilities for straight-flow and up-flow sedimentation basins shall provide a minimum theoretical detention time of at least 20 minutes when operated at their design capacity. Flocculation facilities constructed prior to October 1, 2000, are exempt from this requirement if the settled water turbidity of each sedimentation basin remains below 10.0 nephelometric turbidity units and the treatment plant meets with turbidity requirements of §290.111 of this title.

§290.42. (d)(9)(B)(i) Flocculator

§290.42. (d)(9)(C) Flocculator to Sedimentation

§290.42. (d)(10)(A) Clarification facilities

Coagulated water or water from flocculators shall flow to sedimentation basins in such a manner as to prevent destruction of floc. Piping, flumes, and troughs shall be designed to provide a flow velocity of 0.5 to 1.5 feet per second. Gates, ports, and valves shall be designed at a maximum flow velocity of 4.0 feet per second in the transfer of water between units

Plants with a design capacity greater than 3.0 MGD must provide at least two sedimentation basins or clarification units which are designed to operate in parallel.

When operated at their design capacity, basins for straight-flow or up-flow sedimentation of coagulated waters shall provide either a theoretical detention time of at least six hours in the flocculation and sedimentation chambers or a maximum surface overflow rate of 0.6 gpm/sq ft of surface area in the sedimentation chamber.

§290.42. (d)(10)(C)(i) Clarification facilities

§290.42. (d)(10)(C)(iv) Clarification facilities

A side wall water depth of at least 12 feet shall be provided in clarification basins that are not equipped with mechanical sludge removal facilities.

Y [Note: Flocculator motors not functional, recommended O&M fix]

Detention Time per basin is 2.9 hrs Y

Golden road water treatment plant has a clariflocculator basin. Flocculation occurs in the inner well. Water enters the outer clarification zone where the settleable particles settle at bottom of basin. Criteria not application NA

Design Capacity of WTP= 34MGD. The plant has 4 parallel clariflocculators Y

Computed Detention Time= 3.3 hrs

The clarifloculator basin is divided into two , 1) flocculation chamber (inner chamber) and 2) clarification zone (outer chamber)

Computed Overflow Rate (@ clarification zone)= 0.60 gpm/sq ft (TCEQ max 0.6 gpm/sq ft) Y

All four clariflocculator has sludge rack at the bottom of the tank per O&M manual. However, from site visit it was noted that parts of clariflocculators are rusted and deteriorated Y

§290.42. (d)(10)(C)(v) Clarification facilities The effective length of a straight-flow sedimentation basin shall be at least twice its effective width. Circular clarifloccuator NA

§290.42. (d)(10)(D)(i) Clarification facilities Facilities for sludge removal shall be provided by mechanical means or by hopper-bottomed basins with valves capable of complete draining of the units. All four clariflocculator has sludge rack at the bottom of the tank per O&M manual. However, from site visit it was noted that parts of clariflocculators are rusted and deteriorated Y

The design capacity of gravity rapid sand filters shall not exceed a maximum filtration rate of 2.0 gpm/sq ft. At the beginning of filter runs for declining rate filters, a maximum filtration rate of 3.0 gpm/sq ft is allowed.

GR WTP has 16 filters. Assuming 2 filter out of service, Filtration Rate= 3.19 gpm/sq ft.

§290.42. (d)(11)(B)(i)&(ii)

Filtration (Gravity Filters)

Where high-rate gravity filters are used, the design capacity shall not exceed a maximum filtration rate of 5.0 gpm/sq ft. At the beginning of filter runs for declining rate filters, a maximum filtration rate of 6.5 gpm/sq ft is allowed.

Any surface water treatment plant that provides, or is being designed to provide, 7.5 MGD or more must be able to meet either the maximum daily demand or the minimum required 0.6 gpm per connection, whichever is larger, with the largest filter off-line.

Meets TCEQ criteria of high rate gravity filter. Y

Total capacity of the WTPs in Tyler= 34 MGD + 30 MGD = 64 MGD

Max day demand= 50.7 MGD

§290.42. (d)(11)(B)(v)

WTP

Filtering Material

The depth of filter sand, anthracite, granular activated carbon, or other filtering materials shall be 24 inches or greater and provide an L/d ratio, as defined in §290.38 of this title (relating to Definitions), of at least 1,000.

L/d ratio--The dimensionless value that is obtained by dividing the length (depth) of a granular media filter bed by the weighted effective diameter "d" of the filter media. The weighted effective diameter of the media is calculated based on the percentage of the total bed depth contributed by each media layer.

For 34040 connections, Required treatment plant capacity= 29.4 MGD Y

Depth of filter material: 12-in Sand

24-in Anthracite which meets the min depth specified by TCEQ

The L/D ratio computed based on assumed size of the filter particle is 1219 which meets the TCEQ min criteria of 1000 Y

§290.42. (d)(11)(C)(iii)

§290.42. (d)(11)(C)(II) Filtering Material

(II) High-rate dual media filters typically contain a minimum of 12 inches of sand with an effective size of 0.45 to 0.55 mm and 24 inches of anthracite with an effective size of 0.9 to 1.1 mm. The uniformity coefficient of each material should not exceed 1.6.

Depth of filter material: 12-in Sand 24-in Anthracite. Uniformity coefficient 1.4 Y

§290.42. (d)(11)(C)(iv)

Filtering Material

§290.42. (d)(11)(F)(iii) Backwash

§290.42. (d)(11)(F)(iv)(I) Backwash

Under the filtering material, at least 12 inches of support gravel shall be placed varying in size from 1/16 inch to 2.5 inches. The gravel may be arranged in three to five layers such that each layer contains material about twice the size of the material above it. Other support material may be approved on an individual basis.

The rate of flow of backwash water shall not be less than 20 inches vertical rise per minute (12.5 gpm/sq ft) and usually not more than 35 inches vertical rise per minute (21.8 gpm/sq ft).

For facilities equipped with air scour, the backwash facilities shall be capable of expanding the filtering bed at least 15% during the backwash cycle.

12-in of Gravel support not shown in the 2019 record drawing. Underneath the filter media is the Filter make-up block.

Rate of backwash assuming 1 pump as standby = 20gpm/sq ft

Filter Bed Expansion > 15% based on assumed filter bed parameters

§290.42. (d)(11)(F)(v) Backwash The filter freeboard in inches shall exceed the wash rate in inches of vertical rise per minute. Freeboard > Vertical rise per min Y

Backwash Gravity filters installed after January 1, 1996, shall be equipped with air scour backwash or surface wash facilities.

Phase III Improvement submittal for GR WTP shows details of Drop Pipe Air Scour System

a) High Rate Backwash- 20 GPM/SQ FT

b) Air Flow Rate- 4 SCFM/SQ FT Y

§290.42. (d)(11)(F)(vii)

§290.42. (f)(1)(E)(ii) Chemical Storage Storage

Except as provided in this clause, adequate containment facilities shall be provided for all liquid chemical storage tanks.

(I) Containment facilities for a single container or for multiple interconnected containers must be large enough to hold the maximum amount of chemical that can be stored with a minimum freeboard of six vertical inches or to hold 110% of the total volume of the container(s), whichever is less.

(II) Common containment for multiple containers that are not interconnected must be large enough to hold the volume of the largest container with a minimum freeboard of six vertical inches or to hold 110% of the total volume of the container(s), whichever is less.

No containment facilities are required for hypochlorite solution containers that have a capacity of 55 gallons or less.

Fluoride, Alum. Ammonia tank are double contained

Volume of alum day tank = 500 gal

Volume of alum containment = 2007 gal

Volume of flouride day tank = 300 gal

Volume of flouride containment = 1316 gal

Volume of caustic day tank = 540 gal

Volume of caustic containment = 1245 gal

Volume of caustic bulk tank = 8700 gal

Volume of caustic containment = 26906 gal

§290.45(a)(6) WTP

§290.45(b)(2)(A) Community water systemSurface Water

§290.45(b)(2)(B)

The capacity of the treatment facilities shall not be less than the required raw water or groundwater production rate or the anticipated maximum daily demand of the system.

Surface water supplies must meet the following requirements:

(A) a raw water pump capacity of 0.6 gpm per connection with the largest pump out of service;

Community water systemSurface Water Surface water supplies must meet the following requirements:

§290.45(b)(2)(D) Community water systemSurface Water

(B) a treatment plant capacity of 0.6 gpm per connection under normal rated design flow;

Surface water supplies must meet the following requirements: (D) a covered clear well storage capacity at the treatment plant of 50 gallons per connection or, for systems serving more than 250 connections, 5.0% of daily plant capacity;

There are 3 raw water pumps at Lake Tyler Intake @ 18 MGD each

Max day demand= 50.7 MGD

Capacity of WTP =30+ 34= 64 MGD

Capacity of Raw Water Pump Station (1 pump stand by)= 30 +36=66 MGD

The 3 raw water pumps at Lake Tyler (feeds Golden Road WTP) are rated at 18 MGD each.

Assuming a 60/40 split between Lake Palestine WTP and Golden Road WTP

Required raw water pump capacity= 8170 gpm

Actual raw water pump capacity (with largest pump out of service)=25,000 gpm

Required treatment plant capacity= 11.8 mgd

Actual treatment plant capacity= 34 mgd

Required clear well storage capacity= 1.2 MG

Actual storage capacity of 1 tank=2.0 MG

There are 2 covered clear wells in Golden Road WTP.

290.41.(e)(4)

290.41.(e)(5)

An allweather road shallbe provided to the rawwater pump station.

The rawwater pump station and all appurtenances must be installed in a lockable building that is designed to prevent intruder access or enclosed by an intruder-resistant fence with lockable gates.

Based on current acceptable design standards, the total capacity of the public water system's treatment facilities must always be greater than its anticipated maximum daily demand.

Access from Road 2661

Chain link fence and gates at entrance to intake

Max day demand= 50.7 MGD

Average day demand= 20.3 MGD

Totalcapacity of the WTPs in Tyler= 34 MGD + 30 MGD = 64 MGD

§290.42. (a)(1)

§290.42. (a)(3)

Each water treatment plant shall be located at a site that is accessible by an all-weather road.

Allwater secured from surface sources shallbe given complete treatment at a plant which provides facilities for pretreatment disinfection, taste and odor control, continuous coagulation, sedimentation, filtration, covered clear wellstorage, and terminaldisinfection of the water with chlorine or suitable chlorine compounds. In allcases, the treatment process shallbe designed to achieve at least a 2-log removal of Cryptosporidium oocysts, a 3-log removal or inactivation of Giardia cysts, and a 4-log removal or inactivation of viruses before the water is supplied to any consumer. The executive director may require additional levels of treatment in cases of poor source water quality. Based on raw water monitoring results, the executive director may require additionallevels of treatment for Cryptosporidium treatment as specified in §290.111 of this title.

Access from Road 192

The treatment plant has ozone contact basin to treat taste and odor, one rapid mix basin with 3 parallel channels for chemicalmixing, Six flocculation units with 3 compartments in series, 3 sedimentation basins 8 filtration units and 2 clear welltank. Y

§290.42. (d)(1)Process

Mixing

§290.42. (d)(8)(A)

§290.42. (d)(9)(A)Flocculator

Plants with a design capacity greater than 3.0 million gallons per day (MGD) must provide at least one hydraulic mixing unit or at least two sets of mechanical flash mixing equipment designed to operate in parallel. Public water systems with other surface water treatment plants, interconnections with other systems, or wells that can meet the system's average daily demand are exempt from the requirement for redundant mechanicalflash mixing equipment.

Plants with a design capacity greater than 3.0 MGD must provide at least two sets of flocculation equipment which are designed to operate in parallel. Public water systems with other surface water treatment plants, interconnections with other systems, or wells that can meet the system's average daily demand are exempt from the requirement for redundant flocculation equipment.

Flocculation facilities for straight-flow and up-flow sedimentation basins shallprovide a minimum theoretical detention time of at least 20 minutes when operated at their design capacity. Flocculation facilities constructed prior to October 1, 2000, are exempt from this requirement if the settled water turbidity of each sedimentation basin remains below 10.0 nephelometric turbidity units and the treatment plant meets with turbidity requirements of §290.111 of this title.

Design Capacity of WTP= 30MGD. Rapid mix basin with 3 parallel channels for chemical mixing with combination of 2 mechanicalmixers and baffle walls in each parallelchamber Y

Design Capacity of WTP= 30MGD. Six flocculation units with 3 compartments in series

Detention Time per basin is 30 min.

§290.42. (d)(9)(B)(i)Flocculator

§290.42. (d)(9)(C) Flocculator to Sedimentation

§290.42. (d)(10)(A)Clarification facilities

§290.42. (d)(10)(C)(i)Clarification facilities

§290.42. (d)(10)(C)(iv)Clarification facilities

§290.42. (d)(10)(C)(v)Clarification facilities

§290.42. (d)(10)(D)(i)Clarification facilities

Coagulated water or water from flocculators shallflowto sedimentation basins in such a manner as to prevent destruction of floc. Piping, flumes, and troughs shallbe designed to provide a flowvelocity of 0.5 to 1.5 feet per second. Gates, ports, and valves shallbe designed at a maximum flowvelocity of 4.0 feet per second in the transfer of water between units

Plants with a design capacity greater than 3.0 MGD must provide at least two sedimentation basins or clarification units which are designed to operate in parallel.

When operated at their design capacity, basins for straight-flow or up-flowsedimentation of coagulated waters shallprovide either a theoretical detention time of at least six hours in the flocculation and sedimentation chambers or a maximum surface overflow rate of 0.6 gpm/sq ft of surface area in the sedimentation chamber.

A side wallwater depth of at least 12 feet shall be provided in clarification basins that are not equipped with mechanical sludge removal facilities.

The flow velocity in the 36-in and 48-in canal gate is in between 1.1-1.3 ft/sec.

Design Capacity of WTP= 30MGD. Rapid mix basin with 3 parallel sedimentation tanks

1) Computed Detention Time= 3.4 hrs (min 6 hrs) OR

2) Computed OverflowRate= 0.56 gpm/sq ft (TCEQ max 0.6 gpm/sq ft) Overflow rate satisfies TCEQ criteria

Trussed Rake Arms provided for sludge removal

The effective length of a straight-flow sedimentation basin shallbe at least twice its effective width.Length of sedimentation basin= 189

Width of sedimentation basin= 65

L:B= 3:1

Facilities for sludge removal shallbe provided by mechanicalmeans or by hopper-bottomed basins with valves capable of complete draining of the units. Trussed Rake Arms provided for sludge removal Y

The design capacity of gravity rapid sand filters shallnot exceed a maximum filtration rate of 2.0 gpm/sq ft. At the beginning of filter runs for declining rate filters, a maximum filtration rate of 3.0 gpm/sq ft is allowed. Where high-rate gravity filters are used, the design capacity shallnot exceed a maximum filtration rate of 5.0 gpm/sq ft. At the beginning of filter runs for declining rate filters, a maximum filtration rate of 6.5 gpm/sq ft is allowed.

Assuming 1 filter out of service, Filtration Rate= 4.96 gpm/sq ft.

Meets TCEQ criteria of high rate gravity filter. Y

§290.42. (d)(11)(B)(i)&(ii)Filtration (Gravity Filters)

Any surface water treatment plant that provides, or is being designed to provide, 7.5 MGD or more must be able to meet either the maximum daily demand or the minimum required 0.6 gpm per connection, whichever is larger, with the largest filter off-line.

Totalcapacity of the WTPs in Tyler= 34 MGD + 30 MGD = 64 MGD

Max day demand= 50.7 MGD

For 34040 connections, Required treatment plant capacity= 29.4 MGD Y

§290.42. (d)(11)(B)(v)WTP

The depth of filter sand, anthracite, granular activated carbon, or other filtering materials shall be 24 inches or greater and provide an L/d ratio, as defined in §290.38 of this title (relating to Definitions), of at least 1,000.

L/d ratio--The dimensionless value that is obtained by dividing the length (depth) of a granular media filter bed by the weighted effective diameter "d" of the filter media. The weighted effective diameter of the media is calculated based on the percentage of the total bed depth contributed by each media layer.

Depth of filter material: 12-in Sand

24-in Anthracite which meets the min depth specified by TCEQ .

The L/D ratio computed based on assumed size of the filter particle is 1355 which meets the TCEQ min criteria of 1000 Y

§290.42.

(d)(11)(C)(iii)Filtering Material

§290.42. (d)(11)(C)(II)Filtering Material

§290.42. (d)(11)(C)(iv)Filtering Material

§290.42. (d)(11)(F)(iii)Backwash

§290.42. (d)(11)(F)(iv)(I)Backwash

(II) High-rate dualmedia filters typicallycontain a minimum of 12 inches of sand with an effective size of 0.45 to 0.55 mm and 24 inches of anthracite with an effective size of 0.9 to 1.1 mm. The uniformitycoefficient of each materialshould not exceed 1.6.

Under the filtering material, at least 12 inches of support gravelshallbe placed varying in size from 1/16 inch to 2.5 inches. The gravelmaybe arranged in three to five layers such that each layer contains materialabout twice the size of the materialabove it. Other support materialmaybe approved on an individualbasis.

The rate of flowof backwash water shallnot be less than 20 inches verticalrise per minute (12.5 gpm/sq ft) and usuallynot more than 35 inches vertical rise per minute (21.8 gpm/sq ft).

For facilities equipped with air scour, the backwash facilities shallbe capable of expanding the filtering bed at least 15% during the backwash cycle.

§290.42. (d)(11)(F)(v)Backwash The filter freeboard in inches shallexceed the wash rate in inches of verticalrise per minute.

Gravityfilters installed after January1, 1996, shallbe equipped with air scour backwash or surface wash facilities.

Depth of filter material: 12-in Sand 24-inAnthracite. Uniformitycoefficient unknown

12-in of Gravelsupport not shown in the record drawing. Underneath the filter media is the Filter make-up block. MaterialUnknown

Rate of backwash assuming 1 pump as standby= 20gpm/sq ft

Filter Bed Expansion > 15% based on assumed filter bed parameters

Freeboard > Verticalrise per min

The Filter designed for the following flowrates per record dwg in March 2000 (sheet 76/23)

a) High Rate Backwash- 20 GPM/SQ FT

b) Air Scour- 4 SCFM/SQ FT

c) Concurrent Air/Water - 4 SCFM/5 GPM /SQ FT

Y

Y

Y

§290.42. (d)(11)(F)(vii)Backwash

Except as provided in this clause, adequate containment facilities shallbe provided for allliquid chemicalstorage tanks.

(I) Containment facilities for a single container or for multiple interconnected containers must be large enough to hold the maximum amount of chemical that can be stored with a minimum freeboard of six verticalinches or to hold 110% of the totalvolume of the container(s), whichever is less.

Volume of alum tank #1& 2 = 12,000 gal

Volume of alum containment = 18,949 gal

Volume of alum tank #3 = 1450 gal

§290.42. (f)(1)(E)(ii)

Chemical Storage Storage

(II) Common containment for multiple containers that are not interconnected must be large enough to hold the volume of the largest container with a minimum freeboard of six verticalinches or to hold 110% of the totalvolume of the container(s), whichever is less.

Nocontainment facilities are required for hypochlorite solution containers that have a capacityof 55 gallons or less.

Volume of alum containment = 498 gal

Volume of newfluoride bulk storage tank = 5400 gal

Volume of fluoride containment = 10,240 gal

Volume of fluoride daytank = 250 gal

Volume of fluoride containment = 592 gal

Volume of old fluoride bulk storage tank = 6000 gal

Volume of fluoride containment = 7659 gal

§290.45(a)(6)WTP

§290.45(b)(2)(A) Communitywater systemSurface Water

§290.45(b)(2)(B) Communitywater systemSurface Water

§290.45(b)(2)(D) Communitywater systemSurface Water

The capacityof the treatment facilities shallnot be less than the required rawwater or groundwater production rate or the anticipated maximum daily demand of the system.

Surface water supplies must meet the following requirements:

(A) a rawwater pump capacityof 0.6 gpm per connection with the largest pump out of service;

Surface water supplies must meet the following requirements: (B) a treatment plant capacityof 0.6 gpm per connection under normalrated design flow;

Surface water supplies must meet the following requirements: (D) a covered clear wellstorage capacityat the treatment plant of 50 gallons per connection or, for systems serving more than 250 connections, 5.0% of dailyplant capacity;

There are 3 rawwater pumps at Lake Palestine Intake @ 15 MGD each

Max daydemand= 50.7 MGD

Capacityof WTP=30+ 34= 64 MGD

Capacityof RawWater Pump Station (1 pump stand by)= 30 +36=66 MGD

The 3 rawwater pumps at Lake Palestine (feeds Lake Palestine WTP) are rated at 15 MGD each.

Assuming a 60/40 split between Lake Palestine WTPand Golden Road WTP

Required rawwater pump capacity= 12254.4 gpm

Actual Rawwater pump capacity(with largest pump out of service)=20833.2 gpm

Required treatment plant capacity= 17.6 mgd

Actualtreatment plant capacity= 30 mgd

Required clear wellstorage capacity= 1.5 MG

Actualstorage capacityof 1 tank=1.99 MG

There are 2 covered clear wells in Lake Palestine WTP.

APPENDIX E

Sources

The study conducted by Watson et al. (2008) on 59 WTPs in the Great Lakes region found that significant number (20%) of utilities report T&O events. Cyanobacteria, also known as blue-green algae, naturally occur within marine and fresh water ecosystems. Few species of cyanobacteria as shown in Table E.1 are responsible for the production of compounds such as geosmin (trans‐1,10‐dimethyl‐trans‐9‐decalol) and 2‐methylisoborneol (MIB) as well as cyanotoxins.

Geosmin and MIB which produce earthy and musty scents, respectively, cause widespread T&O problems in drinking water (Lanciotti et al., 2003; Ma et al., 2013; Watson et al., 2008; Westerhoff et al., 2005). Cyanobacteria release the compounds geosmin and MIB depending on the stage of growth and environmental variables. Typically, these odorants are released during death and biodegradation of these cells. Several studies have attempted to understand the factors triggering the formations of MIB and geosmin. The factors reported from the study conducted by Wood et al. (1983) are elevated nutrient levels in water, aerobic conditions, and accumulation of sediment in the reservoir. A recent study by Clercin, N. A., & Druschel, G. K. (2019) in Eagle Creek reservoir, Indianapolis revealed that high stream discharges bringing in nutrients and mixing the reservoir water columns are favorable conditions to support the growth of cyanobacteria that synthesis MIB and geosmin. Zhamg et al, 2009 reported cool temperatures and low light as factors that stimulated the geosmin production in cyanobacteria.

Cyanotoxins can be located within the intact cyanobacteria cell termed as intracellular. The release of these cyanotoxins in an algal bloom into the surrounding water occurs mostly during cell death and lysis . However, some cyanobacteria species (extracellular) are capable of releasing cyanotoxins into the water without cell rupture or death.

APPENDIXE Part 6.2

HealthEffects

Recent studies have highlighted the co-occurrence of MIB and geosmin with other cyanotoxins. In the study conducted by Graham et al, in 2010, microcystin co-occurred with geosmin in 87% of blooms and with MIB in 39%. Anatoxin-a co-occurred with geosmin in 100% of blooms, with MIB in 43%. Although cyanotoxins and T&O frequently co-occurred, concentrations were not strongly correlated. The study conducted by USGS 2021 in 23 midwest lakes revealed that cyanotoxins and taste and odor compounds co-occurred in 91% of the samples. Additionally, multiple toxin classes co-occurred in 48% of the samples. This is why it is important for to monitor cyanotoxin and to ensure that the cyanotoxins levels are below the threshold during a T&O outbreak.

Per the 2016 EPA report, treatment adjustments for cyanotoxins depends on the monitoring results and type of cyanotoxins present (e.g., microcystins, cylindrospermopsin, or others). If cyanotoxins are present, it is helpful to understand if they are located within the cyanobacteria cell (intracellular) or outside the cell within the water matrix (extracellular) to implement any treatment strategies. Thus, identifying the nature and type of cyanobacteria and cyanotoxins are present in their water helps in adopting an appropriate T&O treatment process. Detection and treatment of cyanotoxins are beyond the scope of this study.

Section A: Additionalinformation on PowderedActivatedCarbon

The efficiency of PAC depends primarily on the carbon type (pore size), dosage, contact time, location of application, and presence of natural organic matter. Mesoporous carbon (such as wood-based PAC) has been found to be the most effective at removing microcystins and cylindrospermopsin (WHO, 1999; U.S. EPA, 2014a; Sklenar et al., 2014; Westrick et al., 2010; Drikas et al., 2002). For cyanotoxin removal, a PAC dose of more than 20 mg/L would be necessary, which is greater than what is generally used in drinking water treatment (Jurczak et al., 2005; Tokodi et al., 2012; U.S. EPA, 2014a). PAC dosage depends on type and concentration of organic compounds present. For nominal taste and odor control typical dosages range between 2 to 20 ng/L. However, dosage can go as high as 100 ng/L to handle severe taste and odor episodes (WTP design, AWWA 1969). Because multiple factors play into removal efficiency with PAC, it is recommended that jar testing be conducted to determine optimal dose and PAC type (EPA, 2016).

PAC should not be added concurrently with chlorine or potassium permanganate because PAC will adsorb these chemicals. (WTP design, AWWA 1969). Surface of PAC particles should not be coated with coagulants or other or other water treatment chemicals before PAC has adequate contact time with the source water (WTP design, AWWA 1969). The study on Shenango Water Treatment Plant (Mott MacDonald, 2014) found that, dosing PAC with alum resulted in significantly lower MIB removal than dosing PAC prior to alum (29% vs. 54%) by conducted PAC jar test.

Presence of organic matter in raw water negatively affects the ability of activated carbon to remove geosmin and MIB. Natural organic matter (NOM) and dissolved organic carbon (DOC) competes for adsorption sites on the activated carbon (Bruce et al., 2002, Cook et al. on 2001, 2004). Alkalinity, hardness, and pH do not appear to affect the adsorption of MIB and geosmin over the ranges generally encountered in drinking water treatment. Therefore, changes to these water quality parameters will not affect the PAC doses required for taste and odor removal

TableE.1: Advantagesand Disadvantagesof Different PACApplication Points (Source: AWWA, (1990), “WTP Design”)

Point of addition

Intake

Slurry contractor preceding rapid mix

Advantage

Long contact time, good mixing

Excellent mixing for the design contact time, no interference by coagulants, additional contact time possible during flocculation and sedimentation

Disadvantage

Some substance may adsorb that otherwise would be removed by coagulation, thus increasing the activated carbon usage rate

A new basin and mixer may have to be installed; some competition may occur from molecules that otherwise would be removed by coagulants

Rapid mix

Good mixing during rapid mix and flocculation, reasonable contact time

Filterinlet Efficient use of PAC

Possible reduction in rate of adsorption because of interference by coagulants, contact time may be too short for equilibrium to be reached for some contaminants, some competition may occur from molecules that otherwise would be removed by coagulation

Possible loss of PAC through the filters and into the distribution system

TableE.2: Summaryof Researchon Geosmin/MIB Treatment using PAC

Coal and wood based PAC

Lower removal rates occurred at shorter contact times and lower PAC dosages

Geosmin removal increased approx 20% when contact time was increased from 15 to 70 minutes

Section B: Additionalinformation on BiologicalTreatment

TableE.3: Summaryof Research on Geosmin /MIB Treatment using BiologicalMethods

Mechanism:OzoneremovespartofgeosminandMIB,butitalsogeneratesbyproductsthataremorebiodegradable.Followingozonation,biofiltration hasthepotentialtoreducetheconcentrationofthesehighlydegradableozonationby-productsdramatically.Thisbiodegradationincreasesthebiomass inthefilter,whichshouldhelptheresidualgeosminandMIBdegradefaster.

ThebenchstudyconductedbyElhadi(2006)demonstratedthatozonationfollowedbybiofiltrationinMIB/geosminremovalwiththebestremovalinGAC mediaat20oC.For atargetinfluentconcentrationof100ng/L,60%geominremovalwas achieved.Thefactors affectingtheremoval(↑) werenotedas temperature(↑),mediatype,influentconcentrations .

ThefollowingschematicillustratesthetreatmenttraininCentralLakeCountyJointActionWaterAssociation(CLC-JAWA)plant(37.5mgd)inLakeBluff, IllinoisincompactingMIB/geosminusingozonationfollowedbybiologicallyactivegranularactivatedcarbon.(RobertNerenberg(2000))

Mechanism:Thepurposeofbiologicalpretreatmentistomakeuseofbiodegradableorganiccarbonandnutrientsthatwouldotherwisebeeliminated duringconventionaltreatment.ThestudyconductedbyBrownJ,NyfenneggerJ,AngY,etal.,2020revealedthatrapidratebiologicalroughingfiltration (>2gpm/ft2)caneffectivelytreatavaryingrangeofrawwatergesominlevelsusingshortcontacttimes.Temperatureandintermittentodorantpresence didnotimpactoperationoftheunit.Basedonthepilot-scaleanalysis,for99percentileremovalof564ng/Lgesomin,therequiredflterEBCTwas10 min.Upgradingtheunitfrom3to10minEBCTincreasedthecostby150%.ThefollowingschematicillustratesthetreatmenttrainforManateeCounty WTP,Florida(54mgd).TheBRFreducedgeosmintobelowthe7ng/Ltarget.However,onJune8,PACwasusedincombiantionwithBRFtoreduce peakgeosminconcentrationsof138ng/L

ThestudyconductedbyNerenbergetal.,2000repotedMIBremovalof93-100%foraninfluentMIBconcentrationof40ng/Lusingozonationplus biofiltration.

Section C: Additionalinformation on Ozone

Many taste and odor compounds, including geosmin and MIB, have been found to be effectively treated by ozone (Atasi et al., 1999; Ho et al., 2002; 2004). Geosmin is oxidized more rapidly than MIB. About 50% to 60% removal of MIB is expected at normal disinfection dosages (+10% for geosmin) Coffey 2000; Nerenberg et al; 2000). In a pilot plant study comparing the MIB/geosmin removal efficiencies of various oxidants (Cl2, ClO2, O3), 3.8mg/L ozone showed 85% removal of MIB/geosmin at a contact time of 6.4 min (Jung et al., 2004). Ozonation alone operated at disinfection dosage has eliminated taste and odor complaints at WTP including plants located in California Texas, Illinois, Ontario (Canada), Pennsylvania, Wisconsin and New Jersey. The raw water MIB and geosmin concentration in these plants were generally <50 ng/L. Due to the resistance of tertiary alcohols to oxidative treatments, higher doses of ozone are required to treat geosmin/MIB when compared to other T&O compounds and disinfection (Lalezary et al. 1986, ASU, 2002).

TableE.4: Summaryof ResearchonGeosmin/MIB Treatmentusing Ozone

Section D: Additionalinformation on Ozone+HydrogenPeroxide

Ozone is a selective oxidant; some organic and inorganic compounds are oxidized quickly and others are not oxidized at all whereas hydroxyl radical are not selective and can oxidize organic and inorganic compounds. In ozone based AOP, ozone is purposefully decomposed into hydroxyl .

AOPMechanism

Ozone follows two mechanisms while entering a solution: direct oxidation and auto decomposition into hydroxyl ions. Direct oxidation is relatively a slow and selective process. The presence of hydroxyl radicals, organic radicals, hydrogen peroxide, UV light, or a high concentration of hydrogen ion catalyzes auto decomposition to hydroxyl radical. The products of auto decomposition, hydroxyl radical and organic radical act as chain carriers and accelerate the auto decomposition process.

Hydrogen peroxide, H2O2 is used in conjunction with ozone O3 to enhance the formation of hydroxyl radicals in an O3/H2O2 AOP. The following equation illustrates mechanism of AOP.

H2O2 + H2O → HO2- +H3O+

O3 + HO2- →. OH + O2-+ O2

The ratio of hydrogen peroxide to ozone is variable to achieve desired hydroxyl ion exposure, because water quality parameters (temperature, pH, alkalinity, DOC) affect production rate of hydroxyl ions. The factors affecting geosmin/MIB removal efficiency in an ozone+hydrogen peroxide AOP process is illustrated in Table E.5.

The relationship between hydroxyl ion exposure and ozone exposure can be established using the RCT value. RCT value is directly proportional to hydroxyl ion exposure which means that for a given condition hydroxyl ion exposure increases as RCT value increases. RCT value increases with increasing temperature, pH increasing NOM and decreasing carbonate concentration. Therefore, some level of advanced oxidation occurs during natural ozonation.

A typical RCT value is 10-8 in conventional ozone application (without hydrogen peroxide). In AOP the RCT value is 10-6 where . Hydroxyl ion exposure is 100 times greater than during conventional ozonation. In many ozone applications, hydroxyl ion exposure is sufficient to oxidize background levels of organic micropollutants. Enhanced hydroxyl ion exposure is necessary to satisfactorily oxidize elevated concentration of these compounds. The degree of enhancement depends on pH. Several drinking WTP are designed with the flexibility to add peroxide to increase hydroxyl ion based reactions if needed.

AOP-Effectsof otherparameters

In the study conducted by Westerhoff et al. (2006) the effect of ozone oxidation by parameters such as pH, ozone and hydrogen peroxidedosage and water quality parameters such as temperature on the

FigureE1:Reactionpathwayof ozoneinwater

(Source: J Hoigne and H. Bader (1979), “Role of Hydroxyl Radical Reaction in Ozonation Process in Aqueous Solutions”)

TableE.5:Factors affectingGeosmin RemovalusingOzoneandHydrogen PeroxideAOP

removal of MIB/geosmin was investigated. Hydroxyl radical scavenger during the reaction significantly impacted the removal efficiency. The results showed that removal efficiencies of MIB/geosmin increased with increase in ozone dosage, temperature, pH and hydrogen peroxideconcentration. An empirical model was developed to predict bromate formation, CT requirement and odorant oxidation, which are all interconnected. The CT ratio of hydroxyl radical to ozone was found to be the most critical factor for oxidation of MIB/geosmin. Liang et al. (2007) also found that pH is a significant factor influencing oxidation as it is directly related to the hydroxyl radical concentrations.

Low pH conditions favor the slow direct oxidation reaction involving ozone and high pH condition or high organic matter favor auto decomposition route. However, high concentration of bicarbonate and carbonate buffer, especially carbonate buffer reduce the rate of decomposition by scavenging hydroxyl radicals. This means that ozone residuals last longer at low pH and in highly buffered water. Water temperature, the initial ozonedose, as well as ozone+hydrogen peroxide ratios are all affecting geosmin and MIB ozonation.

Process Unitsand Equipment

The Ozone+Hydrogen Peroxide AOP employs the following equipment as shown in Figure E.2, hydrogen peroxide storage and injection system,ozone generator and injection system, contactor and mixing tanks, ozone off gas destruct unit, supply and discharge pumps, and monitoring and control systems. Hydrogen

FigureE.2: Schematicof OzoneContactorinozone+hydrogenperoxideAOP (Source: Xylem (2019))

peroxide is fed from an aqueous solution, at peroxide to ozone ratios ranging from 0.3:1 to 3:1. The specific ratio will be a function of disinfection requirements, bromide concentration, contaminant concentration, and other water quality parameters.

OtherApplications/Benefits

Recent studies illustrate the effectiveness of ozone+hydrogen peroxide AOP in treating a wide range of constituents of emerging concern such as atrazine, caffeine, carbamazepine, primidone, and tris (2chloroethyl) phosphate (MWDSC, 2014). The ozone+hydrogen peroxide AOP can treat Benzene, Toluene, Ethylbenzene, and Xylene (BTEX), chlorinated solvents, methyl tertiary butyl ether, (MTBE), petroleum hydrocarbons, and volutile organic carbon in soil and groundwater. Additionally, the ozone +hydrogen peroxide AOP can be used in wastewater treatment. Ozone is dosed at a ratio of 1 to 2 mg/L ozone per mg/L DOC; however, higher dosages are recommended for source waters with high alkalinity (>100 mg/L as calcium carbonate) or NOM

The combined ozone/hydrogen peroxide AOP has been demonstrated to be more effective at removing natural and synthetic organics than ozone or hydrogen peroxide alone. In addition, using a combination of ozone and hydrogen peroxide to produce hydroxyl radicals, rather than just ozone, allows a lower dosage of ozone to be used. The theoretical yield of hydroxyl radicals via ozone+hydrogen peroxide technology is less than that of the hydrogen peroxide/UV technology; however, the yield is less affected by water quality (i.e., turbidity, iron, and nitrates lower the yield for UV processes but not ozone+hydrogen peroxide AOP ).

Both ozone oxidation and hydroxyl radical oxidation of cyanotoxins is generally quite fast, though the amount of oxidation depends on pH, temperature, and dose.

Another important aspect of the AOP is the influence on organic precursors and DBP formation, which is an advantage when compared to ozone. There is risk of formation of harmful disinfection byproducts through these processes such as as aldehydes, ketones and brominated DBPs in water containing bromide (White, 2010).

Section E: Additionalinformation on UV+Hydrogen Peroxide AOP

Effectsof other parameters

The efficiency of MIB and geosmin oxidation with AOP is negatively affected by background constituents such as NOM or carbonate alkalinity species. Because of the relatively poor UV absorbance of hydrogen peroxide, large doses of hydrogen peroxide(2–10 mg/L) must be added in order to generate effective AOP conditions. Little of this hydrogen peroxide is consumed across the UV reactor (e.g., 5–10%); therefore, a large hydrogen peroxide residual must be quenched. The effectiveness of UV+Hydrogen Peroxide-AOP is dependent on source water characteristics such as UV oxidation performance, UV transmittance, pH, nitrate ion concentration, radical scavenging and NOM concentrations.

The capital and energy costs associated with these technologies can be significantly high, especially for large scale applications. Figure E.3 illustrates the schematic of UV+Hydrogen Peroxide AOP

Mechanism

UV based oxidation requires two components: UV light and an oxidant such as hydrogen peroxide. When UV light is introduced into drinking water, the dissolved hydrogen peroxide molecules absorb UV light. Highly energetic and reactive hydroxyl radicals are then formed. Contaminants are destroyed by UV light or broken down and oxidized by hydroxyl radicals. The hydroxyl radical reacts rapidly with organic constituents in the water, including T&O compounds, breaking them down into their elemental, nonodorous components.

H2O2 + υ→. 2 •OH

AOP

The highly reactive hydroxyl radical species can quickly react with organic species in the water. The observed improvement in destruction with the addition of hydrogen peroxide is due to the fact that the dominant mechanism of treatment when hydrogen peroxide is present under UV irradiation is hydroxyl radical based advanced oxidation.

Figure E.3: Schematicof UV+hydrogenperoxide-AOP

Figure E.4: Schematicof UV+Hydrogen Peroxide

(Source: Xylem (2019))

(Source: Pantin, (2009)

TableE.6:Factors affectingGeosmin RemovalusingUV+Hydrogen PeroxideAOP

Increase in Hydrogen Peroxide Dosage

High concentration of Bicarbonate and Carbonate buffer

Presence of Nitrate and Bromide ion

Presence of Organic Matter

Because of the relatively poor UV absorbance of hydrogen peroxide, large doses of hydrogen peroxide (2–10 mg/L) must be added in order to generate effective AOP conditions

To generate advanced oxidation conditions with UV light, UV reactors need to be designed to deliver approximately 10 times more energy than those used in UV disinfection systems (i.e., UV AOP requires around 400 mJ/cm2 versus 40 mJ/cm2 for disinfection). While UV energy alone at 400 mJ/cm2 is not sufficient to photolyze cyanotoxins, by adding hydrogen peroxide to the water passing through the UV reactor(s), hydroxyl radicals are formed that can oxidize cyanotoxins in addition to T&O compounds. Several utilities have installed such systems specifically, for seasonal T&O control with a co-benefit of providing excellent cyanotoxin control. Figure E.3 illustrates the schematic of UV+Hydrogen Peroxide AOP The factors affecting geosmin/MIB removal efficiency using UV+Hydrogen Peroxide AOP is illustrated in Table E.6. The capital and energy costs associated with these technologies can be significantly high, especially for large scale applications.

Section F:Additional information on UV+ozoneAOP

In UV ozone process, photons in the UV convert ozone in the presence of water into oxygen and peroxide. Peroxide reacts with the ozone to form the hydroxyl radical. Oxidation of organic matter occurs due to the reaction with hydroxyl radicals, ozone and direct photolysis. The major components of an UV+ozone system include: UV lamps, lamp sleeves, and lamp cleaning system, ozone generator and diffusers, ozone contactor, ozone off-gas decomposer, oxygen or air feed systems, supply and discharge pumps and piping, monitoring and control systems. Since ozone absorbs UV light at 254 nm, low pressure UV (LPUV) lamps are used. The two primary design variables that must be optimized in sizing a UV AOP system are the UV power radiation per unit volume of water treated more commonly referred to as UV dose and the concentration of ozone. The dose of UV light and ozone required per unit volume of water treated may vary depending on the water to be treated.

UV light penetration into the source water can be adversely affected by turbidity. There are also many interference compounds that absorb UV light (e.g., nitrate and iron) and, thus, reduce process efficiency. This technique is ideal for NDMA, excellent for low concentrations of contaminants in very clean groundwater and RO effluent

Section G:Additional information on UV+ozone+HydrogenPeroxide AOP

In UV+ozone+hydrogen peroxide AOP, oxidants are added in different combinations to increasing the hydroxyl radical production thereby improving the efficiency of the overall oxidation process by. The selection of appropriate treatment technology depends on the source water quality, the expected treatment outcome and overall cost.

A comparison between the MIB/geosmin removal efficiency between various treatment techniques is shown in Table E.7.

TableE.7: Treatment Techniquesand MIB/Geosmin Removal Efficiency

Table E.8 lists the advantages and limitations of each treatment technique.

TableE.8: Advantagesand Limitation of Various Treatment Techniques

Treatment Technique Advantage Limitation

> Black water caused by inadequate coagulation

> Dust -major problem in dry feed system

> Increase in solid production and increased frequency of backwashing filters or removing sludge from sedimentation basins

PAC > Can be dosed on an as-needed basis

Biological Treatment

>Suitable for treating moderate concentration of MIB/Geosmin (<50ng/L)

>Can be used to provide additional disinfection

UV

Ozone

>No formation of by-products such as THMs or bromate

> Provide additional benefits such as: improved particulate removal, reduced coagulant dose, iron and manganeese removal etc

>Lower chlorine levels if sufficient residual exisits to provide disinfection credit

>Smaller footprint compared to ozone

>Nearly instantaneous treatment

>Potential to reduce toxicity of organic compounds

>No increase in solids production, improved filtration runs due to improved coagulation & flocculation (less chemicals used) (pre-ozonation)

>Superior Geosmin and MIB removal compared to PAC

>Can be used to provide additional disinfection

>Cost advantages for T&O at extreme concentrations.

AOP

>Lower carbon footprint

>Does not concentrate waste for further treatment, such as membranes. Does not create sludge as with physical chemical process or biological processes (wasted biological sludge)

>Does not produce “spent carbon” such activated carbon absorption

> Easily automated and controlled

> Reduced labor input

>Remove color associated with naturally occurring iron and manganese, and establish resilience against algae-linked compounds and other contaminants of emerging concern (CECs).

> High operational cost

> High carbon footprint compared to alternative techniques

> During intense T&O events may not remove sufficient T&O to avoid consumer complaints

> Presence of NOM reduces its capacity

> Highly dependent on biodegradable organic matter (BOM) characteristics, concentrations in the influent of biofilters, the transient nature of odor events, seasonal water temperature variations, filter media, empty bed contact time, and hydraulic loading rate

> Increase in solid production and increased frequency of backwashing filters

>Effectiveness of this process is largely dependent on the organic content of the water.

>Not cost-effective for geosmin removal since higher doses are required

> Formation of bromate as a DBP when used in water containing bromide.

>Production of additional sludge

> Presence of radical scavengers such as natural organic matter and alkalinity reduces process efficiency

> Byproduct formation must be fully characterized to avoid adding toxicity.

>Capital intensive

>For some applications quenching of excess peroxide is required

Item

PumpingStation

APPENDIXE Part 6.4

HorsePowerbasedonpeak flow

Includecostforpumps,housing,motors,sitework, andallmaterialsneeded.Electricalconnectioncosts arebasedon$150/HP

Pipeline

Diameter,soil/urbanization condition,length,pressure class

Includeinstallationcostofthepipelineand appurtenances,suchasmarkers,valves,thrust restraintsystems,corrosionmonitoringandcontrol equipment,airandvacuumvalves,blow-offvalves, erosioncontrol,revegetationofrights-of-way,fencing andgates.

Pipelinecrossings

Typeofcrossing-2lane roads,highways,railways, creeks,HDD,Utiltiy

WaterTreatmentPlant Ratedcapacity

Includecostsforallprocessesrequired,sitework, buildings,storagetanks,sludgehandlinganddisposal, clearwell,pumpsandequipment.Thecostsassume pumpingthroughandoutoftheplantincluderaw waterpumpingintotheplantforatotalpumpinghead of100feet,andfinishedwaterpumpingfor300feetof totalhead.AnnualO&Mcostsarebasedontheplant size

Thecostforthetreatmentprocessincludescoagulant andpolymeraddition,rapidmix,flocculation,settling, filtration,anddisinfectionwithchlorine.

Note: includethecostsofaHSPSifthe WTPisnotdeliveringdirectlytoadistributionsystem.

Other Project Costs

Engineering,Legal, Financingand Contingencies

LandAcquisition-Land Purchase, Permanent& TemporaryEasement

Percentagetothetotalcapital cost

LandAreaforFacility: PumpingStation:5acres WTP:0.5/MGD EasementWidth

Pipeline:30%

OtherFacility:35%otherfacilities.

Percentageoflandcost 10% Environmentaland ArchaeologyStudies, Permitting,and Mitigation

Surveying

InterestDuring Construction

Annual Costs

Debtservice (repaymentofborrowed funds)

Operationand Maintenance

PumpingEnergyCost

ConstructionPeriod

Pipeline:1year

OtherFacility:Xyear

Pipeline:$25,000/mile

OtherFacility:100percentoflandcosts

InterestduringConstruction:3%

RateofReturnonInvestment:0.5%

Totalprojectcost(present worth),theprojectfinance rate,andthefinanceperiodin years 3.5%for20years

Pipeline:1%ofConstructionCost

IntakeandPumpStation:2.5%ofConstructionCost WTP:Basedonplantsize

Basedonpowerrateand powerload $0.08/kilowatt-hour

APPENDIXE Part 6.5

CostEstimating Worksheet

TYLER-NEW RAWWATERLINEFROMLAKETYLERTO LAKEPALESTINE WTP

CyanotoxinTesting

The EXO3 Multiparameter Sonde from YSI includes five total sensor ports available for use. The central port should be reserved for a wiper due to the installation of this instrument long term as opposed to a lab application. A conductivity-temperature sensor is required to operate the sonde and a Total Algae sensor will comprise the other two sensors designated for qualitative cyanotoxin monitoring. Two sensors will remain vacant should the City decide to measure other parameter. This model can be made compatible with Modbus protocols for integration into the City’s SCADA system. The maintenance on the EXO3 consists generally of service every 2-3 months with calibration more often as the City’s staff sees fit. The depth of the sonde can be adjusted to match the active intake pumps, or multiple sondes can be placed at different depths for the same purpose. Installation should include a piece of PVC pipe punctuated with holes to protect the sensor from being knocked against hard surfaces underwater while allowing flow into the sensor. All EXO sensors are user-replaceable, allowing staff to simply plug in additional sensors into the instrument. The only configuration required is selection of the units in which the parameter is reported.

The cost of a single EXO3 sonde with a 100-meter depth, conductivity-temperature sensor, central wiper, and Total Algae sensor is $11,060. A 33-meter able and Modbus converter is $1,990 bringing the total for relevant materials up to $13,050 Conservatively accounting for the cost of labor and shipping to complete the installation and network connection in place, this cost becomes $19,575 If the City begins using multiple sondes it should consider the potential benefit of instead modifying one sonde with a fixed profiler instead for an additional cost of approximately $70,000.

TOCTesting

The Hach BioTector 3500dw is an instrument compatible with drinking water systems and long-term application. The analyzer itself typically requires maintenance twice a year A single-stream model is estimated to cost approximately $30,000 without the cost of shipping and installation.

APPENDIX F

Budget Proposal

Tyler, TX-Lake Palestine WTP

Prepared for:

Halff Associates

Preston Dillard PE

October 18, 2022

Xylem Water Solutions USA, Inc.

4828 Parkway Plaza Blvd., Suite 200

Charlotte, NC 28217

Halff Associates

Preston Dillard PE

Project Name: Tyler, TX-Lake Palestine WTP

Project Number: J22031042635

Revision Number: 1

Dear Preston Dillard PE,

October 18, 2022

We are pleased to submit the following proposal for the Tyler, TX-Lake Palestine WTP ozone opportunity based on the information provided within your inquiry.

This proposal includes the replacement of the two (2) existing WEDECO PDO 4000 generators & PSUs. The proposal also includes the equipment required for the expansion of 15 MGD.

Please refer to our local representative Eric Fields of EI2, 214-783-7312 or us if you have any questions. We look forward to working with you on this exciting project.

Sincerely,

Lucinda Jooste - Central US

Josiah Wallace Territory Manager Lead Application Engineer 980-216-9473

Project number: J22031042635

Date: October 20, 2022

1 Xylem Overview

Xylem is a leading global water technology provider, enabling customers to transport, treat, test and efficiently use water in public utility, residential and commercial building services, industrial and agricultural settings. The company does business in more than 150 countries through a number of market-leading product brands, and its people bring broad applications expertise with a strong focus on finding local solutions to the world’s most challenging water and wastewater problems.

Xylem’s treatment business offers a portfolio of products and systems designed to effectively meet the demands and challenges of treating water and wastewater. From smarter aeration to advanced filtration to chemical-free disinfection, Xylem leverages its well-known Treatment brands, Flygt, Leopold, Sanitaire, and Wedeco, to offer hundreds of solutions backed by a comprehensive, integrated portfolio of services designed to ensure we can meet our customers’ needs in a number of different industries including municipal water and wastewater, aquaculture, biogas and agriculture, food and beverages, pharmaceuticals, and mining.

Our scientists and engineers utilize their deep applications expertise and continually listen and learn from our customers’ situations to create solutions that not only use less energy and reduce life-cycle costs, but also promote the smarter use of water.

Wedeco has accepted the challenge of the 21st century. With the Wedeco brand for UV Disinfection, ozone oxidation & AOP solutions, we own the advanced technologies for chemical-free and environmentally friendly treatment of drinking water, wastewater and process water as well as further industrial treatment processes. We constantly invest a large portion of our energy in the development of high-tech components, systems and equipment, as well as in the study of new areas of application for UV, ozone & AOP. In doing so, we have always given special attention to the increase in energy efficiency of our Products equipped with our unique UV lamps and ozone electrodes.

The special characteristics of the Wedeco Ecoray UV lamp are its special doping and the unique long-life coating. Because of these futures, a constantly high UV light yield is achieved with a substantially extended lamp service life at the same time. In addition, by using this technology it is not necessary to apply liquid mercury inside the lamp. Wedeco UV lamps cannot be surpassed in economic efficiency.

In relation to expenditure of energy, the High-Intensity/LowPressure Technology provides a light yield three times higher than comparable UV lamps of widely used Medium Pressure Technology. A higher light yield also means a lower heat generation at the same time.

Thanks to this, Wedeco UV lamps become less susceptible to varying water temperatures. Even the formation of deposits on the quartz sleeves as well as lamp aging is considerably lower than with alternative UV lamp technologies in Herford and Essen.

Xylem's Wedeco ozone systems combine maximum flexibility and reliable operating characteristics for small to large ozone capacities. The ozone generator system and control unit can be combined and supplemented with option sets that allow for various application requirements.

Effizon evo 2G ozone electrodes are the core of our technology and achieve an unmatched level of reliability and energy efficiency. The electrodes are manufactured completely from inert materials, without the need for fuses or coatings, making them highly resistant to corrosion. This means that the Wedeco ozone generators are practically maintenance free with no need for regular cleaning or replacement of the electrodes.

We rely on consistently high-quality standards in all divisions of the company. Moreover, product quality and manufacturing operations are constantly monitored and optimized in continuous improvement processes. Established quality controls give Xylem and you the security of knowing that Wedeco UV, Ozone & AOP systems will always operate reliably.

For more information please visit us at http://www.xylem.com/treatment/

WEDECO Effizon® evo 2G Ozone electrode

WEDECO Ecoray UV lamp

2 General Process Description

2.1 Design

o Ratio

PSU has a turndown ratio of 100:1 (1000 Hz to 10 Hz); however this number is limited by the turndown capabilities of the instrumentation within the equipment which is 10:1

2.2 Process Description

The proposed ozone generation system is based on a maximum ozone production 650 ppd per ozone generator @ 10%wt with an open loop water temp of 70°F. The system will have the ability to dose hydrogen peroxide at a 2:1 ratio O3/H2O2 for additional MIB/Geosmin reduction when the raw water experiences spikes.

3 Technical Description

3.1 Physical Information

 PSU

o Weight: ~ 7,000 lbs

 Generator

o Weight: ~5,750 lbs

 CLCW Skid

o Weight: ~ 1,880 lbs

 Destruct Skid

o Weight: ~ 2,950 lbs

 Nitrogen Generation System

o Weight: ~ 500 lbs

3.2 General plant requirements

3.2.1 Ambient air requirements

 Ambient air temperature  95 °F

 Humidity (non-condensing)  90 %

 Altitude above sea level <1,600 ft

3.2.2 Electrical power supply

3.2.3 Others

 Feed Gas Quality Refer to WEDECO Feed Gas Specification



Project number: J22031042635

Water Quality Refer to WEDECO Cooling Water Specification

4 Price & Scope of Supply

4.1

Scope of Supply-Replacement

4.2

Scope of Supply-Expansion

4.3 Budget Price

4.4 Notes

 The extended lead times for PLC components, actuators, valves and instruments has impacted our overall equipment lead times. We are continually monitorng market conditions thus our lead times are subject to change.

5 Commercial Terms & Conditions

 All prices stated in USD

 Price quoted is budgetary and is not a binding offer. Pricing is based on preliminary information and should not be used for design purposes.

 The proposed budgetary price within this document is valid for Forty-Five (45) days from date of submission.

 All process requirements, including electrical power, cooling water fill, and oxygen (if applicable) are provided by others.

 Freight, Incoterms 2020 DAP destination. Title and risk of loss will transfer to buyer upon delivery. Offloading and arrangement of the equipment is not included.

 Typical lead times are noted below.

 Unless otherwise noted, the system design and pricing is based upon WEDECO Standard PIDs.

APPENDIX G

APPENDIX H

NOTE:

DRAWING IS NOT TO SCALE.

SITE PLAN IS APPROXIMATE

BASED ON AVAILABLE RECORD

DRAWINGS AND AERIAL IMAGES.

Categories:

Appendix I

Facilities Master Plan CIP

Category 1: Golden Road WTP Rehabilitation

Category 2: Lake Palestine WTP Rehabilitation and Expansion

Category 3: Lake Tyler Raw Water Facilities Rehabilitation

Category 4: Lake Palestine Raw Water Facilities Rehabilitation

Category 5: Southeast WTP (if needed)

Category Order:

Category 1 should be completed alongside to Category 2 to ensure Golden Road’s rehabilitation is on track for full function by 2032 while maintaining a Lake Palestine expansion schedule to accommodate function by 2037. Upon completion of the evaluations at Golden Road the City can confirm the selection of the Golden Road WTP rehabilitation option and revise the sequence of projects that prioritizes rehabilitation and expansion appropriately Category 3 is the most critical due to highest risk. Category 5 is included for informational purposes only and are not to be executed unless the Golden Road WTP assessments uncover unforeseen issues.

Outcome:

• Rehabilitation of elements reaching their end of service life that are crucial components of Golden Road WTP functionality long term

• Implementation of improved geosmin treatment with hydrogen peroxide injection at Lake Palestine WTP

• Maintenance of existing treatment train at Lake Palestine WTP

• Expansion of Lake Palestine WTP to a fully operable 60 MGD by 2057 according to this schedule. Current demand projections show Lake Palestine outgrowing its first 15 MGD expansion by 2057, but not requiring production of the full 60 MGD should not be needed until after 2072.

Assumptions:

The costs herein do not account for land cost at either treatment plant. Lake Palestine is assumed to expand onto City-owned property directly north of the existing treatment train. This CIP also assumes the City is acting on recommended implementations from the Initial Operational Evaluation report by eHT in 2015 for Lake Palestine and Golden Road WTP. Those recommendations are listed in Table 4.3 in chapter 4 of the Water Facilities Master Plan.

1The need, cost, and schedule of these projects are subject to change based upon the results of the PlantWide Assessments. The CIP should be updated once the assessments are complete and the results analyzed.

WTP and pipeline costs were determined using the TWDB spreadsheet, which uses 2019 dollar estimates, and then scaled according to inflation rates in 2022. All other costs were already estimated in 2022 dollars. Operational and maintenance costs are not included. Annual costs are also omitted, keeping this CIP focused on overall capital costs projected onto future dates. The costs are reflective of present value estimations. Equipment called for replacement in this document were determined using the end of service life information from the asset inventory located in Appendix A.

CATEGORY 1

Golden Road WTP Rehabilitation

Group 1: Group 1 consists of the Plant-wide Assessments. The assessments will be used to confirm the decision made to rehabilitate the GR WTP instead of building a new SE WTP. Upon completion of the assessments, the subsequent Groups within Category 1 will be reviewed, project costs revised, and schedules updated. The electrical assessment that is currently in progress should be reviewed alongside a thorough mechanical evaluation to develop a rehabilitation plan.

Group Summary

1. Electrical assessment (in progress)

2. Plant-wide assessment – mechanical evaluation

Cost Estimate & Funding/Grant Information

Group 2: Group 2 consists of all Golden Road replacements associated with equipment reaching their end of service life by 2025. Based on the results of the Plant-wide Assessment, certain components may be replaced sooner or later than the fiscal year identified in Table 8.1 of the Water Facilities Master Plan.

Group Summary

1. 48-inch clarified water pipe

2. Four rapid mixers

3. 24-inch coagulated water pipe

4. 33-inch drain pipe

Cost Estimate & Funding/Grant Information

Group 3: Group 3 consists of all Golden Road replacements associated with equipment reaching their end of service life by 2028. Based on the results of the Plant-wide Assessment, certain components may be replaced sooner or later than the fiscal year identified in Table 8.1 of the Water Facilities Master Plan.

Group Summary

1. Electrical rehab projects from the Plant-Wide Assessments

2. Additional rehab projects from the Plant-Wide Assessments

3. Clariflocculator Basin #2

4. Clear Well #1

5. 36-inch Concrete Coagulated Water Pipe

Cost Estimate & Funding/Grant Information

Group 4: Group 4 consists of all Golden Road replacements associated with equipment reaching their end of service life by 2031. Based on the results of the Plant-wide Assessment, certain components may be replaced sooner or later than the fiscal year identified in Table 8.1 of the Water Facilities Master Plan.

Group Summary

1. Additional electrical rehab from the Plant-Wide Assessments

2. Additional rehab projects from the Plant-Wide Assessments

Cost Estimate & Funding/Grant Information

Group 5: Group 5 consists of the high-service pump station. The asset inventory identifies all four high-service pumps reached their end of service life in 2022, but a full restoration of Golden Road WTP involves replacing this pump station in its entirety. Timing of this project is triggered by the City’s decision to start up the proposed Lower Pressure Plane (LPP), described further in the Water Distribution Master Plan. To serve the new LPP most efficiently, some of the pumps in the new HSPS would need to be at a lower head capacity. And a new HSPS will decrease O&M requirements that are necessary for the existing HSPS, provide for easier and more reliable operation, and could eliminate flooding concerns.

Group Summary

1. New high-service pump station

2. 30-inch and 36-inch high pressure lines at pump station

Subtotal: $8,408,500

30% Contingency: $2,522,550

Land Costs: $0

Total Construction: $10,931,050

Engineering + Surveying: $1,307,989

Total Group Cost: $12,239,039

Group 6: Group 6 consists of Clear Well Number 2, the final component set to expire in 2039. The projects outlined in Category 1 extend to the year 2043, omitting those components in the asset inventory that reach their end of service life beyond this point.

Group Summary

1. Clear Well #2

Cost Estimate & Funding/Grant Information

Subtotal: $3,000,000

30% Contingency: $900,000

Land Costs: $0

Total Construction: $3,900,000

Engineering + Surveying: $466,667

Total Group Cost: $4,366,667

Group 7: Group 7 consists of butterfly valves set to expire in 2046. The projects outlined in Category 1 extend to the year 2047, omitting those components in the asset inventory that reach their end of service life beyond this point.

Group Summary

1. One 20-inch butterfly valve, four 24-inch butterfly valves, and two 48-inch butterfly valves

Cost Estimate & Funding/Grant Information

One 20-inch, Four 24-inch, and Two 48-inch Butterfly Valves

Subtotal: $615,775

30% Contingency: $184,733

Land Costs: $0

Total Construction: $800,508

Engineering + Surveying: $95,787

Total Group Cost: $896,295

CATEGORY 2

Lake Palestine WTP Rehabilitation and Expansion

Group 1: Group 1 consists of replacing ozone generators and pilot testing for the new ozone/AOP treatment system for treating geosmin in water. The AOP pilot testing assumes use of a MiPRO Container for six months of pilot testing covering the City’s typical high-geosmin periods. On top of the monthly rental fee there are shipping and setup fees, training and startup costs, and a decommissioning cost at the end of the rental period. The City will be responsible for offloading at the Lake Palestine WTP with a crane or large fork truck with a ten-ton lift capability. If the original piloting is executed properly and produces usable data, a second or third pilot testing should not be necessary for the two 15 MGD expansion phases at the plant. The six month testing period would provide adequate information for the design of the AOP system. These projects are likely eligible for the TWDB Emerging Contaminants loan forgiveness program.

Group Summary

1. Geosmin treatment pilot testing

2. Replace two ozone generators

Cost Estimate & Funding/Grant Information

Group 2: Group 2 consists of upgrades to the geosmin testing and treatment systems. The enhanced operation replaces existing monitors and adds a hydrogen peroxide dosing system that will assist in periods with higher geosmin concentrations. The hydrogen peroxide dosing setup will inject directly into the raw water line ahead of the split between the current treatment train and the anticipated expansion at Lake Palestine WTP. Group 2 is contingent upon completion of the pilot testing in Group 1. These projects are likely eligible for the TWDB Emerging Contaminants loan forgiveness program.

Group Summary

1. Updated geosmin treatment (ambient monitors, H2O2 dosing system, freight and field service)

2. Geosmin-related testing instrumentation (TOC and cyanobacteria monitors)

Cost Estimate & Funding/Grant Information

$241,638

$0

Group 3: Group 3 consists of improvements to the ozone injection system and replacing butterfly valves that reach their end of service life by 2033 The current ozone mixing system expiring in 2032 is less efficient than the side-stream injector proposed, though the new equipment does require the contactor basin be compatible with it. Due to the current basin’s age the cost estimated accounts for construction of a new basin with approximately the same volume. In advance of these upgrades the City can engage the manufacturer and a structural engineer to determine if the current basin has the structural integrity to be effectively modified for the new equipment. Projects 1 and 2 are likely eligible for the TWDB Emerging Contaminants loan forgiveness program.

Group Summary

1. Side-stream injector to replace existing contactor diffuser

2. New ozone contactor basin

3. Eight 48-inch butterfly valves and two 36-inch butterfly valves

Cost Estimate & Funding/Grant Information

Group 4: Group 4 consists of the design and construction of the first 15 MGD expansion at Lake Palestine WTP This includes a 48-inch pipeline extension from the existing stub-out to the southwest and integration of advanced geosmin treatment technology. The hydrogen peroxide dosing system applied in Group 2 serves both the existing treatment train and this new extension so there is no further cost required to establish its use on the new train.

Group Summary

1. Design and construction of 15 MGD expansion, including 48-inch pipeline extension from existing stub-out and advanced geosmin treatment facilities

Cost Estimate & Funding/Grant Information

The design and construction of a the 15 MGD treatment train expansion at the Lake Palestine WTP would potentially be eligible for funding from the following programs:

• DWSRF: Drinking Water State Revolving Fund

• SWIFT: State Water Implementation Fund for Texas

• Water Infrastructure Finance and Innovation Act

Group 5: Group 5 consists of replacing equipment that reaches its end of service life in 2038 at Lake Palestine WTP. Based on updated condition assessments, the City may choose to pursue these updates sooner or later than the fiscal year identified in Table 8.1 of the Water Facilities Master Plan.

Group Summary

1. Six rapid mixers, two blowers with motors, two ozone destruct units, and one nitrogen generator

Cost Estimate & Funding/Grant Information

Subtotal: $1,659,000

30% Contingency: $497,700

Land Costs: $0

Total Construction: $2,156,700

Engineering + Surveying: $258,067

Total Group Cost: $1,917,067

Group 6: Group 6 consists of the remaining replacements at Lake Palestine WTP based on end of service life through 2047 The components in this group include high-service pumps, backwash pumps, and circulation pumps.

Group Summary

1. Four high-service pumps, two backwash pumps, and two circulation pumps

Cost Estimate & Funding/Grant Information

Subtotal:

30% Contingency: $1,563,240

Land Costs: $0

Total Construction: $6,774,040

Engineering + Surveying: $810,569

Total Group Cost: $7,584,609

CATEGORY 3

Lake Tyler Raw Water Facilities Rehabilitation

Group 1: Group 1 consists of the raw water facilities at Lake Tyler supplying Golden Road WTP that are reaching or have reached their end of service life. After the Plant-wide assessment, the City should have up-to-date about the conditions of current raw water components with which to develop a schedule for the rehabilitation. These components may be replaced sooner or later than the fiscal year included in Table 8.1 of the Water Facilities Master Plan Report.

Group Summary

1. Assessment of raw water infrastructure

Coordination with Asset Management Plan

Cost Estimate & Funding/Grant Information

1Cost has been accounted for in the TWU Budget provided. See Table 8.2 in the Water Facilities Master Plan.

Group 2: Group 2 consists of replacement raw water facilities at Lake Tyler supplying Golden Road WTP that are reaching or have reached their end of service life. After the Plant-wide assessment, the City should have up to date about the conditions of current raw water components with which to develop a schedule for the rehabilitation. The raw water piping assessed as part of Group 1 is a highly critical component of the City’s production and any should be prioritized as soon as replacements are needed. The concrete standpipes are a part of the raw water supply system that should be assessed for overall condition so the City can determine an appropriate replacement schedule.

Group Summary

1. Replace raw water piping of the following sizes and linear footage: 32,000 feet of 27-inch pipe, 11,164 feet of 30-inch pipe, 31,750 feet of 36-inch pipe, and 11,887 feet of 42-inch pipe

2. Two 72-inch concrete standpipes

Cost Estimate & Funding/Grant Information

$40,120,980 30% Contingency: $12,036,294 Land Costs: $0 Total Construction: $52,157,274 Engineering + Surveying: $6,241,041

Total Group Cost: $58,398,315

Group 3: Group 3 consists of two valves and a water meter located near the intake at Lake Tyler. These components reach their end of service life by 2029 and should be assessed for flaws and a replacement schedule established.

Group Summary

1. 12-inch Surge anticipator valve and surge protector valve at intake

2. Raw water meter

Cost Estimate & Funding/Grant Information

Subtotal: $94,000

30% Contingency: $28,200

Land Costs: $0

Total Construction: $122,200

Engineering + Surveying: $14,622

Total Group Cost: $136,822

Group 4: Group 4 consists of one raw water intake pump at Lake Tyler serving Golden Road WTP. It is set to reach its end of service life in 2043 and should be observed to prevent failure and interruption to Golden Road’s raw water supply.

Group Summary

1. Raw water pump #2 (1250 HP) at intake

Cost Estimate & Funding/Grant Information

30% Contingency: $434,250

Land Costs: $0

Total Construction: $1,881,750

Engineering + Surveying: $225,167

Total Group Cost: $2,106,917

CATEGORY 4

Lake Palestine Raw Water Facilities Rehabilitation

Group 1: Group 1 consists of evaluating the raw water facilities at Lake Palestine supplying Lake Palestine WTP. Whether or not they are reaching or have reached their end of service life, the City should evaluate existing conditions and develop a schedule for the rehabilitation that is consistent with the expected schedule for the LP WTP expansion projects.

Group Summary

1. Evaluate condition of raw water lines and establish rehabilitation schedule (subject to change)

Cost Estimate & Funding/Grant Information

Subtotal: $1,000,000

30% Contingency: $300,000

Land Costs: $0

Total Construction: $1,300,000

Engineering + Surveying: $155,556

Total Group Cost: $1,455,556

Group 2: Group 2 consists of the raw water lines from Lake Palestine supplying Lake Palestine WTP that are reaching or have reached their end of service life. The City should have evaluated existing conditions in the Group 1 project and developed a schedule for the rehabilitation that is consistent with the expected schedule for the LP WTP expansion projects.

Group Summary

1. Raw water line rehabilitations

Cost Estimate & Funding/Grant Information

Group 3: Group 3 consists of the raw water facilities at Lake Palestine supplying Lake Palestine WTP that are reaching or have reached their end of service life. The City should evaluate existing conditions and develop a schedule for the rehabilitation that is consistent with the expected schedule for the LP WTP expansion projects.

Group Summary

1. 16-inch Surge anticipator valve, 16-inch surge relief valve, raw water meter

Cost Estimate & Funding/Grant Information

Subtotal: $98,000

30% Contingency: $29,400

Land Costs: $0

Total Construction: $127,400

Engineering + Surveying: $15,244

Total Group Cost: $142,644

Group 4: Group 4 consists of the raw water facilities at Lake Palestine supplying Lake Palestine WTP that are needed to support the expansion to a full 60 MGD

Group Summary

1. Two raw water intake pumps (new)

Cost Estimate & Funding/Grant Information

Group 5: Group 5 consists of the raw water facilities at Lake Palestine supplying Lake Palestine WTP that are reaching or have reached their end of service life. The City should evaluate existing conditions and develop a schedule for the rehabilitation that is consistent with the expected schedule for the LP WTP expansion projects.

Group Summary

1. Three raw water intake pumps (replacements)

Cost Estimate & Funding/Grant Information

Subtotal: $3,759,000

30% Contingency: $1,127,700

Land Costs: $0

Total Construction: $4,886,700

Engineering + Surveying: $584,733

Total Group Cost: $5,471,433

CATEGORY 5

Southeast WTP (if needed)

This category has been included in case the results of the Golden Road WTP Plant-Wide Assessments (Category 1, Group 1) show that the cost of rehabilitating the plant are too great.

Group 1: Group 1 consists of all major costs associated with the first phase of constructing a new water treatment plant designed to replace Golden Road in its service of the southeast portion of the City. These costs are presented in future value based on the fiscal years described in Alternate 1 of the Water Facilities Master Plan. The costs shown here are also displayed in Table 8.3 of the plan, compared to the differing schedules offered by Alternates 2 and 3. The unknown land costs below are expected to encompass all land necessary for the future expansion of the Southeast WTP as well.

Group Summary

1. Design and construction of raw water pipelines extending from Golden Road WTP to the new Southeast WTP site

2. Design and construction of first 15 MGD treatment train

Cost Estimate & Funding/Grant Information

The design and construction of a first 15 MGD treatment train at the Southwest WTP would potentially be eligible for funding from the following programs:

• DWSRF: Drinking Water State Revolving Fund

• SWIFT: State Water Implementation Fund for Texas

• Water Infrastructure Finance and Innovation Act

30% Contingency: $37,492,583

Land Costs: TBD

Total Construction: $162,467,858

Engineering + Surveying: Includedin Subtotal

Total Group Cost: $162,467,858

Group 2: Group 2 consists of all major costs associated with the second phase of constructing a new water treatment plant designed to replace Golden Road in its service of the southeast portion of the City. These costs are presented in future value based on the fiscal years described in Alternate 1 of the Water Facilities Master Plan. The costs shown here are also displayed in Table 8.3 of the plan, compared to the differing schedules offered by Alternates 2 and 3. The costs below assume that all land required for the Southeast WTP in its full form would be purchased as part of the projects in Group 1.

Group Summary

1. Design and construction of second 15 MGD treatment train

Cost Estimate & Funding/Grant Information

The design and construction of a second 15 MGD treatment train at the Southwest WTP would potentially be eligible for funding from the following programs:

• DWSRF: Drinking Water State Revolving Fund

• SWIFT: State Water Implementation Fund for Texas

• Water Infrastructure Finance and Innovation Act

30% Contingency: $24,060,381

Land Costs: $0

Total Construction: $104,261,651

Engineering + Surveying: Includedin Subtotal

Total Group Cost: $104,261,651