KUB Second Creek Wastewater Storage Facility

Second Creek Wastewater Storage Facility

Brownfield site is transformed into a beneficial, aesthetically pleasing wastewater facility Second Creek Wastewater Storage Facility

Like most of the country’s sanitary sewer collection systems, the Knoxville Utilities Board’s (KUB) system was old and deteriorated, a state that prompted the PACE 10 improvement program in 2004. As part of the program, KUB determined there was a need for a new storage facility to reduce peak flows to the Kuwahee Wastewater Treatment Plant. The new tank and pumping station, The Second Creek Storage Facility, was planned for a brownfield site formerly used as a manufactured gas plant. Despite unforeseen issues to an already challenging project, the completed facility not only addressed issues with the treatment plant and sewer system, it transformed the brownfield into a functional, neighborhood-friendly asset.

Client

Knoxville Utilities Board (KUB) Location

Knoxville, Tennessee Market

Water Services Services

Engineering Construction Administration

PRINCIPAL-IN-CHARGE

William J. Whitson, P.E. PROJECT MANAGERs

J. Dale Mosley Craig S. Parker, P.E. Project professional

Anthony Crist, P.E. Project ENGINEER

Michael L. Orr, P.E. ADDITIONAL

Marion J. Adamson, AIA Andrew Bratcher Chris Childress, LEED AP Kenneth Church, RLS Jason E. English, P.E. Eric Gamble Max Kenneth Koffman Christopher B. Lehman, P.E., LEED AP Jason Moseley, RLS Terence S. Mulvaney, RLA, CLARB Robert E. Oswalt, P.E. Kenneth A. Richards, P.E. Wayne Smithson Steven J. Snoddy, ASLA, LEED AP Liz Southard Ken Stewart, P.E. James R. Wilson, P.E., LEED AP

Awards

Tennessee Engineering Excellence Awards - Grand Award in the Water Category, ACEC of Tennessee

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his isn’t the first project GS&P has done for KUB. What is the scope of this and related projects?

Describe the condition of the collection system when GS&P became involved.

Craig Parker: The Second Creek tank is actually the fifth storage and pumping facility project we’ve been involved with for KUB. The primary function of the first four, which were done as a group, was to provide overflow abatement in the sewer collection system. The Second Creek tank and the Lower Third Creek tank are being constructed simultaneously to provide peak flow equalization for the Kuwahee Wastewater Treatment Plant. All six tanks are part of the KUB PACE 10 program.

Craig: Like most of the country’s sewer systems, the sanitary sewer collection system had deteriorated over time. Because of its age and condition, inflow and infiltration occurred during heavy rains, causing the flow in the system to exceed its capacity. Additionally, the Kuwahee Treatment plant would experience peak wastewater flows above the plant’s treatment capacity.

What is the Pace 10 Program?

Craig: PACE 10 stands for Partners Acting for a Cleaner Environment: A 10-Year Program to Improve Our Waterways. The PACE 10 program was formed to aggressively address Sanitary sewer overflows (SSOs) and treatment plant capacity issues.

SSOs and aging treatment plants are growing concerns across the entire nation. KUB, like many other utilities, is under a federal Consent Decree to make system improvements. Whereas the first four storage and pump station facilities were focused more on reducing the SSOs, these last two tanks are focused on treatment plant improvements.

The purpose of the Second Creek facility is to allow the operators at the treatment plant to divert flow from the sewer into the storage tank during peak flow events in order to reduce the peak flow coming in to Kuwahee.

Once the flow in the collection system subsides and the operators are ready to accept additional flow at the treatment plant, the controls are set to allow the tank to pump water back into the system at a controlled rate within the capacity of the system and treatment plant.

How long had KUB owned the manufactured gas plant site?

Anthony Crist: The site was actually one of the original properties of the Knoxville Gas Light Company, which later became part of the Knoxville

BEFORE: Photographic renderings from the schematic design phase were utilized to demonstrate to the owner and the public how the finished wastewater storage facility would look. AFTER: Despite the challenges created by the bisecting road and the site’s environmental condition, the project was completed in advance of the EPA mandated deadline and within the budget.

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Constitutes in the soil and groundwater present at the site can degrade PVC, butyl rubber, and other plastic and rubber materials typically employed on a wastewater project. This necessitated the use of alternate construction materials. Site preparation required the use of an exclusion zone for regulated access. Only 40-hour OSHA HAZWOPR trained workers were allowed within the exclusion zone.

Continuous air monitoring for worker safety was required in and around the perimeter of the exclusion zone, protective disposable outer clothing was required and all vehicles and equipment leaving the exclusion zone had to be cleaned by wash-down procedures to prevent migration of the materials offsite.

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JUDGES’ COMMENTS

“...applause for contextsensitive approach.”

Utilities Board. From the turn of the century until around 1960, it was burning coal under controlled conditions and collecting the gas to make coal gas at the manufactured gas facility; a common practice throughout the United States until the 1950s when natural gas started being piped up from the Gulf of Mexico and distributed throughout the country.

What is a brownfield?

Anthony: A brownfield is a piece of land that’s been blighted or somehow made unusable by industrial activity.

It needs cleanup, like removal of old dilapidated structures or, in this case, environmental contaminants from the soil and groundwater. KUB had already committed to restoring this site to beneficial use which was part of the decision to use this site for the storage facility.

What was done with the excavated soil?

Craig: Excavated soils were transported to an approved disposal facility and disposed in accordance with

state regulations. Groundwater was pumped from the excavated area and treated in an on-site treatment facility, then discharged into the sanitary sewer system.

features, landscaping and secure but decorative fencing. Since this tank is above ground, we wanted to make sure the final finish looked consistent with the neighborhood.

Because this land had been unused for some time, what kind of impact did you want the new facility to have on the area?

One of the things we’ve touted all along through this whole group of storage projects is the communityfriendly design. By using odor control and enhancing the appearance, we’re trying to be good neighbors.

Craig: This area of town was somewhat under-developed. Our site was really just a paved parking lot with weeds growing up through the cracks, and an old rickety fence around it.

In 2005, when our team built the first group of tanks, KUB made the decision to consider the appearance of the facilities so they would blend with the neighborhoods.

Architectural concepts we developed for the initial four tanks were carried forward for this project.

What were some of the architectural aspects of the design or elements used to blend in with the community?

Craig: We used brick and cap stone, a curved roof and other architectural

What has the Second Creek facility solved for KUB, the associated systems and the community?

Craig: The Second Creek facility works in conjunction with the Lower Third Creek storage facility to reduce peak wastewater flows to the Kuwahee Wastewater Treatment Plant, which enables the Kuwahee plant to operate more effectively.

The design of the Second Creek facility and associated trunk sewer improvements also solved some capacity and condition issues in the surrounding sewer collection system.

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JUDGES’ COMMENTS

“...environmental remediation really impressive.”

What part of this project will you remember most and/or take with you to the next project?

Anthony: Going forward, we’ll definitely look at the brownfield sites more closely before we build on them.

Even though the borings didn’t show any contamination in the bedrock, it was there, and we hadn’t planned on it. Had we known it was there, we would have chosen compatible materials during design instead of having to research and change materials during construction. Next time, we’ll have a better understanding of the potential effects on construction materials and procedures.

Dale Mosley: It was a tough site to put a pump station and storage tank on. Other sites were considered, but in the overall picture, cleaning up this site and putting a 5.5 million gallon storage tank on a site with height restrictions was a huge accomplishment. Meeting all the goals of the project was pretty tough, but the team pulled together and came up with a great looking storage tank and pump station. Driving past it, you would never know it is a storage tank because it fits right in.

Craig: Despite all of the challenges, we felt like we could meet the EPAimposed June 30, 2011 deadline, and our guys really stepped up to meet deadlines and get the job done. I am proud of the way the team came together to make sure that failure was not an option. 

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The design team made every effort to incorporate aesthetically pleasing features into the project. These features include architecturally enhanced buildings and structures, decorative perimeter fencing with masonry and stone columns, landscaping and grassing.

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ARCHITEC TURE

ENGINEERING

INTERIORS

PLANNING

Gresham, Smith and Partners provides design and consulting solutions for the built environment that contribute to the success of national and international clients. For more than 40 years, GS&P has focused on enhancing quality of life and sustainability within communities. GS&P consists of industry-leading professionals practicing architecture and engineering design as well as scientists and highly specialized planning and strategic consultants in Aviation, Corporate and Urban Design, Environmental Compliance, Healthcare, Industrial, Land Planning, Transportation and Water Services. GS&P consistently ranks among the top architecture and engineering firms in the United States.

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Š Gresham, Smith and Partners 2011