8.15.23 Sewerability Presentation

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2023 Rural Sewer Capability Study Overview

Urban Growth Management Master Plan Advisory Committee

August 15, 2023

• How topography drives a sewer system layout • 2023 Study methodology – key points

• Potential regulatory obligations

• Committee questions, comments, discussion

RURAL SEWER CAPABILITY 2023
AGENDA
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• 14 areas included in study.

• Topography influences the menu of alternatives in some areas.

• The drainage engineer perspective: contours and catchments define service area boundaries – not property lines and roads.

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HYPOTHETICAL DRAINAGE EXAMPLE

• Sewer systems operate best like a bathtub – the outlet (drain) is the treatment plant.

• If you divide the bathtub into parts with no drain, you have to pump to a drain.

• Fayette County has eight main bathtubs (and multiple smaller ones) and only two drains (treatment plants).

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Study Methodology Highlights

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RURAL SERVICE AREA (RSA) LIST

RURAL SEWER CAPABILITY 2023 7 RSA # RSA NAME GROSS ACRES 1 Lower South Elkhorn 1,219 2 Mint Lane 572 3 Man O War 375 4 Old Frankfort Pike 1,682 5 Iron Works Pike 6,909 6 Royster Road 2,354 7 Avon / I-64 4,046 8 Avon / I-64 (Extension) 10,165 9 Chilesburg / Walnut Hill 124 10 Athens - Boonesboro 298 11 Lower East Hickman 4,622 12 Boonesboro Manor 504 13 Canebrake 188 14 Blue Sky 90

Gross Acres Verses Developable Acres

2There are no known Special Natural Protection Areas in the study areas

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DEVELOPABLE NOT DEVELOPABLE FLOW CONTRIBUTION Floodplains X 0 Parks X 0 PDR Parcels X 0 Rural Residential Parcels1 X 2 people per acre Rural Settlements X 2 people per acre Special Natural Protection Areas2 X 0 Agriculture X 15 people per acre
1Rural Residential Parcels are parcels 10 acres or less and zoned residential
9 RSA # RSA NAME GROSS ACRES DEVELOPABLE ACRES PERCENT REDUCTION 1 Lower South Elkhorn 1,219 794 34.9 2 Mint Lane 572 537 6.1 3 Man O War 375 336 10.4 4 Old Frankfort Pike 1,682 764 54.6 5 Iron Works Pike 6,909 2,093 69.7 6 Royster Road 2,354 1,921 18.4 7 Avon / I-64 4,046 2,405 40.6 8 Avon / I-64 (Extension) 10,165 6,026 40.7 9 Chilesburg / Walnut Hill 124 68 45.2 10 Athens - Boonesboro 298 273 8.4 11 Lower East Hickman 4,622 2,821 39.0 12 Booneboro Manor 504 428 15.1 13 Canebrake 188 149 20.7 14 Blue Sky 90 50 44.4
RURAL SEWER CAPABILITY 2023

Study Approach Capital Cost

• Methodology – proprietary costing tool developed by Hazen

• Same costing tool used to project Consent Decree capital construction costs

• Estimates do not include design fees, property acquisition costs and other administrative costs (legal, project management, inspection, etc.)

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Study Approach - Capital Cost

• Capital cost estimates were developed for all “plausible” alternatives within each study area. Those cost estimates were combined with the developable acres estimate to make a comparative “Cost per Developable Acre” metric.

• Metric serves as a basis of cost / benefit but is not absolute because:

• Area geometries may be adjusted in a way that impacts the amount of developable acres and/or the cost to serve the adjusted acre total.

• Some alternatives require more LFUCG existing customer cost participation than others. The fiscal impact of those outcomes have not been fully evaluated.

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LFUCG Customer Cost Example

• Downstream infrastructure in an Expansion Area could potentially serve existing upstream customers.

• In most cases, it should, to avoid system inefficiencies.

• Cost of the new downstream infrastructure should be flow proportional:

• X% of flow existing customers / Y% of flow new development.

• X% of cost existing customers / Y% of cost new development.

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RURAL SEWER CAPABILITY 2023 13 Easy Example – Existing LFUCG Customers Served by Expansion Infrastructure

OTHER STUDY METHODOLOGIES OF NOTE

• Evaluated downstream controls for RSAs are either:

• Pump stations, or

• Pump stations with storage tanks, or

• A wastewater treatment plant

• Downstream controls are not a collection of small pumping stations dedicated to specific parcels or developments.

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OTHER STUDY METHODOLOGIES OF NOTE

Wastewater infrastructure may be located within parcels that participated in the PDR Program if it maximizes the efficiency for conveying flows in an RSA.

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OTHER STUDY METHODOLOGIES OF NOTE

• As any sanitary sewer system ages, wet weather flows increase due to Inflow and Infiltration (I/I). The study considers this unavoidable circumstance in its future flow projections and costs.

• In terms of infrastructure, the study assumes that no I/I is directly conveyed to a treatment plant, instead it is stored at the pump station site until downstream capacity is restored.

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REGULATORY

IMPACTS OF EXPANSION

New Wastewater Treatment Plant Scenario

Estimated time – 15 years

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REGULATORY IMPACTS OF EXPANSION

Existing Wastewater Treatment Plant Scenario

Estimated time – 5 years

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REGULATORY IMPACTS OF EXPANSION Population Growth

• If growth plans identify the need to serve more than 30 percent additional equivalent population, a new Facility Plan must be submitted and approved by the state.

• Lexington’s 30% threshold: 30% of 346,007 = 103,802.

• At a projected density of 15 ppl per acre, developable acreage trigger is 6,920 acres. At 21 ppl per acre, developable acreage trigger is 4,943 acres.

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REGULATORY IMPACTS OF EXPANSION Treatment Plant Capacity

Kentucky Administrative Regulations obligate utilities to develop and implement capacity management plans when plant capacity reaches 95%.

Where you expand and where the sewage goes impacts this trigger.

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Rated Capacity (MGD) 30 33.8 95% Capacity Trigger (MGD) 28.5 32.11 Current 3-Year Annual Avg. (MGD) 20.5 19.2 Available Capacity Before Trigger (MGD) 8.0 11.6
TOWN BRANCH WEST HICKMAN

Committee Questions, Comments and Discussion on How to Make Next Meeting Productive

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