Amherst County Service Authority reviews draft water and sewer master plan; consultant flags fire-flow, pressure and resiliency gaps

Tom Frederick, an engineer with Pennoni Associates, presented a draft master infrastructure plan to the Amherst County Service Authority Board at its Jan. 21, 2025 meeting, summarizing hydraulic and GIS modeling of the authority's water and wastewater systems and recommending short- and long-term capital and operational changes. Frederick told the board the study converted AutoCAD maps into GIS, inspected vertical assets in March 2024 and calibrated distribution and collection models to test current and future scenarios.

The consultant said the firm set a planning growth target of 0.7% per year for the authority's planning horizon (rather than the lower Weldon Cooper forecast) and that the authority's current treatment and wastewater contracts would accommodate the modeled future demand. "If those development proposals all come through, you would experience a growth in 5 years of 64%," Frederick said, citing six proposed developments the study evaluated. The models were also run with all six projects included to test distribution, collection, fire-flow and treatment impacts.

Why it matters: the plan identifies single-point vulnerabilities that could force public-health actions and affect service during outages, quantifies flushing and storage needs, and estimates multi-million-dollar capital needs that will affect budgeting and bonding decisions.

Key findings and recommendations

- Pressure and resiliency: The study uses a level-of-service benchmark of 30 psi (the state regulatory minimum is 20 psi). Frederick said the study found recurring pressures below 30 psi in several zones (Coolwell, areas near the Prices Store standpipe and dead-end mains), and that some locations could fall below 20 psi during extended outages. "When the pressure is below 20 PSI, there's potential that, back siphoning or backflow of untreated water ... could be contaminated," Frederick said, explaining the VDH rationale for boil-water notices.

- Single-transmission vulnerability: The consultant flagged the 12-inch transmission main leaving the water treatment plant as a single-point failure that, if it ruptured, could drain tanks and force an extended outage requiring a boil-water notice until bacteriological tests cleared the system.

- Fire flow: Hydraulic tests run at maximum-day demand show many hydrants below common benchmarks. Frederick mapped hydrants that model at under 500 gallons per minute (gpm) at 20 psi (red) and those between 500 and 750 gpm (purple). The study recommends prioritizing upgrades in clusters (for example, Galtz Mill Road, the Right Shop zone, Lakeview and portions of Elon). For some locations (Galtz Mill Road) a parallel main would provide flow but could create long dead-ends and water-age problems; the consultant recommended working with the local fire agency on fire-response plans for those areas.

- Water age and flushing: Long dead-end mains cause modeled water ages greater than 10 days in places. Frederick said the model's flushing prescriptions translate to roughly 38,000''10,000 gallons per day (the presentation cited about "somewhere around 50,000 gallons a day") — roughly 5% of treated water — to keep ages below 5 days at those locations. He recommended unidirectional flushing annually and provided site-specific flushing volumes.

- Storage and pressure zones: Noting that standpipes provide limited usable storage if they must remain almost full to maintain pressure, Frederick reported usable-storage estimates (examples from the presentation): the Faulknerville tank (650,000 gallons total, ~152,000 gallons usable under a 30-psi constraint), a Littleton Lane elevated tank (250,000 total, ~213,000 usable) and the Right Shop standpipe (700,000 total, ~98,000 usable at present). Converting the Right Shop tank to ground storage with boosting equipment would restore its full 700,000 gallons as usable capacity. The plan also recommends acquiring two tanks currently at the closed training center (adding ~400,000 gallons) and eventually adding a Coolwell tank (about 500,000 gallons) and an additional tank ("E Line"), which together with other changes could yield about 2.5 million gallons of usable storage.

- North Coolwell zone: To address very low pressures at the North Coolwell / Isaac Walton Road dead-end, the report recommends a booster pump station on the North Coolwell 12-inch main, PRVs, and ultimately a tank set around 1,050 feet above sea level (about 53 feet higher than Faulknerville) to create a higher-pressure zone; the consultant noted the tank could be deferred if variable-frequency drives and a small hydro-pneumatic tank were used at the booster.

- Hydraulic modeling and software: The study provides hydraulic model files developed in Bentley Systems software; Frederick told the board the authority must obtain a Bentley license to operate the models in-house, or it can contract the consultant for updates.

- Advanced metering (AMI): The consultant strongly recommended an AMI (advanced metering infrastructure) program to replace older meters and produce near-real-time consumption data for leak detection and customer alerts. Frederick said AMI helps identify continuous night flow (a likely leak) and reduces uncertainty in non-revenue-water calculations.

- Non-revenue water benchmark: The study estimated Amherst County Service Authority's non-revenue water at just under 20% and cited American Water Works Association benchmarks: 15% as a shorter-term goal and below 10% as an excellent long-term target. "I would suggest 15% as a shorter term goal," Frederick said.

Wastewater findings

- Package plants: The report compared rehabilitating two package wastewater plants to eliminating them and pumping to the trunk system. Estimated construction costs given in the presentation were roughly $300,000+ to rehabilitate the plants versus about $1.4 million to eliminate them by installing lift/pump stations and piping. The consultant recommended rehabilitating the plants at this time, noting rehabilitation was the less costly option under current conditions.

- Collection system: The wastewater model (dry- and wet-weather scenarios) showed adequate pipe capacity across the system, including the modeled future developments, though the firm recommended an inflow and infiltration study (flow meters and rain gauges) to find any localized wet-weather inflow, and regular closed-circuit-television inspection of gravity mains to prioritize repairs.

- Williams Creek pump station: The presentation highlighted flood risk and the need to protect electrical equipment at Williams Creek (which pumps across the James River to the Lynchburg Regional Facility) and recommended an on-site generator and flow meter for resiliency and operational monitoring.

Costs, timelines and prioritization

Frederick presented a summary of capital alternatives and a combined short- and long-term conceptual cost in the tens of millions of dollars. During discussion board members and staff referenced a range of figures presented in the slides (one slide summarized about $27 million; later combined short- and long-term items were discussed in the range of about $36 million). Frederick said the report separates short-term (roughly a five-year planning horizon) and long-term items (20'30 years) but did not assign exact years, noting uncertainty in growth timing.

Board questions, next steps and staff direction

Board members pressed the consultant on fire-flow capacity for larger commercial and industrial properties along U.S. 29 and on prioritization of projects and estimated costs. Board member Martin noted the authority's six proposed developments would add roughly 5,100 housing units (about 2.3 persons per unit was used in the presentation), which could equate to roughly 11,000 new residents if built; Frederick replied the study ran scenarios that assumed all six projects and concluded the distribution and treatment systems could be made adequate with the recommended improvements.

Tim Castillo, director of the Amherst County Service Authority, told the board: "From from this, I will be bringing forth a recommendation at our February meeting to adopt this master infrastructure master plan with comments being addressed from our meeting here today." Castillo and staff said they will use the study to inform the upcoming capital and financial planning process and to consider use of unspent bond funds.

Actions recorded at the meeting

- The board approved the meeting agenda by voice vote after a motion by Mister Turner (motion text: "approve agenda"); the vote was taken by voice and recorded as approved.

- The board approved a motion to adjourn by voice vote at the meeting's close; motion recorded as approved.

What the plan does not decide

The draft presented is a planning document that recommends specific studies and capital projects; it does not commit the authority to construction or financing. The board did not vote to adopt the plan on Jan. 21; staff will return with a formal adoption recommendation in February and with additional cost details (including an AMI cost estimate the consultant said was forthcoming).

Ending

The draft master infrastructure plan gives Amherst County Service Authority a model-driven roadmap for prioritizing upgrades, improving resiliency and targeting metering and flushing programs. The board will consider a formal adoption recommendation and funding strategy at its February meeting; staff said additional financial analyses (bond/unspent funds and operating impacts) will be integrated into the authority's capital-improvement planning.