Engineer outlines $17M, 20-year plan to upgrade Skowhegan wastewater plant; sludge processing flagged as highest near-term cost driver

Olver Associates senior process engineer Bill Olver told the Skowhegan Select Board on June 23 that the town’s wastewater treatment plant—built in 1973 and last rebuilt in sections—needs phased upgrades and substantial investment to remain reliable and meet emerging permit limits.

“The plant was built in 1973, so it’s 53 years old,” Olver said, summarizing a facilities plan the firm prepared. He described a three-priority approach: immediate repairs and replacements (1–5 years), enhancements to improve efficiency (5–10 years), and longer-term replacements to carry the plant another 20 years.

Why it matters: Olver told the board that aging equipment and limited sludge-handling capacity have put operations at risk and driven large disposal costs. He said the plant currently discharges about 26,000 gallons a day of waste sludge and that existing storage (an 80,000‑gallon tank) provides only two to four days of capacity. “The sludge removal is the number one bill, over $120,000 a year,” Olver said, and recommended investments that would reduce sludge volume by roughly 40% through digestion and improved dewatering.

Key recommendations and near-term priorities - Expand septage receiving capacity to about 50,000 gallons and route septage to the sludge side instead of the water side to preserve treatment capacity. - Add a 24‑ft gravity thickener for primary sludge storage and a properly sized sludge digester (Olver suggested ~300,000 gallons) to allow multi‑day digestion and reduce hauling costs. - Replace the existing belt filter press (installed 2007) with dual screw presses (or similar modern equipment) to increase solids concentration and provide redundancy. - Repair corroded concrete, clarifier drives and splitter boxes to ensure even flow distribution between tanks and avoid underperformance.

Costs and phasing: Olver estimated the priority-one package—addressing the most urgent deficiencies, thickener, septage improvements, concrete repairs and electrical/instrumentation work—at roughly $17 million in 2026 dollars, and said costs are volatile (an approximate 5% escalation per year). He emphasized phased work and pursuing multiple funding sources: DEP/Clean Water SRF, USDA Rural Development, NBRC, FEMA for flood work, and congressional/community project funding.

Permit and regulatory context: Olver noted that the plant’s new permit already requires phosphorus monitoring and that nutrient limits (nitrogen, phosphorus) are “on the horizon” in many receiving waters. He advised designing upgrades with nutrient removal flexibility in mind so the town can meet future DEP and EPA limits without an expensive overhaul later.

Board discussion and next steps: Board members asked about staging work so the plant can remain online during construction and about aligning grant funding windows. Olver and interim town manager Donnis Zalewski said contractors commonly work on live plants by keeping one clarifier or reactor online while working on another and by phasing construction. The board requested the facilities plan be used as the basis for funding applications and to prioritize shovel‑ready elements.

The presentation and discussion concluded with Olver urging the town to begin grant applications promptly to avoid higher future costs.

Ending: The board did not take a formal vote on capital funding that night; members directed staff to use the Olver report as a fundraising and planning basis and to return with recommended next steps for design and SRF/grant applications.