County outlines timeline and fixes for Albany County Water Purification Plant; mixing-system replacement and odor study planned

Albany County staff provided a detailed update to the Conservation, Sustainability and Green Initiative Committee on March 24 about a multi-year sludge-processing improvement project at the Albany County Water Purification Treatment Plant, including the causes of persistent odors, funding sources and a planned schedule to complete design and begin construction.

County staff said the county first requested a modification to a consent order with state regulators in September 2021 and submitted five iterations of a preliminary engineering report (PER) between 2022 and March 14, 2025. "On March 28th of '25, that report and that project was ultimately approved by both DEEC and EFC," a presenter told the committee, allowing the county to progress to engineering design.

Staff outlined a design timeline aimed at completing a basis-of-design report by the end of the current month and submitting full design drawings and specifications by June 19, 2026, with the goal of finishing reviews by Q3 2026. Bidding would follow, with construction expected to begin in early 2027 and continue into 2029. EFC financing is scheduled to close in July; staff said ARPA funds have been used to advance engineering with the expectation that EFC funds and other grants will finance construction.

Officials cited multiple funding sources: ARPA money for engineering, a 0% hardship loan through the Environmental Facilities Corporation (EFC) up to $25 million for 30 years, $25 million from bipartisan infrastructure grants, and pursuit of an additional $25 million in WEIA grant funds for other capital work. Staff said EFC is expected to close a financing package in July.

Committee members and staff discussed why the county moved away from an anaerobic digester approach. Presenters said the initial digester concept evolved between 2016 and 2021; rising sludge volumes, higher-than-expected ammonia loads and regulatory uncertainty around land application and PFAS-related disposal risks changed project metrics and increased estimated capital and operating costs. "Digesters don't treat for PFAS; they can concentrate it," a presenter said, explaining that disposal costs and regulatory risk made the digester approach less attractive.

Staff identified the mixing system in sludge holding tanks as a primary contributor to odors. Mechanical paddle mixers failed (largely as a result of rags and mechanical wear), and a temporary aeration approach increased off-gassing by increasing air contact with hydrogen sulfide. To reduce odors, staff reported operational changes including installing variable-frequency drives on blowers to lower air rates and operating three active tanks as a single volume to keep levels lower. Each tank holds about 300,000 gallons (four tanks provide roughly 1.2 million gallons total), a scale that complicates chemical-treatment pilots and storage of treatment chemicals.

A chemical misting pilot conducted in June–July last year was not effective: vendor dosage estimates were orders of magnitude too small, producing little measured improvement while requiring impractically large amounts of chemical and associated bulk storage permitting. Consequently, the county abandoned that pilot and contracted a consultant to study permanent odor-control alternatives. "They're going to be starting that work probably within the next week or two to essentially look at alternatives for a permanent odor-control system," staff said.

As part of the long-term fix, the county plans to replace mechanical mixers with a large-bubble air mixing system that uses far less air and relies on floor mixing rather than mechanical arms. Staff described a design that reduces blower horsepower and centralizes air supply (a single compressor on the order of 40 horsepower to serve four tanks), which they said should reduce off-gassing and maintenance downtime compared with the old mechanical arms.

Staff also said they are in early discussions with an ozone vendor to pilot treating the headspace of tanks as an interim option if a rental pilot unit is available. The county will pursue parallel tracks: fast-tracking the mixing-system replacement while the odor-control study evaluates permanent options.

Committee members asked which neighborhoods have been affected by odors; staff identified North Albany and areas up into Menands (near Erie Boulevard and Canal Road) as the primary zones. Members urged improved public communication; staff said they had relied in part on state partners for unified messaging but reported new, regular progress meetings with state agencies and region leadership that they expect will accelerate reviews and coordination.

Staff described the project procurement as traditional design–bid–build but said phasing will be used to accelerate the mixing-system work separately from longer-lead items tied to the incinerator. The county said DEEC and EFC have agreed to monthly progress meetings to shorten review cycles and reduce repeated back-and-forth comments during the design review process.

The committee received the presentation, asked questions about interim mitigation and communications, and adjourned after a motion to end the meeting.