Brief Project Description
The existing Warsaw Wastewater Treatment Plant (WWTP) has a permitted design flow of 0.3 MGD. This aerated lagoon process was designed for partial nitrification (ammonia reduction through conversion to nitrate), and does not provide any capability for removing nitrogen or phosphorus. The treatment plant consists of a manually cleaned bar screen, three high density polyethylene (HDPE) lined aeration lagoons, two 20-foot diameter clarifiers, three HDPE lined polishing ponds, a chlorination/dechlorination tank, and a cascade for reaeration. Under a separate but recent project, an effluent pump station, force main and diffuser were installed to relocate the discharge to Totuskey Creek. The solids handling system consists of an aerobic sludge holding tank and four units of sludge drying beds for sludge processing, which are not currently used.
Under the proposal submitted for nutrient removal cost share, the existing process will be replaced with enhanced nutrient removal (ENR) capability. The proposed WWTP will consist of entirely new equipment. The head works will include a 1/4-inch mechanically cleaned fine screen, an aerated grit removal system, an influent magnetic flow meter, and a new head works building. The existing Lagoon No. 1 will be reconfigured for sideline flow equalization, and a new flow diversion vault and flow diversion pump station will be installed to handle wet weather peaks. The biological process will consist of dual 125,000 gallon sequencing batch reactors (SBRs) with an integral 64,000 gallon post-equalization tank, followed by up-flow sand filtration for solids removal, ultraviolet (UV) disinfection, and a new reaeration cascade. A plant waste pump station will return filter backwash, aerobic digester supernatant, sludge filtrate, and plant sewage flows to the influent of the SBR tanks. A metal salt storage and multiple point feed system will be installed for phosphorus removal. A methanol storage and feed system will be constructed for supplemental carbon addition to the SBRs. The solids handling process will include two new 67,000 gallon aerobic digester tanks integral to the SBR structure, and either a sludge dewatering screw press or rotary fan press (at the discretion of the contractor to provide). The dewatering building will be combined with the head works building, and associated solids handling equipment such as pumps will also be constructed. A combined administration and laboratory building will be constructed.
In summary, the new WWTP project will include the following:
- A new administration and operational control center (partially grant eligible)
- Influent head works with fine screen, aerated grit removal, and flow measurement (none of which are grant eligible)
- Flow equalization using existing Lagoon No. 1 (partially grant eligible)
- Installation of two Sequencing Batch Reactors with combined post-equalization structure
- Aerobic solids digestion and either screw press or rotary fan press dewatering (partially grant eligible)
- Metal salt (ferric chloride) storage and feed system for TP removal
- Methanol storage and feed system for supplemental carbon addition to the SBRs
- Tertiary filtration which includes up-flow sand filtration (two filtration cells are grant eligible) and filter bypass capability
- UV disinfection (not grant eligible)
- Effluent post-aeration