Environmental Engineering

Erie Water Treatment Plant Backwash Solids Handling

JVA and Fischer Construction teamed for the Design Build of the Town of Erie WTP Solids Handling Project. The $4.2M project included solids pumping, solids thickening and storage tanks, dewatering equipment, a bulk PAC silo and dosing equipment, and the addition of sodium permanganate as a preoxidant. The solids handling facility is sized to handle both the current 10 MGD capacity and a future expansion to 17MGD. The Town of Erie has historically discharged WTP solids to the sanitary sewer system which caused issues with the biosolids handling at the WWTP due to PAC and other chemicals found in the residuals.

Mechanical dewatering with a centrifuge was selected to minimize footprint, chemical usage, and maximize dewatered solids percent. Value engineering through the design-build process led to reuse of the existing building foundation and repurposing of a tank, and construction of a new building over the existing foundation to house the new equipment. Project savings from these design decisions enabled the purchase of a bulk PAC silo instead of relocation and reuse of a smaller, existing super-sack PAC system significantly reducing material handling and storage requirements. Savings also enabled the Town to add $0.6M of clearwell improvements to improve baffling and add operational flexibility to run the clearwells in series or parallel, as well as upgrade the polymer dosing system with an aging tank. The facility is one of the only water treatment plants dewatering residuals in the State of Colorado.

Location: Erie, CO

Budget: $4.2M