The City of Farmington selected a design team led by Horner & Shifrin to complete the preliminary engineering report. Population and flow projections were prepared, and preliminary alternatives were developed in detail. A major aspect of this project was pending new effluent limits. This plant discharges to a tributary of the St. Francis River, so water quality issues, now and in the future, were a major concern. The low-cost option to meet current proposed effluent criteria was to add a second oxidation ditch in series with the existing ditch.
This project also included providing plans and specifications for modifications to an existing 300,000-gallon capacity primary clarifier and an existing 1,000,000-gallon capacity trickling filter structure to convert these two structures into flow equalization basins.
300,000 gallon clarifier
1,000,000 gallon filter structure