Wastewater Treatment Plant

City of Farmington, Missouri

The population of the City of Farmington has grown to the point that their average daily flow exceeded their wastewater treatment plant capacity. Horner & Shifrin was selected to complete the preliminary engineering report.


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.


Project Scope


Project Components



Site Size

300,000 gallon clarifier
1,000,000 gallon filter structure


Farmington, Missouri

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