In order to deal with extreme I/I flows, the City of Wyoming’s wastewater treatment facility (WWTF) is transitioning from a controlled discharge lagoon to a continuous discharge process. Their lagoon size could only handle a certain level of flow due to high I/I flows—the WWTF was discharging multiple times per year which was in violation of their DNR permit.
IIW is currently assisting the City with a lagoon upgrade and headworks improvement project that will allow the WWTF to meet the DNR’s permit levels. The project included construction of a new aerated lagoon and Submerged Attached Growth Reactor (SAGR) System, within the limits of one of the existing non-aerated lagoon cells. Construction of the new lagoon system will involve the removal of sewage sludge, construction of earthen lagoon basins, erection of chemical feed and blower buildings, installation of aeration piping and diffusers, and construction of a SAGR ammonia removal system. The project also includes construction of a chlorine contact basin, flow metering manhole, recirculation pump station, yard piping and manholes, and construction of access roadways. Electrical improvements and discharge piping modifications at the Influent Lift Station that feeds raw wastewater to the WWTF will also be made.
The Wyoming WWTF is the third SAGR System to be permitted by the Iowa DNR. An SAGR Sytem utilizes a fully aerated, clean stone bed for water flow. A mulch layer is used to prevent ice and allow treatment at near freezing temperatures.