Waynesville Wastewater Treatment Facility
The City of Waynesville owns and operates the Waynesville Wastewater Treatment Facility (MO-0094161). The Waynesville WWTF was constructed in 1979 and has seen several improvements over the past 30-years, including the addition of an equalization basin, sea wall for flood protection, and aerobic digesters for sludge processing and handling. However, most of the equipment related to the pretreatment, secondary treatment and disinfection processes were original to the plant and had exceeded their intended design life. Operational problems, such as the presence of bulking sludge, were routinely experienced, which served to reduce the efficiency of the treatment facility. Finally, the newly released draft operating permit for the facility required the elimination of the existing equalization basin outfall. Improvements to the WWTF were required to allow for optimal operations, to eliminate operational problems that are currently experienced and to bring the plant in compliance with government mandates.
The Waynesville WWTF Improvements project involved the development of plans to eliminate operation problems currently observed at the plant. A new fine screen was implemented at the plant headworks to eliminate coarse solid accumulation in the waste sludge. A new secondary clarifier was proposed to increase the solids settling capability of the plant and to eliminate solids transmission to the chlorine contact chamber. New RAS/WAS pumps and automated controls were implemented to provide the operator with greater control and protection from flooding in the subterranean sludge pumping pit.
In an effort to address discharges from the existing equalization basin outfall, a multi-faceted plan was implemented, which focused on the reduction of I&I and its impacts at the WWTF. First, a new equalization basin was designed, which effectively increase the total peak storage capacity at the plant by 267%. Secondly, sanitary sewer collection system rehabilitation and repair projects were recommended for the oldest regions of the collection system which were designated as high needs areas during a sanitary sewer evaluation study performed in the area earlier this year.