VIOLA STP - Secondary Wastewater Treatment Plant in Viola, Illinois

VIOLA STP is a municipal wastewater treatment plant located in Viola, Mercer County, Illinois. The facility serves a small community of about 1,067 people, providing essential sanitation services to the area. As a secondary treatment plant, it meets the standard requirements for organic matter and suspended solids removal under the U.S. Clean Water Act. The plant operates with a designed capacity of 416.39 thousand cubic meters per year and currently discharges 264.98 thousand cubic meters annually, indicating available treatment capacity. Secondary treatment typically involves biological processes such as activated sludge or trickling filters, followed by clarification and disinfection. The plant is regulated under the National Pollutant Discharge Elimination System (NPDES) permit program, which sets effluent limits to protect water quality. The treated effluent from VIOLA STP is discharged into a local water body, likely a tributary of the Mississippi River basin. The plant's inland location and small population served reduce its environmental footprint, but proper operation remains important for maintaining local stream health and downstream water quality in the Mississippi River system.

VIOLA STP discharges treated wastewater into a local receiving water body within the Mississippi River basin. The plant is located in rural western Illinois, where the watershed supports agricultural drainage and small streams that flow into the Mississippi River. The Mississippi River downstream provides critical habitat for diverse aquatic species, including freshwater mussels and migratory fish. Maintaining effective secondary treatment helps protect these ecosystems from nutrient enrichment and pathogen contamination.