Overview
Mason City STP serves approximately 3,150 residents in Mason County, Illinois. The plant operates under the US Clean Water Act, which mandates secondary treatment for municipal wastewater facilities.
Mason City STP is a municipal wastewater treatment plant located in Mason County, Illinois, serving a population of about 3,150. The facility is part of the state's wastewater infrastructure, handling domestic sewage from the local community. As a small-scale plant, it plays a key role in protecting public health and local water quality. Under the US Clean Water Act, municipal wastewater treatment plants are required to meet secondary treatment standards, which typically involve biological processes to reduce organic matter and suspended solids. Facilities of this size in Illinois are regulated by the Illinois Environmental Protection Agency (IEPA) through National Pollutant Discharge Elimination System (NPDES) permits. These permits set effluent limits to ensure compliance with water quality standards. The plant's treated effluent is discharged into a receiving water body within the Illinois River basin, which ultimately flows into the Mississippi River. The downstream environment supports diverse aquatic life and is an important migratory corridor for fish and birds. Proper treatment at this plant helps maintain the ecological health of these waterways.
Environmental context
Mason City STP discharges into a tributary of the Illinois River, which flows into the Mississippi River and eventually the Gulf of Mexico. The Illinois River basin supports a variety of aquatic species and provides critical habitat for migratory birds. The plant's treatment helps reduce nutrient and pollutant loads, protecting downstream water quality and the ecological balance of the river system.
Frequently asked questions
Mason City STP is located at 700N in Mason County, Illinois, United States.
The plant serves approximately 3,150 residents in the Mason County area.
The plant discharges treated effluent into a local waterway that is part of the Illinois River basin, which flows into the Mississippi River.
As a US municipal wastewater plant, Mason City STP operates under the Clean Water Act and is regulated by the Illinois Environmental Protection Agency through an NPDES permit, which sets effluent limits to protect water quality.
Plants of this size typically use secondary treatment, such as activated sludge or lagoon systems, to meet EPA standards for reducing organic matter and suspended solids before discharge.
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