DANVILLE STL Wastewater Treatment Plant, Des Moines County, Iowa

DANVILLE STL is a municipal wastewater treatment plant located in Des Moines County, Iowa, United States. The facility serves a small population of 926 residents, reflecting its role in a rural or small-town setting within the state. The plant provides secondary treatment, which is the standard level required under the U.S. Clean Water Act for municipal wastewater facilities. With a designed capacity of 757.08 cubic meters per day and an average daily discharge of 378.54 cubic meters, the plant operates well within its capacity. As a U.S. facility, it is subject to National Pollutant Discharge Elimination System (NPDES) permitting, which sets effluent limits to protect water quality. The treated effluent is discharged into a local receiving water body, which ultimately drains into the Mississippi River basin. This watershed supports diverse aquatic life and is a critical resource for communities and ecosystems in the Midwest. The plant's operation helps maintain water quality in the region's streams and rivers.

The plant discharges into a water body that is part of the Mississippi River watershed, one of the largest drainage basins in North America. The downstream environment includes the Mississippi River, which provides habitat for numerous fish and migratory bird species. The plant's secondary treatment helps reduce nutrient and pollutant loads, supporting the ecological health of the river system.