Garnavillo WWTP - Secondary Treatment Plant in Garnavillo, Iowa

Garnavillo WWTP is a municipal wastewater treatment facility located in Garnavillo, Clayton County, Iowa. Serving a population of 727, the plant provides secondary treatment to meet state and federal water quality standards. The plant operates under the U.S. Clean Water Act, which requires secondary treatment for municipal wastewater. With a designed capacity of 734.37 thousand gallons per day and an average discharge volume of 681.37 thousand gallons per day, it operates at high capacity utilization. The treatment process is typical for small communities in the Midwest. Treated effluent is discharged to local streams that drain into the Mississippi River basin, supporting downstream aquatic ecosystems. The plant's performance is regulated through the National Pollutant Discharge Elimination System (NPDES) permit program, ensuring protection of water quality in the region.

The plant discharges into tributaries of the Mississippi River, which flows south to the Gulf of Mexico. The local watershed supports diverse aquatic life and is part of the Upper Mississippi River basin, an important ecological corridor for fish and migratory birds. Proper wastewater treatment helps maintain water quality in this agriculturally intensive region.