Worthington WWTP - Secondary Wastewater Treatment in Worthington, Iowa

Worthington WWTP is a municipal wastewater treatment facility located on 3rd Avenue in Worthington, Dubuque County, Iowa. The plant serves a small population of 361 residents, reflecting the rural character of the community. The facility provides secondary treatment, a standard biological process that removes organic matter and suspended solids. With a designed capacity of 624.59 units and a discharge volume of 548.89 units, the plant operates at a high utilization rate. Under the U.S. Clean Water Act, such plants must comply with National Pollutant Discharge Elimination System (NPDES) permits issued by the Iowa Department of Natural Resources. The treated effluent is discharged into a local waterway that drains into the Maquoketa River watershed, ultimately reaching the Mississippi River. This downstream connection links the plant to the broader Upper Mississippi River basin, a critical ecological corridor for aquatic life and migratory birds.

The plant's discharge enters a tributary of the Maquoketa River, which flows into the Mississippi River near Dubuque. The Mississippi River in this reach supports diverse fish species and provides habitat for migratory waterfowl. The watershed is primarily agricultural, so the plant's nutrient removal helps mitigate downstream eutrophication risks in the Gulf of Mexico hypoxic zone.