Valparaiso STP Wastewater Treatment Plant, Valparaiso, Indiana

Valparaiso STP is a municipal wastewater treatment facility located in Valparaiso, Porter County, Indiana, United States. The plant serves a population of approximately 31,680, placing it in the medium agglomeration category under US regulatory frameworks. As a US facility, Valparaiso STP operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Indiana Department of Environmental Management. For plants of this scale, secondary treatment is typically required, with additional nutrient removal standards applicable in the Great Lakes basin. The plant's treated effluent ultimately drains into the Lake Michigan watershed via the local tributary system. Lake Michigan is a critical freshwater resource supporting diverse aquatic life, recreational activities, and municipal water supplies for millions of people in the region.

Valparaiso STP discharges into the Lake Michigan basin, part of the Great Lakes system, the largest group of freshwater lakes on Earth by total area. The receiving waters support a complex ecosystem including native fish species and migratory birds. The plant's location within 50 km of the coast places it in a sensitive watershed where nutrient loading can contribute to algal blooms and eutrophication in nearshore areas.