Oswego C West Side STP - City of Oswego, New York Wastewater Treatment Plant

Oswego C West Side STP is a municipal wastewater treatment plant located in the City of Oswego, New York, on the southeastern shore of Lake Ontario. The facility serves a population of approximately 15,500 residents, classifying it as a medium-sized agglomeration under U.S. regulatory frameworks. As a plant in New York State, it operates under the U.S. Clean Water Act, administered by the New York State Department of Environmental Conservation (NYSDEC) through the State Pollutant Discharge Elimination System (SPDES). For plants of this scale, secondary treatment is typically required, with additional nutrient controls in sensitive watersheds like the Great Lakes basin. The plant's treated effluent is discharged into Lake Ontario, part of the Great Lakes system that drains via the St. Lawrence River to the Atlantic Ocean. Lake Ontario supports diverse aquatic life, including native fish species and migratory birds, and is a critical freshwater resource for millions of people.

The plant discharges into Lake Ontario, the easternmost Great Lake, which flows into the St. Lawrence River and ultimately to the Atlantic Ocean. The lake supports a complex ecosystem with native fish such as lake trout and walleye, and serves as a major stopover for migratory waterfowl. Nutrient loading from wastewater can contribute to algal blooms, making treatment standards important for lake health.