Saint Henry WWTP and Sewer System - St. Henry, Ohio Wastewater Treatment

Saint Henry WWTP and Sewer System is a municipal wastewater treatment facility located in St. Henry, Mercer County, Ohio. The plant serves a population of about 4,116 residents, classifying it as a small to medium agglomeration under U.S. regulatory frameworks. Its location in rural western Ohio places it within the Wabash River watershed, which ultimately drains to the Mississippi River system. As a U.S. facility, the plant operates under the Clean Water Act's National Pollutant Discharge Elimination System (NPDES) permit program, administered by the Ohio Environmental Protection Agency. The plant's design and operation must comply with state and federal effluent limitations to protect receiving water quality. The treated effluent from Saint Henry WWTP likely discharges to a local tributary of the Wabash River, which flows southwest into the Ohio River and then to the Mississippi River. This watershed supports diverse aquatic life and provides drinking water for downstream communities. The plant's performance is critical for maintaining water quality in this agriculturally intensive region of Ohio.

Saint Henry WWTP discharges into the Wabash River basin, a major tributary of the Ohio River. The Wabash River flows through agricultural and rural areas, supporting fish populations and migratory birds. Downstream, the Ohio River merges with the Mississippi, impacting the Gulf of Mexico ecosystem. The plant's nutrient removal is important to prevent algal blooms in this sensitive watershed.