Walnut Creek Sewer District Wastewater Treatment Plant, Fairfield County, Ohio

Walnut Creek Sewer District is a wastewater treatment plant located in Fairfield County, Ohio, United States. It serves a small population of 1,430 residents in the Walnut Township area, operating as part of the region's municipal wastewater infrastructure. The plant provides advanced treatment, which goes beyond the secondary treatment required by the US Clean Water Act for facilities of this scale. It has a designed capacity of 685.16 million gallons and treats an annual discharge volume of 473.18 million gallons, indicating operational headroom. The treated effluent is discharged into local waterways that ultimately drain into the Ohio River basin. The plant's advanced treatment helps protect downstream water quality in this ecologically important watershed, which supports diverse aquatic life and recreational uses.

The plant discharges into tributaries of the Ohio River, which flows into the Mississippi River and eventually the Gulf of Mexico. The Ohio River basin is a major ecological corridor supporting fish, mussels, and migratory birds. Advanced treatment reduces nutrient loading, helping to mitigate downstream hypoxia in the Gulf.