Middletown WWTP and Sewer System - Excello, Ohio Wastewater Treatment

Middletown WWTP and Sewer System is a municipal wastewater treatment facility located on Oxford State Road in Excello, Ohio, within Butler County. The plant serves a population of around 60,000 residents, placing it in the medium-to-large agglomeration category for U.S. wastewater infrastructure. As a U.S. facility, the plant operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Ohio Environmental Protection Agency. For a plant of this scale, secondary treatment is the minimum standard, with potential for additional nutrient removal depending on the receiving water body's sensitivity. The plant's treated effluent is discharged into the Great Miami River watershed, which flows southwest to the Ohio River, then to the Mississippi River and ultimately the Gulf of Mexico. This drainage path supports diverse aquatic life and provides water for downstream communities and agriculture.

The plant discharges into the Great Miami River basin, which drains into the Ohio River and then the Mississippi River, reaching the Gulf of Mexico. The watershed supports a variety of fish and wildlife, and the plant's nutrient removal performance is important for preventing downstream algal blooms in the Gulf.