Arnett WWT Wastewater Treatment Plant, Ellis County, Oklahoma

Arnett WWT is a municipal wastewater treatment facility located in Ellis County, Oklahoma, United States. It serves a small population of 520 residents, reflecting its role in a rural community. The plant is situated in the central Great Plains region, characterized by semi-arid climate and agricultural land use. The plant provides secondary treatment, which is the standard level required by the US Clean Water Act for municipal wastewater. Secondary treatment typically involves biological processes to remove organic matter and suspended solids. The plant has a designed capacity of 264.98 thousand cubic meters per year, and its current discharge volume matches that figure, indicating full utilization. As a US facility, it operates under a National Pollutant Discharge Elimination System (NPDES) permit issued by the Oklahoma Department of Environmental Quality, which sets effluent limits to protect water quality. The treated effluent is discharged into a local water body, likely a tributary of the North Canadian River or the Washita River, both part of the Arkansas-Red River Basin. This basin ultimately drains into the Mississippi River and the Gulf of Mexico. The plant's discharge supports local aquatic life and downstream water quality in a region where water resources are critical for agriculture and ecosystems.

The plant discharges into a local stream within the Arkansas-Red River Basin, which flows into the Mississippi River and eventually the Gulf of Mexico. The surrounding watershed is primarily agricultural, and the plant's effluent must meet state water quality standards to protect downstream aquatic habitats, including fish and macroinvertebrate communities. The semi-arid climate means that maintaining adequate streamflow and water quality is essential for both ecological health and human uses such as irrigation.