Culdesac S_T Facility Wastewater Treatment Plant, Idaho

The Culdesac S_T Facility is a municipal wastewater treatment plant located in Culdesac, Nez Perce County, Idaho, United States. It serves a small population of 380 residents, reflecting the rural character of the area. The plant is situated inland, far from coastal waters, and its operations are part of the local infrastructure managed under state and federal regulations. The facility provides secondary treatment, which is the standard level required by the U.S. Clean Water Act for municipal plants of this scale. Secondary treatment typically involves biological processes to remove organic matter and suspended solids. The plant has a designed capacity of 208.20 volume units and currently discharges 143.85 volume units, indicating it operates below its maximum capacity. The treated effluent is discharged into the local watershed, which ultimately drains into the Clearwater River and then the Snake River, a major tributary of the Columbia River. This water body supports diverse aquatic life and is important for regional ecology. The plant's operations are subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Idaho Department of Environmental Quality, ensuring compliance with water quality standards.

The Culdesac S_T Facility discharges into the local watershed, which flows into the Clearwater River, a key tributary of the Snake River. The Snake River then joins the Columbia River, which empties into the Pacific Ocean. This river system supports salmon and steelhead runs, making water quality management critical for downstream aquatic habitats. The plant's secondary treatment helps reduce pollutant loads, protecting these ecologically sensitive waters.