Royal City S_T FAC Wastewater Treatment Plant, Royal City, Washington

Royal City S_T FAC is a municipal wastewater treatment facility located in Royal City, Grant County, Washington. The plant serves a small population of 1,815 residents and is part of the region's infrastructure for managing domestic wastewater in an agricultural and rural setting. The plant provides secondary treatment, which is the standard level required by the US Clean Water Act for municipal facilities. Its designed capacity is 946.35 megaliters per year, matching the reported discharge volume, indicating full utilization. As a small-scale plant, it is subject to National Pollutant Discharge Elimination System (NPDES) permitting, which sets effluent limits to protect water quality. The treated effluent is discharged into the local watershed, which ultimately drains into the Columbia River basin. The Columbia River is a major waterway in the Pacific Northwest, supporting diverse aquatic life and providing water for irrigation, recreation, and hydropower. The plant's operations help protect downstream water quality in this ecologically significant river system.

The plant discharges into the Columbia River basin, a vast watershed that flows through Washington and Oregon before reaching the Pacific Ocean. The Columbia River supports salmon runs, steelhead, and other native fish species, making water quality management critical. The plant's secondary treatment reduces organic pollutants and suspended solids, helping to maintain the river's ecological health.