Forks Treat STP - Secondary Wastewater Treatment in Forks, Washington

Forks Treat STP is a municipal wastewater treatment facility located in Forks, Washington, a small city on the Olympic Peninsula in Clallam County. The plant serves a population of around 3,120 residents and operates under the regulatory framework of the U.S. Clean Water Act, which requires secondary treatment for municipal discharges. The plant provides secondary treatment, a standard biological process that removes organic matter and suspended solids. With a designed capacity of 1,324.89 thousand cubic meters per year and an average discharge volume of 529.96 thousand cubic meters per year, the facility operates well within its capacity. As a U.S. plant, it is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Washington State Department of Ecology, ensuring compliance with water quality standards. The treated effluent is discharged into the local watershed, which drains into the Pacific Ocean via the Quillayute River system. The Olympic Peninsula is ecologically significant, supporting diverse aquatic life and salmon runs. The plant's location more than 10 km from the coast reduces direct marine impact, but its discharge contributes to the freshwater ecosystem that ultimately reaches the ocean.

The plant discharges into the Quillayute River basin, which flows through temperate rainforests of the Olympic Peninsula before reaching the Pacific Ocean. This watershed supports critical habitat for Pacific salmon and steelhead trout, making water quality management essential for downstream ecological health. The region's high rainfall and forested terrain influence runoff and treatment demands.