REDONDO STP Wastewater Treatment Plant, Federal Way, Washington

REDONDO STP is a municipal wastewater treatment plant located in Federal Way, Washington, within King County. It serves a population of roughly 35,420 people, placing it in the medium-agglomeration category under U.S. regulatory frameworks. The plant is situated near the Puget Sound, a major estuary on the Pacific coast. As a U.S. facility, REDONDO STP operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the Washington State Department of Ecology. For a plant of this scale, secondary treatment is typically required, with additional nutrient controls in sensitive areas like Puget Sound. The plant's designed capacity is 1.00 million gallons per day, indicating it is sized to handle current and near-future flows. The treated effluent from REDONDO STP is discharged into the Puget Sound basin, which ultimately drains to the Pacific Ocean. Puget Sound is a critical ecological resource, supporting diverse marine life including salmon, orcas, and shellfish. The plant's operations are important for protecting water quality in this sensitive estuarine environment.

REDONDO STP discharges into the Puget Sound, a large estuarine system connected to the Pacific Ocean via the Strait of Juan de Fuca. Puget Sound supports a rich ecosystem of fish, marine mammals, and seabirds, and is a vital resource for the region's economy and recreation. The plant's location within a densely populated watershed means its effluent quality directly affects local marine habitats and shellfish harvesting areas.