ELBE STP - Secondary Wastewater Treatment Plant in Elbe, Washington

ELBE STP is a municipal wastewater treatment plant located in Elbe, a small community in Pierce County, Washington, United States. The plant serves a population of 176 residents, reflecting its role in a rural, inland setting within the Pacific Northwest region. The plant provides secondary treatment, which is the standard level required under the U.S. Clean Water Act for municipal wastewater facilities. Secondary treatment typically involves biological processes to remove organic matter and suspended solids. The plant's designed capacity is 37.85 megaliters, with an annual discharge volume of 30.28 megaliters, indicating it operates below its full capacity. The treated effluent is discharged into a local water body that ultimately drains into the Nisqually River watershed, which flows into Puget Sound. This watershed supports diverse aquatic life, including salmon runs, and the plant's operations are regulated under the National Pollutant Discharge Elimination System (NPDES) to protect downstream water quality.

ELBE STP discharges into a tributary of the Nisqually River, which flows into Puget Sound, an ecologically significant estuary. The Nisqually River watershed supports critical salmon habitat and diverse wildlife. The plant's secondary treatment helps reduce nutrient and organic pollutant loads, protecting downstream aquatic ecosystems from eutrophication and oxygen depletion.