Moses Lake STP - Wastewater Treatment Plant in Moses Lake, Washington

Moses Lake STP is a municipal wastewater treatment facility located in Moses Lake, Washington, serving a population of about 10,820. The plant is situated in Grant County, east of the Cascade Range, in a semi-arid region. As a medium-sized agglomeration, it plays a key role in managing wastewater for the local community. The plant operates under the U.S. Clean Water Act, which requires secondary treatment for municipal facilities of this scale. The regulatory framework ensures that effluent meets federal and state standards to protect receiving waters. Typical facilities of this size employ biological treatment processes. The treated effluent is discharged into the Moses Lake watershed, which is part of the larger Columbia River basin. Moses Lake is a natural lake that drains via the Potholes Reservoir and Crab Creek into the Columbia River. The downstream environment supports diverse aquatic life, including salmon and trout species, and is important for regional irrigation and recreation.

The plant discharges into Moses Lake, a natural lake in central Washington that is part of the Columbia River basin. Water from Moses Lake flows through the Potholes Reservoir and Crab Creek before reaching the Columbia River, which ultimately drains into the Pacific Ocean. The watershed supports a variety of fish species, including salmon and steelhead, and is used for agricultural irrigation. Protecting water quality in this system is important for both ecological health and human uses.