Cottonwood WWTP - Secondary Treatment Plant in Shasta County, California

Cottonwood WWTP is a municipal wastewater treatment facility located in Shasta County, California, United States. The plant serves a population of approximately 2,960 residents, operating as a secondary treatment facility under the regulatory framework of the US Clean Water Act. The plant has a designed capacity of 1,627.72 thousand cubic meters per year and currently discharges 984.21 thousand cubic meters of treated wastewater annually. As a secondary treatment plant, it meets the standard requirements for biological treatment of organic matter and suspended solids, as mandated by the US EPA for facilities of this scale. The treated effluent is discharged into the local watershed, which ultimately drains into the Sacramento River system. This river is a critical water resource for California's Central Valley, supporting agricultural irrigation, aquatic habitats, and downstream communities. The plant's operations contribute to protecting water quality in this important regional basin.

Cottonwood WWTP discharges into the Sacramento River watershed, which flows south through California's Central Valley to the Sacramento-San Joaquin Delta and ultimately into San Francisco Bay. The watershed supports diverse aquatic life, including salmon and steelhead trout, and provides water for extensive agricultural and urban uses. The plant's secondary treatment helps reduce nutrient and organic pollutant loads, protecting downstream water quality and ecosystem health.