Central Marin San Agency WWTF - San Rafael, California Wastewater Treatment Plant

Central Marin San Agency WWTF is a wastewater treatment facility located in San Rafael, Marin County, California, United States. The plant serves a population of approximately 114,000 people, making it a medium-to-large agglomeration under US regulatory standards. It is situated near the San Francisco Bay, a major estuarine environment. As a US facility, the plant operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permits issued by the California State Water Resources Control Board or the San Francisco Bay Regional Water Quality Control Board. For a plant serving over 100,000 people, secondary treatment is typically required, with additional nutrient removal in sensitive areas like the San Francisco Bay. The treated effluent is discharged into the San Francisco Bay, which is part of the larger San Francisco Bay-Delta estuary. This water body supports diverse aquatic life, including fish, birds, and marine mammals, and is an important ecological and economic resource for the region. The plant's discharge must comply with strict water quality standards to protect the bay's health.

The plant discharges into the San Francisco Bay, a large estuary that connects to the Pacific Ocean via the Golden Gate. The bay supports a rich ecosystem, including migratory birds, fish species like salmon and sturgeon, and marine mammals. The plant's operations are critical for maintaining water quality in this ecologically sensitive area, which faces challenges from urban runoff and industrial pollution.