Lower Moosa Canyon WRF | San Diego County, California Wastewater Treatment Plant

Lower Moosa Canyon WRF is a wastewater treatment facility located in San Diego County, California, serving a population of approximately 2,100 residents. The plant is situated in the inland region of the county, away from the immediate coastal zone, and is part of the broader municipal wastewater infrastructure managed by local authorities. With a designed capacity of 1.00 million gallons per day, the plant is sized for a small community. Under the U.S. Clean Water Act, facilities of this scale are typically required to meet secondary treatment standards through National Pollutant Discharge Elimination System (NPDES) permits issued by the California State Water Resources Control Board. These permits ensure that treated effluent meets water quality standards before discharge. The plant's treated effluent likely discharges to a local watercourse that drains into the San Luis Rey River or a tributary, eventually reaching the Pacific Ocean. The facility plays a role in protecting downstream aquatic habitats and maintaining water quality in the region's semi-arid environment.

The plant is located in the San Luis Rey River watershed, which drains from the inland mountains to the Pacific Ocean near Oceanside. The river supports riparian habitats and is used for groundwater recharge and agricultural supply. Downstream, the estuary at the river mouth provides critical habitat for migratory birds and fish species. Protecting water quality in this watershed is important for both ecological health and regional water resources.