San Ysidro WWTP - Secondary Treatment Plant in San Ysidro, New Mexico

San Ysidro WWTP is a municipal wastewater treatment plant located in San Ysidro, New Mexico, within Sandoval County. The facility serves a population of approximately 2,090 residents, reflecting a small community in the arid southwestern United States. The plant provides secondary treatment, which is the standard biological treatment process required under the U.S. Clean Water Act for municipal wastewater. With a designed capacity of 757.08 cubic meters per day, the plant operates at a scale appropriate for its small service population. The facility is regulated under the National Pollutant Discharge Elimination System (NPDES) permit program, administered by the New Mexico Environment Department. The treated effluent is discharged into the local watershed, which ultimately drains into the Rio Grande, a major river system in the region. The Rio Grande flows south through New Mexico and Texas, supporting diverse aquatic habitats and agricultural water supplies before reaching the Gulf of Mexico. The plant's operations help protect water quality in this ecologically significant river basin.

The plant discharges into the Rio Grande watershed, which flows through arid landscapes and supports critical riparian habitats. The Rio Grande is a vital water source for communities, agriculture, and wildlife in New Mexico and Texas. Downstream, the river feeds into the Gulf of Mexico, contributing to estuarine ecosystems. The plant's secondary treatment helps reduce nutrient and organic pollutant loads, protecting aquatic life in this sensitive desert river system.