The Santa Margarita Water District is Orange County’s second-largest water district, providing water and wastewater treatment services to more than 165,000 residents and businesses in Mission Viejo, Rancho Santa Margarita, Coto de Caza, Las Flores, Ladera Ranch, and Talega.

The District is divided into eight improvement districts, that encompass approximately 52,000 acres of land. Improvement districts function as operating units of SMWD, and each improvement district’s facilities are funded with its own bonds, so residents of older neighborhoods don’t have to pay for facilities in new neighborhoods. These districts also allow SMWD to meet the diverse needs of specific service areas, factoring in land use, topography, ownership lines, water supply and wastewater treatment needs.

Where Our Water Comes From

Southern California may be a beautiful place to live, but it’s also heavily populated with few local water sources. Water districts in north Orange County have access to an underground aquifer, which supplies them with about more than half of their water supply. However, with no aquifer to tap in south Orange County, SMWD relies upon other water sources, such as groundwater reuse and water recycling programs, to supply our water.

Nearly all of the District’s water supply is purchased from the Metropolitan Water District of Southern California, which delivers water to the region from Northern California via State Water Project and from the Colorado River via the Colorado River Aqueduct. Water from both sources is purified and tested at the Diemer Filtration Plant in Yorba Linda to make sure it meets federal drinking water standards. Then it is piped to SMWD, and then to you.


SMWD is currently closed

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