IRWD Facilities

IRWD is Orange County's largest retail water district, providing water and sewer service to nearly 100,000 homes and businesses throughout the City of Irvine and portions of Tustin, Newport Beach, Costa Mesa, Orange, Lake Forest and unincorporated Orange County. Below are some key facilities in our delivery andtreatment systems.








Baker Water Treatment Plant

The Baker Water Treatment Plant is a joint regional project by five South Orange County water districts, supported by community and business organizations, that provides 28.1 million gallons per day (mgd) drinking water at the site of the former Baker Filtration Plant in the City of Lake Forest.

Deep Aquifer Treatment System

The Deep Aquifer Treatment System purifies drinking water from deep within the Orange County Groundwater Basin. The process removes impurities, left from ancient vegetation in the bedrock, and produces eight million gallons (mgd) of drinking water each day.

Irvine Desalter Project

The Irvine Desalter Project (IDP) consists of five wells located near the I-5 Freeway in Irvine. Salty water is pumped from these wells and sent to the IDP treatment facility. The treatment process removes salts from local groundwater to add to our local drinking water supplies. IDP's purfied water provides 5,1000 acre-feet or 1.6 billion gallons of drinking water, enough for 50,000 people, per year.

El Toro Groundwater Remediation Program

The El Toro Groundwater Remediation Program was initiated when in 1985 trichloroethylene, also known as TCE, was found in portions of the groundwater basin beneath the former El Toro Marine Corps Air Station and central Irvine. TCE is a volatile organic compound, or VOC, that was widely used as a solvent for aircraft cleaning. Prior to the development of stricter environmental regulations in the mid-1970's, it was common to dispose of cleaning solvents by simply rinsing off the aircraft and allowing the runoff to run into the ground. As a result, a one-by-three-mile plume of contamination now extends off the base. The contamination is about 150 feet deep beneath the base and 300-700 feet deep in the community area.

In January 2007, IRWD, the Orange County Water District and the United States Department of the Navy began a joint operation, now called the El Toro Groundwater Remediation Program, designed to clean up the TCE plume. This operation pumps water from the plume of TCE contamination and removes the TCE. The resulting treated water is used for non-drinking purposes only. Each year this program provides 1.3 billion gallons of clean water, enough to irrigate 1,300 acres of landscaping. The cleanup of the plume is expected to take approximately 40 years.

Michelson Water Recycling Plant

The Michelson Water Recycling Plant converts an average of 28 million gallons of sewage each day into recycled water. The water is used for landscape irrigation, industrial uses and toilet flushing. The plant was built in 1961 and is IRWD's primary source of recycled water. A major plant expansion was completed in 2014.

Irvine Lake

Irvine Lake (formerly Santiago Reservoir) was built in 1931 to supply water for agriculture. It was opened to fishing ten years later. Today, IRWD shares ownership of the lake with Serrano Water District. The 700-acre lake holds more than 9 billion gallons of water and is contained by the 810-foot-tall Santiago Dam.

San Joaquin Reservoir

The San Joaquin Reservoir was built in 1966 originally to store drinking water. After a law was passed prohibiting the storage of drinking water in open reservoirs, IRWD converted it to hold recycled water. Located in Newport Coast, this reservoir currently stores nearly a billion gallons of recycled water for future irrigation use.

Los Alisos Water Recycling Plant

The Los Alisos Water Recycling Plant converts an average of seven million gallons of wastewater each day into recycled water. The water is used for landscape irrigation and other non-drinking uses. The plant was built in 1964 and, along with the Michelson Water Recycling Plant, provides the District's recycled water supply.

Wells 21 and 22 Pipelines, Wells and Water Treatment Plant

Wells 21 and 22 Project recovers and treats local impaired groundwater for use in the potable water system. This new source of drinking water helps to satisfy increasing demand for water and serves as a sustainable infrastructure with long-term benefits. The Wells 21 and 22 project produces approximately 6,300 acre-feet per year of potable water for the IRWD service area.

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