Water Supply & Reliability

Water. It’s why Irvine Ranch Water District was created over 60 years ago. The District provides high-quality drinking water to more than 425,000 residents. Water is a vital resource, requiring careful management to ensure the needs of present and future generations are met. Through thoughtful planning and prudent fiscal policies, we cost-effectively manage our water portfolio, while continuing to diversify supplies to enhance future reliability.

Since our inception, we’ve not only delivered water, but also value in all we do for our customers and the region. IRWD is known for its progressive programs. From providing quality water, to diversifying our water portfolio and planning now to ensure future water supplies – we believe in going above and beyond to work efficiently, cost effectively and in an environmentally sensitive way.

delta waterway IRWD has a diverse water supply portfolio to keep rates as low as possible. Everyone’s heard the adage “don’t put all your eggs in one basket.” In the water business that means not relying on just one source of water. IRWD is committed to providing a highly reliable water service. We work hard to ensure our customers have diverse sources of water for increased reliability now and in the future.

Some parts of Orange County are 100% dependent on water from outside this area. Not so at IRWD. We've worked hard to decrease our dependence on costly imported drinking water. Finding new sources of water is critical to ensuring water reliabiity for our customers. Since the late 1970s we’ve been building a network of local wells to ensure reliability and reasonable costs. After all, local water costs less than water that must travel hundreds of miles through aqueducts to reach Southern California. IRWD's drinking water comes from two primary sources: local groundwater and imported water. The blending of these sources varies according to the time of year and your geographic location within the District. IRWD manages its supply and demand with careful research and analysis regarding flow, diversions, climate, customer demand and population estimates to ensure there will be an adequate supply of clean, reliable water well into the future.

In addition, IRWD has a robust recycled water program. Every gallon of recycled water used for irrigation or other non-potable purposes saves a gallon of drinking water. The District's diversified supply ensures a reliable water supply during times of drought, regulatory constraints and other emergencies. Additionally, our diverse water supply portfolio helps to keep rates as low as possible.

Groundwater

About 52% of our overall supply comes from local groundwater wells in the Orange County Groundwater Basin, and the Irvine and Lake Forest sub-basins. For many years, IRWD received almost all of our water from imported sources. To alleviate this dependency on costly imported water, IRWD began to develop a series of local wells in 1979. The Dyer Road Wellfield Project extracts low-cost, high-quality water from deep within the Orange County Groundwater Basin. IRWD now operates 27 groundwater wells. Click to learn more about IRWD's Groundwater.

Imported Water

IRWD buys 18% of its water through the Municipal Water District of Orange County, which buys water from the Metropolitan Water District of Southern California (MWD), a regional water wholesaler that delivers imported water from Northern California and the Colorado River.

State Water Project

The State Water Project, also known as the California Aqueduct, transports water 600 miles from Northern California to the southern portion of the state. It is owned and operated by the State of California and is the longest aqueduct system in the world, featuring 23 dams and reservoirs, 22 pumping plants that lift water to heights of 3,500 feet, and six power plants. The aqueduct is composed of 473 miles of canals, 175 miles of pipeline and 20 miles of tunnels.

Colorado River Project

The Colorado River Aqueduct brings water 242 miles from the Colorado River through deserts and over mountain ranges to its terminal reservoir, Lake Mathews, in Riverside County. The aqueduct system includes five pumping plants that lift the water 1,617 feet.

Recycled Water

IRWD produces about a quarter of our supply by capturing water that normally would run out to sea, treating it, and reusing it for irrigation and other non-potable, or non-drinking, uses. We also supplement our supplies by cleaning non-potable groundwater to make it suitable for irrigation. Every gallon of recycled water and cleaned groundwater we use saves a gallon of drinking water. Click to learn more about IRWD's Recycled Water Program.

Water Banking

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Strand Ranch Water Banking Project

Located in Kern County, the Strand Ranch Water Banking Project improves IRWD's water supply reliability by capturing low cost water available during wet years for use during periods of drought or critical need. Using a system of 502 acres of constructed groundwater recharge ponds on Strand Ranch, IRWD can store up to 50,000 acre-feet in the Water Bank and may recharge or recover up to 17,500 acre-feet in any single year. Click for more information about Water Banking.

Kern Fan Groundwater Storage Project

IRWD is partnering with Rosedale-Rio Bravo Water Storage District in the development of the Kern Fan Groundwater Storage Project, which will provide substantial water supply reliability benefits to the agencies. IRWD and Rosedale are actively pursuing both State and Federal funding for the project. Following are links to important documents related to securing State of California Water Storage Investment Program funding and Federal Water Infrastructure Improvements for the Nation (WIIN) Act Funding.

Water Storage Investment Program

On July 24, 2018, the California Water Commission voted to conditionally award the Kern Fan Project $67.5 million. IRWD and Rosedale are now working to complete additional requirements outlined in the program regulations in order to execute a final funding agreement and receive funds.

View the WSIP application
View the IRWD presentation overview of the project and WSIP application
View the Kern Fan Groundwater Storage Project Factsheet
View the WSIP Appeal Letter

Federal WIIN Act

On October 21, 2019, IRWD and Rosedale submitted a draft feasibility report to the United States Bureau of Reclamation (Reclamation) for review.

View the Draft Feasibility Report and

After reviewing the project proposal documents, Reclamation sent a letter on February 24, 2020, to IRWD and Rosedale requesting additional information.

In response to the Bureau’s request for additional information, IRWD and Rosedale submitted an updated feasibility report and appendices along with an additional information package on April 13, 2020. The additional information package includes responses to Reclamation’s comments along with supporting attachments.

View the Updated Draft Feasibility Report and

View the Additional Information Package and

In June, IRWD and Rosedale participated in a Design, Estimating and Construction (DEC) Review of the Project with Reclamation. The DEC Review included a virtual tour of the Project and an in-depth evaluation of risks and costs associated with the Project. On June 12, 2020, IRWD and Rosedale participated in a briefing on the findings of Reclamation’s DEC Review of the Kern Fan Project. In response to Reclamation’s findings, IRWD and Rosedale submitted the following Addendums and Exhibits to Reclamation on July 1, 2020.

Kern Fan Groundwater Storage Project Presentations:

View the Response to DEC Review Findings

In July, Reclamation released its final Design, Estimating, and Construction Review Report of the Kern Fan Groundwater Storage Project. The DEC Review Report and supplemental information submitted by IRWD and Rosedale serve as the basis for the Joint Resolution Memorandum, which concludes the DEC Review process.

View the Final DEC Review Report and
Joint Resolution Memorandum
- Joint Resolution Memorandum Attachment

Kern Fan Groundwater Storage Project Presentations:

Presentation to Lower Colorado Basin Regional Basin Regional Director Dr. Terry Fulp June 26, 2020
Presentation to Bureau of Reclamation Commissioner Brenda Burman August 5, 2020
Presentation to California-Great Basin Regional Director Ernest Conant August 19, 2020
Presentation to Bureau of Reclamation Policy Team August 20, 2020.

Water Supply Reliability Program

IRWD has purchased property in Riverside County that is located within the Palo Verde Irrigation District. Ownership of this land will eventually become another element of IRWD’s long-term program to increase water supply reliability for its customers during droughts and other potential water supply interruptions. This land is currently farmed by a tenant farmer; IRWD expects to continue with the practice. For more information please click here.

California H2O: Flowing for the Future

The Association of California Water Agencies created the "California H2O: Flowing For the Future" video series, which offer a statewide perspective on important water issues and feature interviews with member agencies to highlight the innovation and collaboration of local agencies.

"Urban Innovation" showcases state-of-the-art technologies and innovation being used to increase water supply and drought resilience.
"From Peaks to the Pacific" reinforces the need for headwaters management to protect the state's water supply reliability and water quality in the face of devastating wildfires.
"A Powerful Connection" examines water agencies' long history of renewable energy projects and energy efficiency practices.
"A Safe Supply" looks at local efforts to forge collaborations and use state-of-the-art water treatment technology to ensure delivered water is safe to drink.
"Tractors and Tech" showcases the increasingly sophisticated measures used to improve the efficiency of agricultural irrigation.
"Investing in Our Future" looks at the need to invest in aging infrastructure and highlights innovative ways in which water agencies are using technology to keep that investment cost as low as possible for customers.
"Fixing the Bay-Delta, What's at Stake" examines the key issues that make the Delta one of the state's most crucial water resources.
"Small Changes, Big Impact" highlights how water agencies have helped Californians embrace a more water-efficient way of life through education and rebate programs.