Recycled Water

Recycled Water

Innovative Approach. Reliable Source.

Water is too valuable to use just once. So at IRWD, we meet about 25% of our service area's water demands with recycled water. IRWD's recycled water is not for drinking or for other uses inside your home. But it is a key component of IRWD's conservation and water use efficiency program – because every gallon of recycled water saves a gallon of drinking water for potable uses. Recycled water extends our drinking water supplies, reduces the need for additional drinking water facilities, reduces the amount of treated sewage discharged into the ocean, reduces our reliance on costly imported water, and increases our water supply reliability.

Our Recycled Water Program
IRWD is a national leader. Our long history of recycled water achievements began in 1963 when our forward-thinking Board of Directors implemented its vision to integrate water recycling into the overall design of our community. As a result, IRWD's scope of services was expanded to include sewage collection and treatment services for producing recycled water. The district began delivering recycled water to its agricultural customers within four years of its initial commitment. Today, IRWD's nationally recognized recycled water program encompasses a wide variety of uses, such as landscape irrigation, industrial processes, and toilet flushing in commercial buildings.


Recycled water production uses natural biological treatment to duplicate nature's own cleaning processes. Sewage from the community is collected and treated to tertiary standards at the Michelson Water Recycling Plant in Irvine and at the Los Alisos Water Recycling Plant in Lake Forest. Tertiary treatment is a high level of treatment that results in excellent-quality recycled water that can be reused in the community for state-approved nondrinking water purposes such as watering lawns and flushing toilets.

It takes about 16 to 18 hours to produce recycled water – from the time the sewage enters the plant until the finished product is disinfected and ready for distribution. Once treated, recycled water is delivered throughout the IRWD service area through our extensive recycled water distribution system. Our dual distribution system, which keeps recycled water completely separate from drinking water, uses purple pipe infrastructure to easily identify recycled water systems. IRWD pioneered the purple piping, which has become the international symbol for recycled water. All recycled water produced at IRWD facilities meets or exceeds state and federal mandates. Currently, we deliver more than 25 million gallons of recycled water per day to more than 4,000 customers.

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The Distribution System
The cornerstone of IRWD's extensive recycled water program is the development of a dual distribution system – one set of pipes for drinking water and another set for recycled water. IRWD's recycled water distribution system reaches most of our service area and continues to grow with the community. Beneath many streets lie three pipelines: one for drinking water delivery, one for sewage collection, and a third – purple pipe – for distribution of recycled water.
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The Results
IRWD's recycled water consistently meets or exceeds the California Department of Public Health's stringent water quality criteria for water reuse. As a result, IRWD has been a leader in all aspects of recycled water, including research and design as well as policies and regulation. The high-quality, polished recycled water that leaves the Michelson Water Recycling Plant in Irvine can be used for almost every purpose except drinking.
The Uses
Recycled water is used primarily for landscape and agricultural irrigation. Landscape irrigation uses include parks, school grounds, golf courses, freeway landscaping and watering of common areas managed by many homeowners associations. In addition, recycled water is used for front and backyard irrigation in eligible residential lots, for industrial processes, for toilet flushing in some office buildings, and in cooling towers.

Portola High School and IRWD Recycled Water

On May 19, 2016, the California Department of Toxic Substances Control (DTSC) issued a report to Irvine Unified School District regarding a soil assessment of the Portola High School site.

Page 32 of the final report contains the statement that: "low concentrations of some of the VOCs detected in the soil gas samples including chloroform and dibromochloromethane may be a result of the chlorination of the recycled water."

Chloroform and dibromochloromethane are common, regulated constituents that can be produced during the water disinfection process, and trace levels could be present in IRWD's recycled water. These low levels are well within the stringent limitations established by the California State Water Resources Control Board for safe water reuse under Title 22 of the California Code of Regulation.

IRWD recycled water is rigorously monitored and consistently remains within these standards. IRWD recycled water is safe for all permitted uses and applications.


Recycled Water Policy Paper

IRWD is a leader in recycled water development and use. The District currently meets almost a quarter of our total water demands with recycled water through irrigation, agriculture, toilet flushing, cooling towers, and industrial processes. Recycled water is a key component of IRWD's conservation and water use efficiency programs because every gallon of recycled water used results in a gallon of drinking water that can be saved for potable uses increasing local supply reliability and resulting in less importation from the Delta or the Colorado River. Despite the enormous success IRWD has achieved with recycled water, there is still more we hope to do with our recycled water resources.

IRWD supports the expanded use of recycled water because it is an important component of California's sustainable water future and economic strength. However, the current regulatory and permitting framework for recycled water, established more than 20 years ago, is an obstacle to developing cost-effective recycling projects. IRWD advocates for state and federal policies which reflect the current scientific understanding of the benefits of recycled water and the appropriate limits to its use.

For more information on the Recycled Water Use Economic Incentives policy principles adopted by the IRWD Board of Directors

Indoor Recycled Water Use
AB 1406 (Huffman), successfully sponsored by IRWD in 2007, changed the California Water Code to allow recycled water to be used for indoor uses such as toilet flushing and cooling towers in multi-level condominium complexes.
California Plumbing Code
SB 283 (DeSaulnier), successfully sponsored by IRWD in 2009, paved the way for the adoption of California Plumbing Code provisions setting forth design standards for the safe plumbing of approved buildings with both potable and recycled water systems allowing.
Water Softeners
AB 1366 (Feuer/Caballero/A. Strickland) was successfully sponsored by a coalition of water agencies including IRWD in 2009. The bill provided water agencies in specified areas of the state with a critical tool for managing controllable salts discharged by self-regenerating water softeners.
Water Recycling Act
 In partnership with the California WateReuse Association, San Diego County Water Authority, Eastern Municipal Water District, West Basin Municipal Water District, and El Dorado Irrigation District, IRWD co-sponsored AB 2398 (Hueso), which would have enact the Water Recycling Act of 2012. In 2013, IRWD actively supported AB 803 (Gomez) sponsored by the California WateReuse Association. These bills sought to expand the use of recycled water in California by improving and streamlining the existing regulatory and permitting process for recycled water projects to reflect current scientific study and advances in treatment technology.
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Recycled Water Customer, Agency and Technical Information

Mark Tettemer
Manager of Recycled Water
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General Inquiries, Students, and Media Contact Information

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