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Established in 1961, IRWD provides drinking water, waste water collection and treatment to produce recycled water. IRWD’s tertiary treatment of wastewater at its Michelson Water Recycling Plant (MWRP) results in an excellent quality of recycled water that is used for landscape and agricultural irrigation, and for industrial and commercial needs. IRWD’s proactive long-term planning identified the need to expand MWRP in order to meet the projected 56 percent increased recycled water demands by the year 2025.



In 1967 IRWD’s Michelson Water Recycling Plant began delivering approximately two million gallons per day recycled water to agricultural users. Over the years IRWD’s water recycling program grew from this limited use to a nationally-recognized program that provides recycled water for a variety of other non-drinking water uses.  Have your ever seen the lilac colored pipes? This indicates a recycled water source first implemented by the IRWD. This signature Lilac or Light purple pipes have since been adopted by other areas of the states and the western region.  The need for water continues to grow and the recycled water system must grow along with it.  By 2008, MWRP’s capacity had grown to 18 mgd.  Planners estimate that, when the service area reaches “final build out” in approximately 2025, a recycled water capacity of 33 million per day will be required to meet demands. A master plan was prepared to ensure that the plant will meet these requirements. A second plant expansion is nearly complete and will increase the MWRP by an additional 10 million gallons per day.


About 20 percent of IRWD’s current supply is recycled water, enough to provide landscape irrigation for 80 percent of the District’s business and community customers including parks, school grounds, and golf courses. Every gallon of recycled water used to irrigate crops or landscaping saves a gallon of drinking water, an equation that helps keep IRWD’s water rates among the lowest in Orange County. The MWRP Phase II Expansion will enable IRWD to provide water to meet the future needs of our growing community, while decreasing IRWD’s dependence on imported drinking water.

Project Partners

Assisting IRWD with the project construction is J. R. Filanc Construction Company (contractor), Bergelectric Corp. (electrical sub-contractor), Malcolm Pirnie (construction management), HDR/Tetra Tech/ VA Consulting (design), Borchard Surveying and Mapping (surveying), and Ninyo & Moore/ NMG Geotechnical, Inc. (geotechnical). SABP Reprographics (supplying all printed matter).

You too can help with your own efforts at recycling. Try putting a bucket in the shower and using the runoff water in your garden or to rinse off the patio. Only run the dishwasher when it is completely full or even better hand wash your dishes. Every little bit counts to help recycle our precious resource.