Metropolitan Water District of Southern California
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Integrated Water Resources Plan (IRP)

Approved by the board on October 12, 2010, the updated IRP is Metropolitan's strategic plan for water reliability through the year 2035, collaboratively developed with input from water districts, local governments, stakeholder groups and the public.

IRP Reports:
Executive Summary
(27.0 Mb. pdf)*
Full IRP Report (45.8 Mb. pdf)*
Technical Appendix (14.1 Mb. pdf)*

   Board Updates Integrated Water Resources Plan

Long-Term Conservation Program

Your WaterMetropolitan Adopts Long-Term Conservation Plan

At its August 2011 meeting, the board adopted the plan to help achieve the water use efficiency target in the 2010 Integrated Water Resources Plan Update (IRP Update). 
Board Letter with Attachment

Examples of Local Projects and New Technologies

Well heads like the North Las Posas well head in Calleguas MWD are used to inject water into the ground for future storage in the conjunctive use program.

Advanced membrane technology like these reverse osmosis filters are used to treat wastewater for beneficial use, resulting in near-distilled quality water at the Orange County Water Districtís Groundwater Replenishment System.

Rio Honda
Spreading Basins like the Rio Hondo desilting pond in Central Basin MWD are used to replenish our groundwater basins.

Click here for more examples


Metropolitan’s long-term water plan offers an innovative strategy to protect the region from future supply shortages, with an emphasis on water-use efficiency through conservation and local supply development. 

The board of directors of the Metropolitan Water District of Southern California, on October 12, 2010 updated the district’s Integrated Water Resources Plan, providing a roadmap for maintaining regional water supply reliability over the next 25 years.

“Change is the one thing that’s certain about future water resources for Southern California. Whether it is changes in climate patterns, or changes in environmental regulations that could dramatically affect water availability, adaptation will be critical to maintaining a dependable, high-quality supply,” said Metropolitan board Chairman Timothy F. Brick.

“With this updated plan, we stand prepared to meet these unprecedented challenges,” he said. “It also sets a benchmark to measure progress in the future and to signal when changing circumstances should trigger adaptive actions.”

The framework places an increased emphasis on regional collaboration. Earlier plans dating back to 1996 set a regional reliability goal of meeting full-service demands at the retail level under all foreseeable hydrologic conditions. This updated plan seeks to stabilize Metropolitan’s traditional imported water supplies and to continue developing additional local resources.

It also advances long-term planning for potential future contingency resources, such as storm water capture and large-scale seawater desalination, in close coordination with Metropolitan’s 26 member public agencies and other utilities.

The updated IRP strikes a balance through a three-component approach:

• A core resources strategy represents baseline efforts to manage water supply and demand conditions and to stabilize Metropolitan’s traditional imports from the Colorado River and Northern California through the Sacramento-San Joaquin Delta. This strategy is based on known factors, including detailed planning assumptions about future demographic scenarios, water supply yields, and a range of observed historical weather patterns. Under this strategy, Metropolitan and its member agencies will advance wateruse efficiency through conservation and recycling, and with further local development such as groundwater recovery and seawater desalination.

• A cost-effective “supply buffer” will enable the region to adapt to future circumstances and foreseeable challenges. The buffer seeks to help protect the region from possible shortages caused by conditions that exceed the core resources strategy, starting with increased conservation and water-use efficiency on a region-wide basis.

• Foundational actions guide the region in determining alternative supply options for long-range planning. If future changed conditions—such as climate change or the availability of resources—exceed what is covered by Metropolitan’s core resources and supply buffer, these alternatives would provide a greater contribution to water reliability than Metropolitan’s imported water sources or any other single supply. These actions - including feasibility studies, research and regulatory review - would provide the foundation to develop alternative resources, if needed.

Metropolitan General Manager Jeffrey Kightlinger said the updated plan builds on the success of existing conservation programs and recycled water projects, such as plumbing code revisions and direct incentives.

“The focus will be on California’s new requirement to lower residential per-capita water use 20 percent by the year 2020. The ‘20 x 2020’ plan gives local communities flexibility to meet this target while accounting for previous conservation and recycling efforts,” Kightlinger said.

IRP Reports:
Executive Summary
(27.0 Mb. pdf)*
Full IRP Report (45.8 Mb. pdf)*
Technical Appendix (14.1 Mb. pdf)*

If you have questions please E-mail IRP.

* All PDF documents on this site require Adobe Acrobat Reader 4.0 or higher. If you do not have Adobe Acrobat Reader, or must upgrade your version, you may download it for free from Adobe's website. If you are using a dial-up modem, please note that many of these documents are large in size and take a long time to open. Use of software other than Adobe Reader may cause discrepancies from the original documents. These risks will be assumed by the reader.

Page updated: November 29, 2011