MWD Water Supply Roadmap Emphasizes Regional Collaboration
The board of directors of the Metropolitan Water District of Southern California on Oct. 12 updated the district’s Integrated Resources Plan (IRP), 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.
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 stormwater 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 water-use 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.
The Metropolitan Water District of Southern California is a cooperative of 26 cities and water agencies serving 19 million people in six counties.