How We Plan

Etiwanda Pipeline

Southern California’s
Water Planner 

With a nearly 100-year legacy of water resource planning for Southern California, Metropolitan is tasked with looking ahead to foresee the needs of the region, and the supply challenges we might encounter. Planning is a cornerstone of Metropolitan's reliability and we seek out innovative solutions and strategic investments to fulfill our mission of delivering reliable, high-quality water now and into the future.

Ensuring water reliability for 19 million Californians is no small task. Half of Southern California's water is imported from hundreds of miles away. And those sources are increasingly under threat from climate change, longer periods of drought and earthquakes. Metropolitan must remain reliable in the face of these challenges. Planning remains key.

Metropolitan's Climate Adaptation Master Plan for Water will consider climate scenarios alongside plans for water resource development and management, emergency preparedness and response, and financial sustainability to prepare the region for the potential impacts.


Adapting to Weather Extremes

California’s recent climate extremes highlight the challenges ahead in managing our water supplies. From historic droughts to record-setting levels of rain and snow in the span of just a few years, the imported water sources our region traditionally has depended on - from the Colorado River Basin and from Northern California - are becoming more stressed and less sustainable in the midst of a changing climate.

Metropolitan has long recognized the importance of securing and managing our state's precious water resources against future uncertainties through our Integrated Water Resources Plan. We initiated this blueprint for planning in the mid-1990s and have since refined the IRP several times. With each major update, we have revised and adapted our management objectives and approaches to meet the projected water needs of Southern California.

The next major update to Metropolitan's long-term planning process is being developed through the Climate Adaptation Master Plan for Water. This updated long-term planning process will integrate complex climate modeling, various water supply and demand scenarios mapped over a 25-year horizon and cost-conscious business forecasting to ensure that we are well-positioned to make strategic and sustainable investments that will benefit all of Southern California.

Our CAMP4W process includes collaboration and engagement with our member agencies and elected leaders, community-based organizations, local businesses and the public. We are seeking feedback and dialogue as we chart our sustainable path forward and work together to build a stronger, more resilient water future for Southern California.

Learn More 

California Aqueduct

Urban Water Management Plan

Metropolitan demonstrates its ability to meet expected water demands in the region for the next quarter century, even under drought conditions, through its Urban Water Management Plan. Required by the state, the plan provides a summary of Metropolitan’s anticipated water demands and supplies through 2045, and shows we will meet demands under normal water years, single dry-years, and five-year drought sequences. At the center of Metropolitan’s 2020 UWMP plan is its diverse portfolio of water resources, including imported supplies from the Colorado River and State Water Project; local projects offering water recycling and groundwater recovery; short- and long-term water transfers; storage, both inside and outside of the region; and continued investment in water-use efficiency and demand management.

The plan describes implementation strategies and schedules and other relevant information and programs. The UWMP, prepared as part of the 2020 Integrated Water Resources Plan planning process, is updated every five years in compliance with the California Water Code. The Water Shortage Contingency Plan includes Metropolitan's efficient management and planned actions to respond to actual water shortage conditions. It improves preparedness for droughts and other impacts on water supplies under varying degrees of water shortages.  The WSCP complies with the California Water Code and is updated as needed. 


2020 UWMP

Water Shortage Contingency Plan

2020 Reference Materials

2015 Reference Materials

Highlights of the 2020 UWMP and WSCP


  • Metropolitan has water supply capabilities sufficient to meet expected demands under normal water year hydrologic conditions, a single dry year condition and a period of drought lasting five consecutive water years.

  • The reliability assessment recognizes the long-term impact of investments in demand management along with a diversified resource portfolio with programs for the Colorado River Aqueduct, State  Water  Project, Central Valley storage and transfers, local resources, and in-region storage. 

  • Metropolitan has comprehensive plans to address frequent and severe periods of droughts, with progressive actions for shortage conditions including greater than 50 percent shortage and a catastrophic interruption in water supplies.

  • Metropolitan regards water quality with paramount importance to water supply reliability, ensuring that delivered water meets or surpasses all state and federal drinking water standards. 

  • Metropolitan faces a number of challenges in providing adequate, reliable, and high-quality supplemental water supplies for Southern California, including dramatic swings in annual hydrologic conditions, long-term hydrologic changes due to climate change, operational constraints on the State Water Project, and water quality challenges such as algae toxins, PFAS, and the identification of constituents of emerging concern.  These challenges are addressed through a variety of actions for supply development, demand management, and water quality protection.
DVL Refilling

Water Surplus & Drought Management Plan

Our Water Surplus and Drought Management Plan provides a framework for managing Metropolitan’s resources in periods of surplus and shortage to help achieve 100 percent water reliability for Southern California. To reach this goal, the plan’s guiding principle is to store and manage water available during wet periods and work collaboratively with member agencies to minimize the impacts of water shortages in dry years. At the start of the year, Metropolitan develops an initial plan for both wet and dry hydrologic conditions, and then regularly Metropolitan evaluates available water supplies and existing water storage levels to determine the appropriate management actions identified in the plan.

The WSDM Plan has served Metropolitan and Southern California well over the years, through both dry and wet periods. Thanks to this comprehensive water management strategy and actions we’ve taken to strengthen our reliability, Metropolitan ended 2020 with a record amount of water in storage.

How We Plan

Long-Term Conservation Plan

Metropolitan and its member agencies have long been leaders in water conservation, a fundamental component to Southern California’s water reliability. In 2009, at the urging of Metropolitan and its member agencies, the California Legislature mandated urban retail water providers to achieve a 20 percent per-capita reduction in water use by 2020. To support this goal, which also is outlined in Metropolitan’s 2010 IRP Update, our board adopted the Long-Term Conservation Plan, which identified the strategies and actions to reach that target.

Metropolitan exceeded this reduction five years ahead of schedule in 2015, thanks in part to an emergency statewide drought declaration urging residents and businesses to limit their water use. We’ve worked to help Southern Californians continue their water-saving ethic by creating lasting changes in consumer values, incentivizing the purchase of water-efficient devices, conducting outreach and education, and advocating for smarter building and plumbing codes.

Potable Per Capita Water Use graphic

Strengthening Resilience to Natural Disasters

Southern California’s geographic location puts us at risk for several types of natural disasters. Contingency planning and preparation are essential when faced with the possibility of having our water supply interrupted by earthquake, landslide, flood or other natural disaster.

Local Hazard Mitigation Plan

Metropolitan is working collaboratively with its 26 member agencies and county emergency managers throughout the region to develop a Local Hazard Mitigation Plan, which identifies and analyzes a comprehensive range of strategies and projects to reduce the impact of natural hazards to Southern California’s water supplies.

The LHMP is vital to help ensure Metropolitan can continue delivering on its mission to provide its service area reliable supplies even in the face of emergencies. Development of the LHMP began with data collection, analysis of existing conditions, and outreach.

For questions, email [email protected].

Learn more about Local Hazard Mitigation Plans

Prepared for the Big One


Metropolitan is prepared to ensure Southern California has water even in a worst-case scenario: a major earthquake. We have programs to improve the resilience of our infrastructure against earthquakes and we’re prepared to respond in case of emergency and restore our systems as quickly as possible.  We also have emergency reserves set aside in the event our imported supplies are cut off while repairs are being made. Our Seismic Resilience Strategy is a multi-faceted approach that involves coordination among several key areas within Metropolitan as well as close collaboration with the California Department of Water Resources and the Los Angeles Department of Water and Power, owners of the other two major imported water conveyance systems of the region, to enhance regional seismic resilience.

Metropolitan’s Dam Safety Program

Metropolitan owns and operates 20 reservoirs and 24 dams that store or manage water throughout Southern California.  Under the jurisdiction of the California Department of Water Resources Division of Safety of Dams the structures are regularly inspected by Metropolitan staff and the DSOD to ensure they continue to operate safely.  All our dams are classified for potential downstream impacts to life and property.  FEMA categorizes the downstream hazard potential into three categories of increasing severity:  Low, Significant, and High with the DSOD adding a fourth category of Extremely High.

The DSOD reports that all of Metropolitan’s dams are safe for continued operation.  Please email us for more information on Metropolitan’s Dam Safety Program.

Our Program

Our dam monitoring systems collect data from a portfolio of instrumentation to monitor their safety and performance. Parameters measured include dam internal pressures, water levels, seepage flows, and deformation. Staff regularly review instrumentation data for any signs of potential dam safety issues. Instrumentation data reports are submitted to the DSOD on an annual basis.

Our engineers perform dam inspections of all dams on a monthly or quarterly basis, and at least once a year in the presence of DSOD staff for dams that are High or Extremely High Hazard.

Inspection reports are submitted to the DSOD on an annual basis.

Periodic assessments are performed by staff and independent consultants to evaluate the performance of the dams and to identify any necessary improvements. Staff coordinates with the DSOD to ensure these assessments are completed in accordance with all dam safety regulations.

Inundation maps have been prepared by Metropolitan for all 24 dams, and all have been formally approved by the DSOD. Our inundation maps indicate the extent of flooding that could result from a hypothetical catastrophic failure of a dam to inform local emergency management authorities of all potentially affected areas. Additional information is available on the DSOD website.

One of the most important elements of Metropolitan’s dam safety program is planning and preparing for potential emergencies.  The planning process includes preparing the flood inundation maps, developing and maintaining an Emergency Action Plan for each dam in coordination with local emergency management authorities, regular maintenance and testing of dam monitoring systems, regular maintenance and exercising of all emergency dewatering equipment, and periodic reviews of EAPs at least annually.

Drought gardens