Water Use

How Are We Doing?

Water use received a thumbs up because daily residential water consumption in San Diego County decreased by 8.8% from 91 gallons per capita in 2018 to 83 gallons in 2019. Residential water use still remains below the 2011 pre-drought levels, which at its peak in 2007 reached 119 gallons per capita. The 2018 year was an extremely dry year but the 2019 year saw rainfall return to the level experienced in 2017, which likely contributed to water use returning to its 2017 level. All but three of the county's 24 water districts increased their estimated municipal and industrial water use from 2018 to 2019Want to know more about what we're measuring?

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Improved more than 1 percent from 2018 to 2019

Residential water use per capita in 2019 decreased as compared to 2018, and remained lower than historical rates.

San Diego County's water supply has diversified significantly over the last couple of decades. While the San Diego County Water Authority has decreased the region's reliance on water from the Metropolitan Water District which serves parts of Los Angeles, Orange, San Diego, Riverside, San Bernardino and Ventura counties, the region still remains heavily reliant on water from the Colorado River (through water supply purchases from the Metropolitan Water District of Southern California and through water conserved and purchased through the Imperial Irrigation District and through water conserved by lining the All-American and Coachella canals).

In 2019, National City had the lowest municipal and industrial (M&I) water use at 76 gallons per capita daily. Yuima's high per capita M&I potable water use occurs because a large amount of water used for horticultural irrigation is classified as M&I, and the district services a small population (less than 2,000 people).

*This data includes agricultural water use served by local water agencies.

Fresh water is stored in 24 reservoirs across the county. The San Diego region has a mediterrean climate, and experiences the largest variability in annual rainfall of any other region in the continental United States. Rainfall and runoff supply varies annually and only some of this supply reaches our reservoirs by transport from seven major stream and watershed systems in the region. These 24 reservoirs have a combined capacity of about 740,000 acre-feet

Click through to explore each of our region’s reservoirs and their contributions to water supply. Toggle to the menu bar in the top left corner to explore other features of this map. 

Why is Water Use Important?

High quality of life means the region boasts a thriving economy and a healthy environment accessible to all in the community.

  • Environment: The San Diego region has many examples of moving towards integrated regional water management strategies, which is a collaborative effort aimed at developing long-term water supply reliability, improving water quality, and protecting natural resources. The San Diego County Water Authority, along with the City of San Diego and the County of San Diego, has developed an Integrated Regional Water Management Plan (IRWMP), and the IRWMP builds on local water and regional management plans within the San Diego Region. The IRWMP was developed with input from a diverse group of stakeholders that make up the Regional Advisory Committee, representation includes water management agencies, resource conservation agencies, tribes and nonprofits. The IRWMP was updated in 2019 and includes information on climate change science as well as a stormwater capture feasibility study. 

    Local organizations like San Diego Coastkeeper are developing new frameworks and partnerships for enhancing regional water supply through the lens of increased climate resilience. Their integrated management approach, “One Water,” prioritizes multi-benefit solutions, community health, and environmental resilience. This approach incorporates a suite of green infrastructure projects, innovative stormwater capture, wastewater recycling programs, and habitat restoration practices that provide benefits such as pollution reduction, increased water supply, and improved community and ecosystem health. As part of this work, San Diego Coastkeeper put together an educational video on the benefits of, “Integrated Water Management as a Pathway for Climate Resilience.”

  • Economy: Clean water is crucial to human and environmental health, but it’s also a large driver of a healthy economy. In 2018, “Every $1 invested in water infrastructure results in a $1.80 increase in the region’s gross regional product." Maintaining strong, safe water transportation infrastructure is key to maintaining long term regional resilience. Over the past two decades, diversification efforts have helped the San Diego region significantly reduce its reliance on the Metropolitan Water District from 95% in 1991 to 40% in 2018, and a projected 11% in 2020 and 2% by 2035.  

    Research has shown that a reliable water supply and the infrastructure necessary to store, move, treat, and deliver are essential to the development of an advanced economy. These factors are indispensable for supporting the diversity of industries within the regional economy. Interruptions of the region’s water supply would have severe impacts on all local industries.

  • Equity: California’s climate has historically been marked by long droughts and severe floods, with stark regional differences in water availability and demand. As our climate changes, water challenges throughout California have increased over time. One of these challenges is ensuring that all individuals have access to, and awareness of, measures to improve water quality. The San Diego Regional Climate Collaborative (Climate Collaborative) through a project funded by The San Diego Foundation has been working to advance the nexus of water and equity in the San Diego region. Through this project, the Climate Collaborative developed content to amplify case studies that highlight projects and best practices advancing equity driven projects around water use, stormwater and water quality. As part of this work, the Climate Collaborative developed an interactive ESRI Storymap that further analyzes the nexus of water and equity and highlights projects focused on making improvements in underserved communities.

Want to learn more? Watch the Voice of San Diego's San Diego 101 video on how the region is working to keep up with the demand for water and buy its way out of potential water shortages. San Diego 101 is a series from Voice of San Diego made to educate San Diegans about some of the most important issues that shape our region.

Regional Response


In July 2019 Gov. Gavin Newsom of California signed into law Senate Bill 200, a measure to provide $130 million annually for the next decade to rebuild water infrastructure in many of the poorest communities across the state. This created the “Safe and Affordable Drinking Water Program” to support projects to clean up contaminated drinking water and help cash-strapped rural water districts. This program has a strong emphasis on enhancing the safety of drinking water for many communities of concern who have long lacked access to this vital resource. 

In 2019, the California State Water Resource Control Board passed the Recycled Water Policy and began focusing efforts on recycled water facilities. Recycled water is “water which, as a result of treatment of waste, is suitable for a direct beneficial use or a controlled use that would not otherwise occur and is therefore considered a valuable resource”. This policy supports use of recycled water to diversify community water supplies and mitigate the impacts of climate change on California's water resources.


Pure Water San Diego is the City of San Diego's phased, multi-year program that will provide one-third of San Diego's water supply locally by the end of 2035. The Pure Water San Diego Program will use proven water purification technology to clean recycled water to produce safe, high-quality drinking water. The Program offers a cost-effective investment for San Diego's water needs and will provide a reliable, sustainable water supply. In December 2019, the Metropolitan Water District of Southern California voted to spend $285.6 million in support of the City of San Diego’s Pure Water Project.

Pure Water Oceanside will purify recycled water to create a new, local source of high-quality drinking water that is clean, safe, drought-proof and environmentally sound. The program will produce enough water to provide more than 30% of Oceanside's water supply. A high reliance on imported water leaves the city vulnerable to the threat of climate change and recurring drought. Also, diverting water from these imported sources, such as the Colorado River, negatively affects its ecosystems which fish and wildlife depend on. Pure Water Oceanside and other local programs diversify our water supply and reduce reliance on imported water and create a local and sustainable water source for Oceanside.


The City of San Diego and local nonprofit, Groundwork San Diego, collaborated to improve climate resiliency in the primarily disadvantaged community of Southcrest in south San Diego. The project worked to increase the area's water quality and habitat by removing invasive plants from adjacent public and private properties in the Chollas Creek channel. The Chollas Creek watershed is located in an urbanized area of south San Diego composed primarily of communities characterized as disadvantaged by the California Department of Water Resources, and with the potential to be disproportionately impacted by climate change. In order to implement a holistic approach to removing non-native plants from the Chollas Creek channel in Southcrest, the City of San Diego coordinated with Groundwork San Diego to schedule work on adjacent public and private parcels at the same time. Working together yielded efficiencies and an opportunity to educate the public about the importance of the creek and its maintenance.


What Are We Measuring?

We measure year-over-year residential, and municipal and industrial water use per person in San Diego County by water agency. In addition, we compare per capita estimated residential water use to the year’s rainfall at the San Diego International Airport. Learn more about the data.