Water Use

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Improved more than 1 percent from
2015 to 2016

How are we doing?

Water use received a thumbs-up because estimated per capita residential daily water use in the San Diego region decreased from 96 gallons in 2015 to 82 gallons in 2016. This means San Diegans reduced use by nearly 15% from 2015 to 2016. In 2016, California was under an emergency drought declaration, which mandated water use restrictions for local water agencies. In San Diego county, all water districts decreased their estimated average municipal and industrial water use from 2015 to 2016. Additionally, state regulations required urban water suppliers to report monthly residential water use data. The increased availability of data has made it easier to track and benchmark water use by districts. See more information.

In 2016, San Diego received the most rain since 2011, and recorded the lowest residential water use per capita in at least 17 years.

Data Sources: National Oceanic and Atmospheric Administration, California Nevada River Forecast Center, Monthly Precipitation Summary, 2016; San Diego County Water Authority, Annual Report, 2017

Why is it important?

  • Transportation and treatment of water, treatment and disposal of wastewater and the energy used to heat and consume water account for nearly 20% of the total electricity used in California and 30% of nonpower plant-related natural gas consumption.
  • Annually, more than half of the water county residents use, and half of all urban water use in California, is for outdoor irrigation.

Among urban water suppliers in San Diego, residents in the Santa Fe Irrigation District have used the most water per person in every quarter since urban water suppliers started reporting this data to the state in Q3 of 2014. Overall, the trend appears to be declining water use in all districts.

Data Source: State Water Resources Control Board, Urban Water Supplier Report, 2017

In 2016, the county average for municipal and industrial daily water use per capita was 109 gallons, which is 22 gallons less per day than in 2015. Municipal and industrial water use includes potable water consumption for residential, business and institutional uses, deducting Transitional Special Agricultural Water Rate program use.

Data Source: San Diego County Water Authority, 2017

Change in Estimated Municipal & Industrial Daily Potable Water Use per Capita

(FY 2015 - FY 2016)

From 2015 to 2016, the water districts of Poway, Pendleton, Ramona, Santa Fe and Yuima had the greatest decrease in municipal and industrial daily water use per capita with more than a 20% reduction. Vallecitos Water District had the smallest decrease.

Data Source: San Diego County Water Authority, 2017

  Idea for Change

Policymakers should continue to advance potable reuse and recycled water programs in San Diego County. For example, the San Diego City Council has approved an accelerated building schedule for Pure Water San Diego, a wastewater recycling program designed to increase water independence by providing one-third of the city of San Diego’s supply by 2035. This means phase one of the project will begin recycling sewage into 30 million gallons of drinking water a day by 2021, six years sooner than previously scheduled. Currently, the city relies on importing approximately 85% of its water supply predominantly from the Colorado River and Northern California Bay Delta at a cost that has tripled over the past 15 years. Learn more.

  Bright Spot

The San Diego County Water Authority stored 100,000 acre-feet of “carryover” water behind the San Vicente Dam between 2015 and 2016, years ahead of projections. The San Vicente Dam was raised 117 feet in 2014 to help store additional water for regional use during times of water scarcity. This facility proved beneficial when state-mandated drought response conservation efforts kicked into high gear in 2015, enabling the Water Authority to store conserved water. The locally stored water helped the San Diego region pass the state’s supply reliability “stress test,” which demonstrated the county has at least a three-year water supply to meet dry year demands. Learn more.

  What are we measuring?

We measure water use by calculating residential water consumption per person using total residential water use in San Diego County and the estimated population served by the San Diego County Water Authority. We also measure the daily municipal and industrial water use per person by water agency which includes potable water consumption for residential, business and institutional uses, deducting Transitional Special Agricultural Water Rate program use. In addition, we use the State Water Resources Control Board data to track quarterly residential water use by water agency. Learn more about the data.