Strategic Investments Create A Vibrant Regional Future

A safe and reliable water supply is crucial to sustain the San Diego region’s $240 billion economy and quality of life for 3.3 million residents. To maximize the reliability of the region’s most precious resource, the Water Authority is executing a successful long-term strategy to diversify its water resources, make major upgrades in the regional water delivery and storage system, and improve water-use efficiency.

While the San Diego region has sunshine in spades, it doesn’t have significant local water supplies. In fact, human history in this semi-arid region has always been marked by the search for reliable water supplies. With intermittent rainfall and sparse groundwater, the region today relies on low-cost base water supplies from the Colorado River Quantification Settlement Agreement, other imported water supplies, and a variety of local sources, including water recycling.

After decades of strategic investments, the Water Authority today is a model for statewide efforts to develop diversified water supply portfolios. The San Diego region’s resources range from the nation’s largest seawater desalination plant to the nation’s largest ag-to-urban water conservation-and-transfer agreement. These assets provide supply security for the region’s diverse economy that includes tourism, agriculture, biotech, defense and other sectors.

Water Resource Portfolio

Decreasing our dependency on non-renewable water sources, increasing the diversification of our water supply and bettering the efficiency and conservation of how we use and procure our water.

1991
1991 Water Supply Source
2021
2045*
2045 Water Supply Source
  1. *Based on the 2020 Urban Water Management Plan.

  • Conserved Water/ IID
  • Conserved Water/ Canal Lining
  • Metropolitan Water District
  • Seawater Desalination
  • Local Surface Water
  • Recycled Water
  • Groundwater
  • San Luis Rey Water Transfer
  • Potable Reuse

Increasing Local Supplies

The Water Authority also collaborates with its 24 local member retail agencies to develop local supplies such as groundwater and recycled water. The next big local supply will come from water purification projects that are under development across the region.

In 2020, about two-thirds of the region’s water supplies are from the Colorado River, about 20 percent is from local sources and the rest is from the Northern California. Regardless of the source, all the water delivered to homes and businesses across the region meets strict state and federal quality standards.

Want to dig deeper and learn more?
download this documentWater Supply Fact Sheet

Water Supply Management

Enhancing Facilities & Efficiency

Another important part of the Water Authority’s long-term strategy involves major upgrades to key facilities. This includes the construction of Olivenhain Dam in the early 2000s and raising San Vicente Dam a decade later as part of the agency’s Emergency & Carryover Storage Project. In 2017, the E&CSP was honored by the American Society of Civil Engineers as the top engineering project in the world — “an investment that ensures the public’s health, safety, and welfare in case of disaster.”

At the same time, the Water Authority has played an important role locally and statewide to increase water-use efficiency. Working with its member agencies and other partners, the Water Authority offers programs and resources that improve water-use efficiency for residential, commercial, and agricultural users. Thanks to widespread adoption by the community, WaterSmart choices are a way of life in the San Diego region.