How San Diego secured its water supply, at a cost

As a worsening drought forces millions of Californians to face mandatory water restrictions, one corner of Southern California has largely shielded itself from supply issues: San Diego County .

For western water planners, the path he took to get there serves as either a blueprint or a cautionary tale.

Over the past three decades, San Diego County has diversified its water supply, stepped up conservation, and invested in expensive water infrastructure, including the Western Hemisphere’s largest desalination plant, which removes salt and impurities. seawater. As a result, the water agency that serves 24 water utilities, including the city of San Diego, says it can avoid cutoffs until at least 2045, even during dry periods. But this security comes at a cost.

San Diego County water is among the most expensive in the nation, costing about 26% more at the wholesale level in 2021 than that of the Metropolitan Water District, which serves Los Angeles and surrounding counties. Now two rural irrigation districts in San Diego County, home to major avocado industries, want to spin off from the regional water supplier, saying they can buy cheaper water elsewhere. If they succeed, San Diego County water could become even more expensive.

“The situation in San Diego is very surprising, very striking,” said Michael Hanemann, an environmental economist at Arizona State University who was recently commissioned to study water costs in the region for a California agency. “I think it’s a harbinger of something that’s going to happen elsewhere in California and elsewhere in the United States.”


San Diegans hasn’t always been quiet during the drought. In the 1990s, a severe drought reduced the region’s water supply by 30%. At the time, almost all of its water came from the Metropolitan Water District, the nation’s largest water supplier. That experience and a strained, dysfunctional relationship — say California water experts — with water officials in Los Angeles have spurred San Diego County’s decades-long aggressive pursuit of self-sufficiency. in water.

“At that point, our community came together and said, ‘We’re not going to find ourselves in this situation again. We have to plan for our own reliability,” said Sandy Kerl, chief executive of the San Diego County Water Authority.

So in 2003, the water authority entered into an agreement to obtain water from the largest user of the Colorado River, the Imperial Irrigation District in southern California. San Diego County funded repairs to leaky Imperial-owned canals and signed a historic water transfer agreement. Today, it receives about 55% of its total supply from Imperial under the deal.

The water authority has also helped farmers use less water. He raised dams to increase the storage capacity in the reservoirs. He offered discounts to homeowners who ripped up lawns for water-efficient alternatives.

In 2012, San Diego County reached an agreement to obtain 10% of its water supply from the Carlsbad desalination plant for the next 30 years. The plant produces 50 million gallons of drinking water – enough for around 400,000 people – every day and is by far the region’s most expensive source of water.

“In round terms, it’s twice as expensive as imported surface water,” Hanemann said. “On the other hand, it’s a very reliable supply because it’s unaffected by drought and low river flows in northern California or Colorado.”

As these efforts materialized, demand steadily declined, even as half a million more people moved to San Diego. Statewide water shut-offs during the drought, more efficient showers, toilets and faucets, weed-pulling sheds, and the use of recycled water did what they were supposed to: significantly reduce water consumption per person. In 2020, San Diegans used 30% less water than in 1990.

Water officials, however, had not anticipated the next drop in demand and consistently overestimated the amount of water needed. Today, San Diego County says it’s no longer looking for more water, a stance some westerners might consider enviable. But they wouldn’t envy water tariffs.

Thanks to the sale of less water, San Diego County has increased its rates – by an average of 4% in each of the past five years – to cover fixed costs, including the San Vicente Dam and the desalination plant. These costs represent the lion’s share — about 90% — of the agency’s annual expenditures.

The price of water, Hanemann said, is largely determined by the infrastructure that transports and stores it. “You’re screwed if all of a sudden you’re supplying fewer gallons of water since your costs aren’t going down.”

“Water is a terrible business because we need to encourage people to use less of our product and charge them more when they do,” said Tom Kennedy, general manager of the Rainbow Municipal Water District, one of two water agencies trying to break away from the San Diego County Water Board.


Rainbow and Fallbrook, the other city whose agency is trying to source water from elsewhere, say it would give them access to cheaper water, although the potential savings are not yet known. A state agency is considering whether they can leave, with a decision expected by the end of the year. If their exit is approved, the next step would be a vote among the residents. Only if this vote passes can both districts leave.

At a recent public hearing, angry residents yelled at authorities about how long the process will take – and how much their bills will cost in the meantime.

Rural towns provide a stark contrast to San Diego’s constellation of beach towns and waterfront skyline. To the northeast of the city, steep, dry hills and vast canyons dot the landscape.

High water costs have hurt agriculture in Fallbrook and Rainbow, once the nation’s largest avocado producer. Between 2016 and 2020, Fallbrook lost nearly a fifth of its avocado groves, according to government records, due to urbanization and fallow groves.

Jason Kendall, a Rainbow farmer whose family took out their avocado plantations years ago, said growing the fruit without additional groundwater is a losing business.

“You just can’t be profitable buying district water and growing avocados,” said Kendall, who owns 350 acres (142 hectares) of cut flowers, which are widely grown in the area.


San Diego County water officials say water costs are rising for other parts of California and the West, even though desalination is less popular today than it was. was formerly. Recently, a California Coastal Commission denied Poseidon Water a permit to build another desalination plant that had been under construction for decades about 60 miles up the coast at Huntington Beach. The rejection came after years of opposition from environmentalists.

The rest of the state has work to do, San Diego County officials said, as climate change continues to intensify droughts and narrow rivers feeding California reservoirs and the Colorado River.

“There is no more cheap water available,” Kerl said.


The Associated Press receives support from the Walton Family Foundation for coverage of water and environmental policy. The AP is solely responsible for all content. For all of AP’s environmental coverage, visit

Previous Congress Explores Ways to Preserve Affordable Mobile Housing Supply - Action News Jax
Next Supply chain shortages weigh on PHL restaurant operations