Southern California Prepared for Drought With Metropolitan Investments in Storage, Conservation, Diverse Supplies

Despite critically dry conditions across the state, Southern California can count on a reliable water supply thanks to residents’ enduring conservation efforts and the Metropolitan Water District’s investments in storage and diverse supplies, agency officials announced today in advance of tomorrow’s state snow survey.

The state Department of Water Resources snow survey is expected to provide the latest evidence that precipitation totals this year in the Sierra Nevada are far below average. The survey comes on the heels of DWR last week dropping the State Water Project water supply allocation from 10 percent to just 5 percent of contracted amounts, matching the record-low allocation recorded just six years ago.

The supply cut means Metropolitan will likely receive less than one month’s usual supply of water this year from the state project, which on average provides about 30 percent of Southern California’s water supply, Metropolitan General Manager Jeffrey Kightlinger said.

“In the long term, this is an alarming trend. And it’s what we have expected from climate change,” Kightlinger said. “The droughts are going to be drier. The peak storms are going to be stronger. The whole weather system is going to be flashier, much more volatile.”

Metropolitan is managing through such volatility by taking advantage of wet years, like 2017 and 2019, to move as much water into storage as possible. The agency has increased its total storage capacity by 13 times since 1990, investing in surface and groundwater storage across the southwest.

Not only has Metropolitan built vital infrastructure, such as Diamond Valley Lake and the Inland Feeder pipeline, which allow surplus water to quickly be stored in local reservoirs, it also has forged partnerships with water agencies across California for groundwater banking and exchanges. And it collaborated with partners along the Colorado River to establish a program to store water in Lake Mead, known as Intentionally Created Surplus, to enable Metropolitan to provide a full Colorado River Aqueduct supply in dry years like 2021.

Taken together, Metropolitan now has more water in these storage accounts than it ever has before – a total of 3.2 million acre-feet. An acre-foot is the amount used by three typical Southland households in a year.

Kightlinger said this record reserve has been made possible, in part, because of reduced water use across the region that has continued since the 2014-2016 drought. During that drought, widespread conservation initiatives encouraged Southern Californians to make conservation a way of life. Residents replaced water-thirsty grass with California native and California Friendly™ plants, installed water-efficient devices and appliances, and embraced a water-conservation ethic that endures. Per capita potable water consumption dropped from more than 150 gallons a day in the years before the drought to an average of about 120 gallons a day last year.

Metropolitan’s diverse water supply mix also means that when the Sierra Nevada is critically dry and SWP supplies are slashed, the agency can turn to its Colorado River supplies to help make up the difference. However, while the Colorado River can provide immediate relief, its long-term water supply outlook is also becoming significantly more constrained by the impacts of climate change and drought conditions that have stretched beyond 20 years.

“The good news is, we have enough water to get through this critically dry year. We’ve been preparing for droughts like this. We have sufficient water in storage, Southern Californians have done a great job conserving, and the Colorado River provides a sort of insurance,” Kightlinger said. “But in the long run, we have to do much more to get prepared for the impacts of climate change. All of California’s sources of water are facing serious long-term challenges.”

Statewide, more investment is needed in projects to capture and store water when it is available, such as the Delta Conveyance Project, which would more sustainably move water across the Sacramento San Joaquin Bay-Delta. Such efforts are critical to help the state adapt to the emerging impacts of climate change, where average snowpack will be dramatically reduced and precipitation will fall in increasing large rainstorms, Kightlinger said.

Greater investment is also needed to drought-proof local water supplies, such as Metropolitan’s Regional Recycled Water Program, he added.

And on the Colorado River, the Basin-states and water agencies must continue to work collaboratively to ensure the river’s long-term sustainability as they begin their next round of negotiations to develop new guidelines and agreements later this year, he said.

The Metropolitan Water District of Southern California is a state-established cooperative that, along with its 26 cities and retail suppliers, provide water for 19 million people in six counties. The district imports water from the Colorado River and Northern California to supplement local supplies, and helps its members to develop increased water conservation, recycling, storage and other resource-management programs.

Note: Video clips of General Manager Jeffrey Kightlinger and b-roll footage are available here.