Planning for Dry Times: The West Considers More Reservoirs and Aquifers
The San Luis Reservoir, shown in September, stores water for agricultural irrigation in the San Joaquin Valley in Central California but has had significantly low water levels during the drought. Some local water officials want to expand the number of reservoirs throughout the state. Terry Chea/The Associated Press
Read more Stateline coverage of how communities across the West are grappling with drought that’s worsening because of climate change.
SAN DIEGO, Calif. — As parched California receives much needed rain and snow this winter, some local water officials are calling on state leaders to invest in new infrastructure projects that will store freshwater for inevitable dry times to come.
The worst megadrought in 1,200 years is devastating the water supply in the Western United States. It’s drying up the Colorado River basin, a major North American river system, while also depleting reservoirs and underground aquifers and forcing communities to make drastic cuts to their freshwater use.
Western states can no longer rely on snowmelt and rain to supply their communities in a drier, more arid landscape caused by climate change, say water experts.
Environmental groups have called for increased conservation efforts, such as pushing people to limit watering of ornamental lawns and upgrade to more efficient appliances. And they want officials to invest more in wastewater recycling or desalination projects. But some local water officials in California and across the West see a massive opportunity in storing rainwater in new or expanded reservoirs and groundwater aquifers.
“We can’t just keep conserving our way out of this,” said Gary Arant, general manager at Valley Center Municipal Water District, which serves communities throughout San Diego County. “Our supplies are becoming less and less reliable, our population is growing, our economy is growing. We’re at a point where we need to make investments in the statewide water system.”
Arant is one of several dozen local water officials, along with cities and business associations, that are part of the Solve the Water Crisis statewide coalition. The group is calling on California leaders to invest more heavily in water infrastructure and better coordinate the response to the drought, including by creating new ways to store freshwater.
With .3 billion in new federal money designated for drought resilience nationwide, as part of the bipartisan infrastructure law Congress passed earlier this year, now is the time to make those investments, Arant argued.
But critics say the water shortage requires other solutions. Needed actions include water recycling, cutbacks, desalination, wetlands restoration and more efficient use, especially by agriculture, said Heather Cooley, director of research at the Pacific Institute, an Oakland-based think tank focused on water issues.
“Adding more to storage isn’t really doing much,” Cooley said. “It doesn’t create more water. We’ve really met our limits of traditional supplies.”
In recent years, the drought has meant less snow in the mountains of California. When that snow melts in the spring, it replenishes reservoirs statewide. But snowpack has been unreliable in this three-year drought.
Without snowpack, precipitation instead has come in the form of sporadic and brief periods of heavy rain and atmospheric rivers — regions in the atmosphere that carry water vapor that can drop massive amounts of precipitation. The West’s water systems were not designed to handle such intense downpours, said Andrew Ayres, a research fellow with the Public Policy Institute of California, a nonpartisan think tank.
But with the right stormwater capture projects, that water not only can be stored in above-ground reservoirs but also injected underground to recharge depleted aquifers, especially in agricultural parts of the state that have over-pumped to meet their needs, he said. Local water officials also can divert rainwater to recharge ponds, where the water will slowly seep underground.
“Our success in managing the really tough dry times is going to start depending more and more on how we manage the wet times,” he said. “Increasingly, we’re going to have to do more deliberate planning, not only for new projects, but effective management of existing projects to get ourselves set up for dry times that are coming in the future.”
Despite recent heavy snows in the Sierra Nevada Mountains, the past three years have been the driest on record in California. As of last week, 85% of the state is still in severe, extreme or exceptional drought conditions, according to the U.S. Drought Monitor, which is operated out of the University of Nebraska-Lincoln in partnership with the federal government.
With these ongoing drought conditions, the state cannot rest easy when it gets a brief reprieve of precipitation, said Kimberly Thorner, general manager of the Olivenhain Municipal Water District, which serves parts of San Diego County. The state must act now to invest in its water reserves, she said.
In October, U.S. Interior Department officials allocated $210 million throughout the West for new water infrastructure. This includes three projects in California that would raise dams and create a new reservoir off the Sacramento River that would capture rainwater. That new Sites Reservoir is set to break ground in 2024.
California lawmakers also have earmarked $8 billion in new water infrastructure over the next three years, which includes hundreds of millions for storage projects. The statewide water strategy, which Democratic Gov. Gavin Newsom released in August, outlines several ways the state could expand storage opportunities through a “streamlined” permitting process.
Thorner, who is also part of the Solve the Water Crisis coalition, applauds these commitments from federal and state officials. However, she said she will continue to press state officials to make historic investments in water infrastructure, including new or raised reservoirs.
“A plan is great, but we need action,” she said. “We need to do something different.”
Adding more reservoirs might be challenging, however. The most economical and effective sites already have reservoirs, said Jay Lund, vice director of the Center for Watershed Sciences at the University of California, Davis.
“Building new or expanded reservoirs is often expensive and provides much less water than people might think,” he said in an email to Stateline. “New reservoirs also often involve sizable additional environmental damages. So, calls for new reservoirs usually go unrequited.”
In lieu of new reservoirs, it has become more common throughout the West to instead store additional water as groundwater, pumping it into underground aquifers for later use, Lund said. This tends to be less expensive and more flexible during droughts, he said, adding that it is easier to permit.
Storage isn’t the issue, said Cooley, of the Pacific Institute. It’s the water supply. She points to the Colorado River basin, which provides water for Arizona, California and Nevada and has four times the storage capacity than the average annual flow of the waterway.
Lake Mead and Lake Powell, two of the country’s largest reservoirs, are dangerously low and are projected, by some estimates, to hit a water level known as dead pool in the next two years if conditions continue, officials warn. Dead pool refers to a water level too low to operate the electricity-generating turbines in the dam or to allow water to flow downstream.
In October, California, which takes in more Colorado River water than any other state, offered to cut back the amount it receives from the waterway starting next year.
Cooley said that water shortage requires Western states to look for nontraditional supplies, including conserving water, recycling wastewater, desalinating ocean and brackish water, fixing leaks in the water distribution system, replacing ornamental lawns and investing in more efficient home appliances, such as dishwashers and washing machines.
State and local water officials also should invest in restoring wetlands and forests, which act as natural conduits that flow rain into groundwater aquifers, Cooley said. Overall, there are millions of acre-feet of water in untapped potential, according to an April report from the Pacific Institute, which Cooley helped author.
California’s agricultural sector, which uses more than 70% of the state’s water supply, also needs to use that water more efficiently and effectively, she added.
But farmers already are feeling the pinch, said Mike Wade, executive director of the California Farm Water Coalition, a nonprofit that educates the public on the agricultural sector’s water supply.
Draconian cuts to water use are not going to sustain California farmers’ ability to feed the rest of the country, he said. Moving ahead with new water projects, such as the Sites Reservoir, is how the state should proceed, he said.
“They are the facilities of tomorrow that gives us flexibility in managing the resource that we have today,” Wade said. “Planning for scarcity, I don’t think, is the long-term solution for California.”
The uncertainty over state water actions leaves local water officials in a precarious position as they face potential cutbacks to water usage, possibly forcing them to limit residents’ intake, said Arant, at the Valley Center Municipal Water District.
“I’ve got my hand on the valve and my eyes on the horizon looking for rain clouds,” he said. “And if I don’t see rain clouds, I’m going to start squeezing the valve.”
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