How A Dying Lake In California Factors Into The Colorado River’s Future
The biggest lake in California is shrinking.
The Salton Sea occupies a hot, desert basin a short drive from the Mexico border and it’s been evaporating for years. From the air the lake is pear-shaped, bordered by an intense concentration of farms growing winter vegetables on its south end, and date palms, citrus and brussels sprouts to the north. It’s sustained by the Colorado River water that passes through these farms as irrigation before flowing into the 350-square-mile lake.
The fact the lake is disappearing isn’t a shock. Its ever-widening shoreline is tied to a deal billed as the single largest transfer of agricultural water to a municipal area in history. For at least 15 years, authorities in California have known this would happen.
And now, those authorities are facing an impending public health and ecological disaster. Dealing with that disaster is a costly endeavor, one with ripple effects far beyond southern California.
Farming the playa
Jessica Lovecchio points down to a few trucks, parked near the Salton Sea from the top of a jagged hillside. This used to be a functioning marina. There’s even an old boat ramp that now empties into a dusty reach of land, hundreds of yards from the water.
A few hundred acres of dry, dusty shoreline — known as “playa” — stretch out in front. On a windy day, the dust would have made it impossible to make out the sea, Lovecchio said. She’s in charge of air quality projects for the Imperial Irrigation District or IID.
“This is our surface roughening and vegetation enhancement project,” Lovecchio said, gesturing toward the shore.
The IID is the single largest user of the Colorado River’s water. Use is measured in acre-feet, or the amount of water it takes to fill one acre up to a foot high. The entire state of California is entitled to 4.4 million acre-feet of Colorado River water each year. Of that, IID has rights to 3.1 million acre-feet.
Lovecchio’s crews are using some familiar farming equipment, but they’re doing a different kind of agriculture. They’re plowing up the shoreline, chasing the water line as it recedes in an attempt to tamp down its dust.
“So any dust that is being picked up off the surface right here hopefully it’ll fall into a furrow a few feet away,” Lovecchio said.
The dust is so bad it has killed crops and aggravated asthma for residents of this valley.
The lake’s origin story — and the story of its toxic dust — sounds like one borne of dystopian fiction. An engineering mishap in 1905 caused the entirety of the Colorado River, then being diverted to irrigate farms, to spill into a desert basin for a year and a half before being put back in its banks.
Since its inception, the Salton Sea has acted as an agricultural sump, meaning the runoff from tens of thousands of acres of irrigated farmland nearby ends up in the sea. Its makeup has been described as “dynamic,” constantly changing depending on the amount of rain, the time of year and the concoction of farm chemicals being used. A mix of salts, selenium, and fertilizers give the sea its potent smell, which began to drive tourists away after its heydey in the 1950s and 60s.
Today, the Salton Sea is nearly twice as salty as the Pacific Ocean and as it recedes, it’s getting saltier. As a result, some fish species have vanished, starving the migratory birds that stop there. The lake acts as a critical stopover along the Pacific Flyway, a veritable desert oasis for hundreds of bird species as they make their way along the coast.
“This Salton Sea serves two purposes,” said Luis Olmedo, director of the non-profit Comite Civico del Valle, founded by local farmworkers with a focus on environmental justice. “It’s become a man-made ecological treasure, as well as become a man-made ecological problem.”
The valley’s air frequently fails to meet federal standards, Olmedo said, and a shrinking Salton Sea is only going to make it worse.
“Every inch of water that is removed from this sea is exposing a hazardous waste landfill,” he said. “That is a big threat to our community.”
How Did We Get Here?
Michael Cohen said the lake’s decline can be traced back to an agreement between the San Diego County Water Authority and the Imperial Irrigation District, along with other water management agencies. Cohen is a senior researcher with the Pacific Institute, a water think tank.
“Back in 2002 and 2003, there was an understanding that taking water from IID meant as IID becomes more efficient, less water flows to the Salton Sea,” Cohen said.
As the district sells more and more water to San Diego, in exchange for irrigation upgrades for its farmers, water that was keeping the lake full is redirected toward bathroom faucets on the coast.
“Which means the Salton Sea shrinks — which is exactly what we’re seeing,” Cohen said.
But until late last year, the lake’s decline had been slowed. As part of that deal, the Imperial Irrigation District fallowed additional farmland and used that saved water to boost the Salton Sea. It was referred to as “mitigation water,” and was meant to give a 15-year buffer for the 2003 deal’s parties to figure out how to conduct and pay for restoration projects as the lake receded.
The mitigation water stopped flowing into the Salton Sea at the end of 2017 and Cohen said it will now begin a precipitous decline. In a 2014 study, Cohen estimated the lake losing 60 percent of its volume and tripling its salinity by 2030, leading to widespread algal blooms and more than 100 square miles of exposed playa.
But Cohen said there’s been a slow — or in some cases nonexistent —response to the lake’s decline.
California recently adopted a 10-year plan to address some of the problems at the Salton Sea, but not all of them, according to Bruce Wilcox, the state’s Assistant Secretary of Salton Sea Policy.
“One of the first things we recognized is that there are two issues going on here,” Wilcox said. “One is a longer-term issue of what is the sea going to look like in 20 years, 15 years, and the other is the fact that we are woefully behind in implementing anything.”
That means Wilcox had to split his priorities, and shift focus to short-term projects to create habitat for fish and birds by redirecting agricultural runoff into some of the exposed playa. The state plan doesn’t rule out some more ambitious proposals to keep the Salton Sea alive, like importing seawater from the Gulf of California.
But because of demands for Colorado River water is increasing, Wilcox said the river is not a place to look for solutions for the Salton Sea’s woes.
“There is no Colorado River water to spare,” Wilcox said. “Every place is looking for more water from the Colorado River and there isn’t enough to go around.”
A Watershed-Wide Problem
The Salton Sea’s accelerating decline comes at the same time that water scarcity in the entire Colorado River Basin is fueling negotiations over the river’s future — and how much states, cities and farmers will have to cut back if the Southwest’s 18-year drought continues. Those negotiations are part of a process to create a new agreement called the Drought Contingency Plan.
The Imperial Irrigation District sees Salton Sea restoration as essential and wants assurances that it is not alone in paying for the problems the shrinking lake creates. The state’s 10-year plan is unclear about how it will pay for the entirety of restoration projects needed, which could surge past a billion dollars.
Before the release of last year’s 10-year plan, IID officials said the lack of action at the Salton Sea made it impossible to come to the table and negotiate future cuts to Colorado River water deliveries to California, Nevada and Arizona under the Drought Contingency Plan.
“Look, the Salton Sea is a critical part of broader Colorado River negotiations,” said the Pacific Institute’s Michael Cohen. “IID was pretty clear that IID couldn’t participate in the Drought Contingency Plan without assurance there was some activity at the Salton Sea.”
The state’s 10-year plan placated some of those concerns, but Cohen said the state has yet to begin any on-the-ground projects.
This is all made more complicated by a recent court decision that forced IID to end a program that had allowed it to equally distribute and cap the amount of water its members receive, leading to even more uncertainty about the district’s ability to participate in negotiations.
That’s compounded by Arizona water officials having their own intrastate battles over the Colorado River.
Back on the sea’s shoreline, the Imperial Irrigation District’s Jessica Lovecchio and others have adopted the phrase “smaller but sustainable” to describe the Salton Sea’s future.
In that motto, there’s a resignation that the lake will never be what it once was.
“I’m from the Imperial Valley,” Lovecchio said. “I grew up here, so it has a special place in my heart. I would like to see it as a place that I can bring my kids, future grandkids to come and enjoy.”
Lovecchio’s plan depends on the ability to manage the lake’s decline, a responsibility that’s not just limited to the Imperial Valley, but the entire Colorado River watershed.