In summary
LA had planned to take substantially less from the iconic Eastern Sierra lake this winter. The decision is a blow to conservationists who have been trying to restore the lake for decades.
Los Angeles will take most or all of its allotment of water from Mono Lake through March, disappointing local environmentalists and conservation experts after raising hopes that more water would be left in the iconic alpine lake.
The Los Angeles Department of Water and Power had indicated last spring that it might, in a rare move, substantially reduce the amount taken from Mono Lake. The Eastern Sierra lake has provided water to Los Angeles since 1941, when DWP began diverting its tributaries to city taps.
Known for its unique tufa rock towers, migratory birds and stunning Sierra nevada backdrop, the salty lake has been the focus of environmental battles for more than 80 years between the city, conservationists and the local Kutzadika’a tribe.
Mono Lake’s surface levels have plunged over the decades becuase of the city’s aqueduct, hitting historic lows in the 1980s and increasing the lake’s salinity, which jeopardizes the tiny shrimp that are the major source of food for birds.
In July,the lake,rising from excessive snowmelt,hit its highest level in 17 years but is now dropping. A state goal set in 1994 aims to restore the surface to an elevation of 6,392 feet — a target that is currently 9 feet away.
Last May, DWP reached out with an apparent olive branch: In its annual operating plan for the Mono Basin, the department indicated it could take only 4,500 acre-feet from the lake’s tributaries through March of 2025. That’s less than a third of the maximum 16,000 acre-feet that the city is legally entitled to take in a water year — enough to serve up to 200,000 Angelenos, or 5% of the city’s population.
“Planned export is 4,500 AF,” the report said, adding that after a review of conditions and storage, DWP would decide in November whether it would take its full allotment through the spring.
Environmentalists — who sent a letter last March to Mayor karen Bass requesting such a move — celebrated, saying it marked the possibility of a new path forward, and upward, for Mono Lake.
but six months later, in late November, the city’s diversions had already exceeded the 4,500 acre-foot mark.As of Jan. 29, DWP had taken more than 8,545 acre-feet from Lee Vining and Rush creeks, according to a live-tracker posted by the Mono lake Committee, the lake’s leading watchdog.
at that pace, the city will reach most of its full allotment by the end of march, when a new water year kicks in.
“Reducing diversions in the first place was a voluntary action…to show that we’re all working together…That’s what’s so disappointing that DWP said, ‘Yeah, we’re not going to do that.’”
Geoff McQuilkin, Mono Lake Committee
Adam Perez, DWP’s Los Angeles Aqueduct manager, said the rainless fall, which has continued in an alarming winter dry spell, factored heavily into the decision about how much water to take.
Voluntarily reducing water from Mono Lake runs counter to the water department’s operating directive. “We always try to maximize aqueduct deliveries to the city,” Perez said. That’s in part because water from the Eastern Sierra is one of the city’s cheapest supplies.
Perez said DWP had to “review current hydrological conditions, available storage within the aqueduct system and also environmental conditions” at Mono Lake and its tributaries.
DWP has taken less than its full annual Mono Lake allotment only twice, for operational reasons, said geoff McQuilkin, executive director of the Mono Lake Committee.
The decision is a deflating disappointment for McQuilkin, who has lobbied for the restoration of Mono Lake for more than 30 years.
“It wasn’t illegal,” said McQuilkin. “Reducing diversions in the first place was a voluntary action, but that was kind of the point — to show that we’re all working together … taking a collaborative approach forward, and that’s what’s so disappointing that DWP said, ‘Yeah, we’re not going to do that.’”
Water supply in Los Angeles has become a political flashpoint in recent weeks as President Donald Trump has repeatedly said that environmental rules limiting water exports from the Sacramento-San joaquin Delta reduced the amount available for firefighters.
That claim is false.
“More Mono Lake water wouldn’t have stopped that fire, and the Delta would not have stopped the fires,” said Bruce Reznik, executive director of L.A. Waterkeeper.
For months, Southern California’s water supply system has been nearly full, with large reservoirs at or near capacity. The lack of water in some hydrants during the Palisades Fire in Los Angeles was instead a local delivery problem — DWP’s pipelines failed to accommodate the sudden increased demand, losing pressure.
Water officials have rebuked Trump for misinformation about how California’s water supply system works. “Attempts to connect water management in Northern California to local wildfire fighting in los Angeles have zero factual basis,” Gov. Gavin Newsom’s Communications Deputy Director Tara Gallegos said in a statement.
Perez said most of the city’s water during the firestorms last month came from the Owens Valley and Mono Lake, “highlighting the importance of this foundational water source which proved critical for the LA’s water supply resiliency.”
LA gets only 1%-3% of its water from Mono Lake
Table of Contents
- LA gets only 1%-3% of its water from Mono Lake
- A state requirement to restore the lake
- LA is using less water and relying more on local supplies
- The Pillars of CalMatters’ Journalism
- A Call to Action: Supporting Independent Journalism
- Why CalMatters Matters
- The Pillars of CalMatters’ Journalism
- A Call to Action: Supporting Independent Journalism
- Why CalMatters Matters
- Interview with calmatters: Empowering California Through Independent journalism
- conclusion
Some 30 miles east of Yosemite Valley, vast amounts of Sierra Nevada snowmelt drain into Mono lake, which is more than a million years old. Twice as salty as the ocean because it has no outlet, the lake is home to brine shrimp that live nowhere else on Earth and millions of birds, including gulls, grebes, eagles and osprey, and also other wildlife. Its craggy limestone formations and bright blue waters are a favorite of photographers, including the late Ansel Adams.
In an infamous “water grab,” Los Angeles built its 233-mile aqueduct to the Owens River in 1913, draining the trout stream that provided the farm region’s water, and then extended it north to Mono Lake tributaries 28 years later.
“From an L.A. perspective and what we need on a day-to-day basis to thrive, that amount of water is very small, whereas for the recovery of Mono Lake, it’s incredibly important.”
Mark Gold,Natural Resources Defense council
Los Angeles’ 4 million residents consume about half a million acre-feet of water per year. Eastern Sierra water — mostly from the Owens River — makes up a variable portion of this total,from about 60,000 acre-feet in drought years to more than 300,000 acre-feet in wetter years.The rest of the city’s water comes from the Colorado River, the Delta and locally captured stormwater, recycled water and groundwater.
Mono Lake water amounts to only 1% to 3% of the city’s supply, depending on whether it’s a wet or dry year, according to DWP data.
That’s why some water policy experts and environmentalists think the city could minimize or entirely forfeit its Mono Lake water with negligible economic impact.
“We’re talking about 4,500 acre-feet versus 16,000 acre-feet,” said Mark Gold, water scarcity solutions director for the Natural Resources Defense Council. “From an L.A. perspective and what we need on a day-to-day basis to thrive, that amount of water is very small, whereas for the recovery of Mono Lake, it’s incredibly important.”
Jeffrey Mount, a geomorphologist and water supply expert with the Public Policy Institute of California, thinks Los Angeles could relatively painlessly sever its link to the Mono basin.
“Los angeles’ share of water that comes out of that system has steadily declined to the point that it’s such a small number now,” he said. “Maybe we need to rethink whether it’s worth it for LA to keep taking that water.”
“While Mono Lake water is critically important to the environment, it’s also very important to the city of Los Angeles.”
Adam Perez, Los Angeles Department of Water and Power
But Perez said that Mono Lake’s water, while a minute portion of the city’s entire supply, is prioritized partly because relinquishing it would mean buying additional water from more expensive sources, which could raise customers’ rates.
Eastern Sierra water delivered via the Los Angeles Aqueduct costs the city about $950 per acre-foot, while imported water from the wholesaler, the Metropolitan Water District of Southern California, runs about $1,240 per acre foot.
“While mono Lake water is important to the environment, it’s also very important to the city of Los Angeles,” Perez said.
A state requirement to restore the lake
by the early 1980s, 40 years after los Angeles began taking its water, Mono Lake had dropped 45 feet. Half its water was gone and its salinity had doubled.
With Mono Lake on track to disappear, environmentalists intervened in 1979, filing a lawsuit that challenged the city’s water rights. This led to a milestone state water board ruling in 1994 that set limits on how much water Los Angeles could take from the Mono basin.
the city’s maximum take is 16,000 acre-feet per year — but only if the lake’s surface is between 6,380 and 6,391 feet above sea level on April 1. If levels fall to between 6,380 and 6,377 feet, the city can take 4,500 acre-feet over the next 12 months. Below that,diversions are banned.
Stakeholders anticipated that the rules would achieve the 6,392-foot target elevation by 2014. But the lake has never risen more than a few finger widths above 6,385 feet. The problem appears to be the rules’ tiered system: Each time the lake recovers a few feet, it triggers the jump to full diversions so the lake shrinks again.
This has occurred several times, and the next dip in Mono Lake may be starting now. The lake’s surface has been dropping since August.
“If DWP takes the maximum allowable volume, we don’t get to the recovery level,” McQuilkin said.
Erik ekdahl, deputy director for the State Water Resources Control Board’s Division of Water rights, said the agency must consider all options and beneficial uses of the lake’s water. The board plans to hold a public hearing sometime this year; no dates have been set.
“What is a reasonable amount of diversion given LA’s water needs, given the public trust needs at Mono Lake, and the decision that was made in 1994?” Ekdahl said. “Do those interim diversion volumes still make sense,given where we are and the progress we’ve made and everything we’ve learned in the past 30 years?”
Climate change — especially more extreme droughts and warming winters with less snow — has probably disrupted the forecasted trajectory for Mono Lake’s recovery.
“When this target was ordered by the state water board, we didn’t know what the impacts of climate change would be,” NRDC’s Gold said. “This isn’t a finger-pointing blame game against DWP … the existing approach hasn’t reached the required lake level, and climate change has a heck of a lot to do with it.”
LA is using less water and relying more on local supplies
Los Angeles, like other Southern California communities, is ramping up its use of option water supplies. DWP plans to double its stormwater capture, to an annual average of 150,000 acre-feet, in the next 15 years. It also is ramping up water recycling with so-called “toilet-to-tap” treatment technology — technically known as direct potable reuse — newly permitted by state rules.
The goal is to shift the city to 70% local water by 2035.
The city has also drastically reduced its water use over time,despite a growing population. Between 2004 and 2020, the city cut its water demand by 29%. California cities are required to reduce usage under a new state conservation rule adopted last year.
To McQuilkin, these accomplishments plus the city’s diverse water portfolio are all the more reason for Los Angeles to relinquish, at least for now, Mono Lake’s water.
The city has “many sources of water and a long-range storage capacity to handle multiple dry years,” McQuilkin said. “Mono Lake has one.”
