Mono Lake not rising on schedule

Low lake vulnerable to drought & climate change; rule changes needed to accomplish lake protection

On a warm fall day in 1994, I walked into the state capitol building alongside a crowd of Mono Lake advocates. We assembled in a distinguished hearing room beneath an epic mural depicting California history to watch the California State Water Resources Control Board vote on their momentous revision of the Mono Basin water rights of the City of Los Angeles.

When we entered, those rights allowed unrestricted water diversions from the tributary streams that feed Mono Lake, restrained only by court orders won by the Mono Lake Committee and allies.

When we walked out a few hours later, those water rights had been transformed. No longer would the Los Angeles Aqueduct carry water away—indeed, entire creeks and streams—without regard to the destructive impacts on Mono Lake, its millions of migratory and nesting birds, and miles of stream habitat and rare wooded wetlands. In the new world that was launched that day, the health of the lake and streams became as important as the benefits of supplying water to Los Angeles.

That day State Water Board member Marc del Piero proclaimed, “today we saved Mono Lake.” The Board had voted unanimously to halt the lake’s diversion-induced decline and to mandate that Mono Lake rise to the sustainable long-term management level that the people of California and Mono Lake enthusiasts throughout the world have been waiting for ever since.

But today, in 2021, that healthy lake level remains frustratingly out of reach. The Board designed a 20-year transition plan that would swell the lake’s volume by 785,000 acre-feet of water and raise its level the 17 vertical feet needed to achieve ecological sustainability at a lake level that fluctuated around 6392 feet above sea level. Now, even after allowing an extra seven years for that transition, the lake is less than 40% of the way to 6392′. In fact Mono Lake is 11 vertical feet short of the goal, showing that the lake is far from recovering from decades of excessive water diversions.

The low lake is a problem of great concern, leaving danger looming over the unique ecosystem, the future of millions of migratory and nesting birds, and public enjoyment and health in this special place. In fact, the lake is expected to drop lower in this drought year, putting gull nesting islets in potential peril in 2022.

Fortunately, even in a time of hydroclimate extremes and accelerating climate change, the problem can be addressed with advocacy and action, in part because the State Water Board anticipated back in the 1990s that precipitation and runoff might arrive differently than their model projections of the time expected.

A sign at the County Park boardwalk marks 6392 feet above sea level, Mono Lake’s management level, but the lakeshore is still distant. Photo by Elin Ljung.

Standing at the edge of a cliff

A visit to Mono Lake today is a delight, where birds flock overhead and tufa towers rise from brine shrimp-filled waters. But like standing at the edge of a cliff on a windy day, things are fine until a gust of wind causes catastrophe. The risks of letting Mono Lake linger at low levels are large, as there is little buffer against dry-year elevation drops causing both swift and long-term ecosystem damage and increased violation of air quality standards. The smart move is to pull back from the brink.

The mandated management level pulls Mono Lake back from catastrophe. When Mono Lake rises to that level, the lower salinity will ensure a productive lake ecosystem of brine shrimp and alkali flies, which in turn provide plentiful food to millions of migratory and nesting birds that depend on the lake. The lake will be high enough to ensure a protective watery moat around the island-based California Gull nesting colony, one of the three largest in the world. It will be high enough to submerge thousands of acres of currently exposed lakebed, ending the emission of toxic dust that rides the wind and currently violates the Clean Air Act and makes Mono Lake the largest source of PM10 air pollution in the United States.

The lake at 6392′ will be high enough to be buffered from the ravages of multi-year droughts and the extreme dry-year swings forecast to increase with climate change. Even though the lake will still be 25 feet lower than it was when Los Angeles Department of Water & Power (DWP) diversions began, the lake’s many values—mandated for protection by the state Supreme Court in groundbreaking litigation brought decades ago by the Mono Lake Committee and National Audubon Society—will be protected. Those values include a healthy lake ecosystem. And all of us who love Mono Lake can rest easy knowing that our grandchildren will have a chance to see tufa towers through clean air at sunset, watch thousands of phalaropes in flight dipping and turning in unison, and experience all the wonders of a living, thriving Mono Lake.

In 1994 the State Water Board mandated that Mono Lake rise 17 vertical feet in order to achieve ecological sustainability. But today the lake is less than 40% of the way to 6392′. The current low level leaves Mono Lake, millions of migratory and nesting birds, and human health at risk, especially during the current drought. Because the lake is not rising on schedule, the State Water Board will consider modifying DWP’s water exports to ensure that the lake returns to health. Mono Lake Committee graph.

Saving Mono Lake

In 1994 the State Water Board acknowledged that its transition plan to raise the lake in about 20 years could be thrown off schedule by actual climate and hydrology in the years following the decision. They wisely put a date two decades later, in 2014, onto the calendar and said that if the lake had not risen as expected, they would hold a hearing to see if the water exports allocated to DWP might need adjusting to solve the problem.

In other words, the State Water Board’s lake protection requirement would not change over the years, but the rules for achieving it might.

The slower-than-expected lake rise scenario, unfortunately, has materialized. And the Board’s once-distant calendar date passed nearly seven years ago. On that day, the lake stood 12 feet below the management level, and the Committee agreed to give the lake six more years to climb out of drought. Yet last fall, on the sunny morning of September 28, 2020, the lake stood at 6381.5 feet above sea level, still more than ten feet below the expectation we had back on the same day in 1994 when we watched the Board mandate a healthy lake level requirement.

The timing of the hearing has not yet been set, but Committee preparation is well underway. Updating the lake level forecast model, for example, is essential to providing the analysis needed to consider new rule scenarios, and the Committee team has years of intensive work already complete.

There are also collaborative paths to explore. The goal of raising and managing Mono Lake at the healthy 6392-foot level is endorsed by everyone from air quality regulators to land management agencies to fellow conservation organizations to the Mono Lake Kutzadika’a Tribe to DWP itself.

DWP’s vast water diversions in the last century drove Mono Lake down 45 vertical feet and pushed the ecosystem to the edge of a cliff. But with concerned citizens raising the alarm, the State Water Board changed the outlook for Mono Lake and charted the path to a sustainable future that returns the lake and its birds and wildlife to health. All we have to do is follow that path. It is in everyone’s interest to step back from the brink by raising Mono Lake to the mandated healthy level. Now, 27 years after the State Water Board took action, it is more urgent than ever.

In 1994 the State Water Board mandated that Mono Lake rise 17 vertical feet in order to achieve ecological sustainability. But today the lake is less than 40% of the way to 6392′. The current low level leaves Mono Lake, millions of migratory and nesting birds, and human health at risk, especially during the current drought. Because the lake is not rising on schedule, the State Water Board will consider modifying DWP’s water exports to ensure that the lake returns to health.

This post was also published as an article in the Summer 2021 Mono Lake Newsletter. Top photo by Bartshe Miller.