In summary

The environmental costs of ending water diversions from Mono Lake to Los Angeles would be mixed: It might help a shore bird habitat but would require changes that increase carbon emissions.

California’s effort to secure water supplies is a struggle older than the state itself. 

It played out during the Gold Rush, and it defines modern San Francisco and Los Angeles. It has created divisions between north and south as well as east and west. It consumes endless political energy and mountains of literal energy, spent by moving water from the Sacramento Bay Delta to San Jose and Southern California, from the Colorado River to the Los Angeles basin, from the Sierra Nevada to the Bay Area.

In all of that, Mono Lake is a small data point, barely a dot on the state’s vast water map. So why is Mono Lake suddenly attracting attention in water circles? 

A coalition of environmentalists and Native American tribes – the Kutzadika’a Paiute have lived in the Mono basin for centuries – are fighting for that water, arguing that Los Angeles, which began diverting streams away from the lake in 1941, should give up its rights and let the lake be. That would allow Mono Lake’s surface level to rise, though it still would confront the more ancient problem of evaporation.

There’s a lot of history behind this struggle, as there is in all matters involving California water. And that early history does not reflect well on the Los Angeles Department of Water and Power’s stewardship of Mono Lake. After receiving its permits to draw water from the area in 1940, the DWP did so voraciously. The level of the lake dropped by 45 feet from 1941 to 1982. 

In 1994, the state water board put a halt to that, limiting the amount the DWP can take in any given year. In the years since, the lake has slowly rebounded, though its condition remains delicate.

Paradoxically, the argument for forcing Los Angeles to end its diversions from the Mono basin now rests largely on the fact that, since 1994, it hasn’t drawn that much water anyway. So, if it’s already prevented from taking more, why not stop drawing this water altogether? To advocates, that seems like common sense; to the DWP, it feels like being punished for having succeeded. 

In the big scheme of things, it’s true that the amounts that DWP takes from the Mono Lake basin are tiny (no water is drawn from the lake itself, since it’s briny; the DWP gets its water from four creeks that feed the lake). Today, the DWP withdraws no more than 16,000 acre feet a year, and it often takes much less than that. 

Compared to Los Angeles’ overall usage, that’s a pittance. The city consumes about 500,000 acre feet of water annually, so even in a big year, the water from the Mono watershed amounts to no more than about 3% of the total.

Still, that’s enough water to supply some 45,000 homes or as many as 200,000 people in the denser areas of Los Angeles (San Francisco, with its more tightly packed population and fewer gardens, stretches an acre foot of water to about eight households). 

Then there are the birds. Mono Lake is an important way station for migratory birds and a vital shorebird habitat. If the level of the lake falls too low, it exposes land bridges that connect the lake’s major nesting island to shore, allowing coyotes to dart across the bridge and disrupt the birds. That makes keeping the lake level high enough to preserve the islands an important priority. 

And yet, despite recent droughts – and even with the DWP’s diversions – the water has not fallen to the level that creates coyote bridges in decades. The level of the lake today is more than 10 feet higher than it was in 1981, according to the DWP. 

“There’s nothing even remotely like a land bridge out there now,” Martin Adams, the DWP’s general manager and chief engineer, said in an interview this week. 

On the issue of conservation, I asked Adams whether he would walk away from the agency’s water rights in the Mono Lake area if the DWP could find an additional 16,000 acre feet through conservation. 

His answer was simple: no.

The DWP’s first priority with conservation, he said, is to cut back on importing water from expensive, environmentally inferior alternatives. If suddenly granted a windfall, “we’ll purchase less water from the Metropolitan Water District,” he said. 

That makes good financial sense. Metropolitan water is expensive – about $750 per acre foot – because it has to be shipped, either from Northern California through the State Water Project or from the Colorado River, where other states and Native American tribes are fighting for their rights.

But it’s not just money. There are environmental ramifications as well, and Martin’s priorities make good environmental sense. Metropolitan water has to be shipped long distances, and as a result, it requires huge amounts of electrical power (water is heavy and very hard to move uphill). In fact, moving water from point to point is among the largest uses of electricity in California. 

Since generating electricity is one of the main contributors to carbon emissions, it’s bad for the climate to move water. 

“All of these resource decisions involve trade-offs. I’m not hearing the compelling argument in this case.”

Jeff Kightlinger, former general manager of the Metropolitan Water District of Southern California

By contrast, the Los Angeles Aqueduct, the genius project of William Mulholland, brings water to Los Angeles from Mono and the Owens Valley by gravity alone. In fact, it generates a bit of power as it flows south. That’s the opposite of spending energy to heave water over mountains from the Bay Delta or the Colorado.

So, financially, it does not make sense for DWP to cut off Mono Lake supplies. And the environmental costs would be mixed: It might shore up bird habitat that is not presently jeopardized, but it would do so at the expense of contributing to climate change.

I ran all of this by Jeff Kightlinger, former general manager of the Metropolitan Water District and one of California’s most highly regarded water experts. Kightlinger doesn’t have a dog in this fight. If anything, a decision by the DWP to abandon its rights to Mono Lake water would help Kightlinger’s former agency, since DWP might be forced to buy more water from Southern California’s giant importer.

Nevertheless, Kightlinger sympathized with the DWP on this one. 

Yes, he said, there are issues related to birds, but those mostly seem under control – no land bridges are endangering the nesting areas. And yes, there are gains to made in conservation, but Kightlinger agreed with Adams that it’s hard to see why the DWP would give up a clean water source in the eastern Sierra, where it gets water essentially for free, in return for spending more money and using more energy to buy it from Metropolitan.

“All of these resource decisions involve trade-offs,” he said. “I’m not hearing the compelling argument in this case.”

Could that change? Of course – if the lake levels begin dropping again, putting the birds in danger. Or, if prolonged drought meant that even the DWP’s modest withdrawals from the area’s creeks cut off the supply to the lake and it falls into a downward spiral.

If history is any guide, this fight will drag on for a long time. For the moment, a very wet winter has allowed it to not feel pressing. But it hasn’t gone away.

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Jim Newton is a veteran journalist, best-selling author and teacher. He worked at the Los Angeles Times for 25 years as a reporter, editor, bureau chief and columnist, covering government and politics....