Ringside: The Economics of Managing Mono Lake

Along with the California Condor, one of our state’s most magnificent environmental success stories of the 20th century is how Mono Lake was saved. In the early 1980s, after decades of unsustainable water withdrawals from the Owens River into the Los Angeles Aqueduct, the lake had declined in elevation to 6,372 feet. The decline was primarily caused by the Los Angeles Department of Water and Power diverting an average of 80,000-100,000 acre feet per year from the tributaries feeding Mono Lake. The turnaround has been incredible.

Today, LADWP’s average withdrawals from the upper Owens River watershed are down to 16,000 acre feet per year. The level of the lake has risen to an elevation of 6,383 feet, which is within 9 feet of the what the State Water Resources Board has set as the ultimate goal of 6,392 feet. The acute crisis is over. For example, Negit Island, an important rookery where a land bridge was forming due to the dropping lake level, now remains safe from predators. And overall, years of investment in habitat restoration have preserved and enhanced one of North America’s most productive stopovers on the Pacific Flyway, supporting millions of migratory birds.

Moreover, according to a hydrologic model developed by LADWP, Mono Lake is on track to achieve an elevation of 6,392 feet within the next 22-26 years But despite this progress, the State Water Resources Control Board is in the early stages of reconsidering LADWP’s water diversion limits from the upper Owens Valley tributaries feeding Mono Lake.

On March 17, 2026, the SWRCB held an informational meeting to review a new hydrologic model, commissioned by the board and produced by UCLA’s Center for Climate Science. In the report’s “key findings,” the authors state that “Existing export criteria are unlikely to achieve Mono Lake’s long-term water level goals.”

This claim rests primarily on a concern that climate change may exacerbate conditions on the lake, and uses this reason to call for an immediate halt to any further diversions. But LADWP’s rights to their remaining 16,000 acre-feet per year are already required to drop to 4,500 acre feet per year if the lake level falls below 6,380 feet in elevation. And as it is, just evaporation from the lake averages 160,000 acre-feet per year, ten times the amount LADWP currently diverts.

It is reasonable to want to optimize the ecological health of Mono Lake. But the cost of precipitously cutting off LADWP’s last 16,000 acre feet from the upper basin must be taken into account. LADWP imports water from three sources, each of them with different salt contents. Mineral rich water from the Colorado Aqueduct has a high salt content, averaging 600-650 mg/L, whereas water from the Los Angeles Aqueduct, fed by the Owens River, along with water from the California Aqueduct, averages closer to 250-300 mg/L, only half as much.

This means that to deliver water to faucets in Los Angeles at a safe standard of around 400 mg/L, for every acre foot of water coming from the Owens River, LADWP is able to blend and therefore dilute an equal amount of the saltier water from the Colorado River. If LADWP loses 16,000 acre feet per year of water from the Owens Valley, the impact on supply is therefore 32,000 acre feet.

Advocates for cutting off LADWP’s last 16,000 acre feet of supply from the upper Owens Valley claim the city is on track to make up that difference through projects to recycle wastewater. That’s true, but the current cost per acre-foot of recycled wastewater is $2,500 per acre foot. What is at stake for LADWP, and the ratepayers they serve, is an additional cost of $80 million per year.

If LADWP were awash in investable profits, and water were falling from the sky in uncharacteristic and sustained abundance, it would make complete sense to go the last mile toward optimizing the greater Mono Lake ecosystem. But they’re not. Cash strapped and compelled to treat water to unprecedented new standards to cope with PFAS, the rates LADWP must charge customers are scheduled to nearly double in the next ten years. There is not $80 million available for LADWP to cover the shortfall.

In a March 13, 2026 letter to SWRCB chairman Joaquin Esquivel, LADWP CEO Janisse Quinones pointed out how their customers had lowered their water use by 33 percent over the last 15 years. This achievement cannot be overemphasized, and it applies statewide. According to this study from the Pacific Institute, urban water use peaked around 2004 at nearly 10 MAF (million acre feet)/year, with most recent data putting that total under 8 MAF/year despite the state’s population (94 percent urban) over the past 20 years growing by 3.8 million. Conservation has delivered big results, and it has gone far enough. We need to rehydrate our cities, not squeeze them dry.

There is a bigger picture that might inspire anyone hoping to rescue nature from the worst consequences of industrial civilization. Imagine if investments in infrastructure permitted fish friendly, safe harvesting of the massive storm runoff that tears through the Sacramento-San Joaquin Delta every winter. This would deliver millions of acre-feet of additional fresh water to farms and cities in Southern California. Imagine if through ongoing, hopefully accelerated investment in wastewater recycling, but also enhanced urban runoff harvesting and large scale seawater desalination, California’s coastal megacities wouldn’t even have to import water any longer. This is a vision that facilitates multiple environmental wins – including not just Mono Lake, but the Salton Sea and Hetch Hetchy Valley.

Finally, posturing over the sacred nature of Mono Lake – or any other ecosystem – whether animated by indigenous animism or new age spirituality, should not dominate the moral arguments put before the State Water Resources Control Board. These regulators also have a moral and sacred obligation to optimize the flourishing of all human beings, of all origins, whether living in cities or under the sky.