DRIED UP: In California, desalination offers only partial solution to growing drought

The American West is experiencing its driest period in human history, a megadrought that threatens health, agriculture and entire ways of life. DRIED UP is examining the dire effects of the drought on the states most affected — as well as the solutions Americans are embracing.

As water in the Western U.S. becomes an increasingly rare commodity, the driest states are grasping at solutions for an even drier future — investing heavily in technologies to maximize the conservation, and creation, of the region’s most precious resource.

With more than a thousand miles of Pacific Ocean coastline, California appears to have access to a wellspring that other arid states lack. The technology to transform that unlimited sea supply into potable drinking water has existed for decades, through a process called desalination. Yet while two new desalination plants have received approvals in the past couple months, California’s coast isn’t exactly teeming with such facilities.

That’s because the technology, which is both expensive and energy intensive, can leave behind a mammoth-sized footprint on both surrounding communities and marine life, even as it helps quench the thirst of a parched citizenry. 

One of several necessary strategies

With little sign of reprieve for the region’s water woes, experts agree that desalination will continue to play a critical, although partial, solution to a crisis that promises to last.

“Our attitude on ocean desal is that it is a tool in the toolbox,” Garry Brown, founder and president of Orange County Coastkeeper, told The Hill in a phone interview this summer.

“But it’s a tool of last resort — after you have exhausted all your other options,” Brown continued. “Ocean desal, as we’ve learned it here, has the greatest environmental impacts, the greatest energy requirement and is by far the most expensive.”

Desalination is the process of removing excess salt from water, usually by means of a technology called reverse osmosis that separates water molecules from either seawater or salty brackish water found inland.

While the process generates potable drinking water, it also produces a high-concentration salt solution called brine that is usually discharged into a receiving body of water.

Arid nations such as Saudi Arabia, Israel and the United Arab Emirates have long relied on seawater desalination to make up considerable shares of their drinking water supplies despite its drawbacks.

“It’s almost romantic to think, ‘Let’s just stick a straw in the ocean and we don’t have to worry about water,’” Brown said. “But it’s far more.”

There are currently 12 desalination facilities in California, according to the State Water Resources Control Board. The biggest to date is the Carlsbad desalination plant, located just north of San Diego.

In mid-November, the California Coastal Commission in an 8-2 vote granted conditional approval for another desalination facility in the Monterey County city of Marina — this one hotly contested, CalMatters reported. 

The proposed facility would send supplies to richer enclaves adjacent to Marina, which has sufficient water but is also home to lower-income neighborhoods, according to CalMatters.

This project, which would still need to obtain a litany of permits, would face restrictions that seek to minimize its environmental and community impact, the state news site reported.

‘Much closer to being advisable’

Another facility, called the Doheny Ocean Desalination Project, has received much warmer reception from administrators and environmental activists alike — earning unanimous approval from the Coastal Commission in October. 

The project, initiated by the South Coast Water District, will be built within 100 yards of existing regional water transmission lines on property that the district already owns, a statement from the agency said. 

This $120 million facility will be situated on Doheny State Beach about 30 miles northwest of Carlsbad. The plant will serve customers from the South Coast Water District and southern Orange County — with a capacity of up to 5 million gallons per day, according to the district. 

The Doheny project has faced little opposition due to its relatively small environmental footprint and the unique technology it will employ. The facility will be withdrawing seawater from beneath the ocean floor in a way that optimizes the protection of marine life, according to the district.

The beach’s geography, as well as the lack of other water in that region, also make the spot much better suited for a desalination plant than other areas, according to Gregory Pierce, the co-director of the Water Resources Group at UCLA.

“That one is much closer to being advisable,” he told The Hill over the summer, prior to the plant’s approval.

Pierce was comparing the Doheny project to recently rejected plans for a massive plant in Huntington Beach, about 25 miles northwest of Doheny and just southeast of Los Angeles. 

The Coastal Commission rejected the $1.4 billion Huntington Beach proposal this past May after two decades of debate — citing obsolete protocols, inadequate risk mitigation strategies and violations of the California Coastal Act in their decision.

California Gov. Gavin Newsom (D) examines a cup of desalinated water while visiting the construction site of a new desalination plant in Antioch, Calif., Thursday, Aug. 11, 2022. (AP Photo)

Jack Ainsworth, executive director of the Coastal Commission, stressed in a statement at the time that the agency would “continue to support” desalination facilities “that comply with the law” and that the technology would remain “part of our current and future water portfolio.”

The costs of the project would have been “borne disproportionately by those who are least able to bear it,” Megan Harmon, a coastal commissioner from Santa Barbara, said at the hearing.

Stressing that all desalination projects must be cost-efficient and environmentally sound, Harmon said that the technology “must be and will continue to be a fundamental part of our state’s water portfolio.”

Following the Huntington plant’s rejection, Jessica Jones, director of communications for Poseidon Water, confirmed that Poseidon would not be pursuing anything else at that site. She noted, however, that the company is “in conversations with public partners throughout the state on different water projects.” 

Of the three recently debated projects — the rejected Huntington Beach site and the approved Doheny Beach and Monterey facilities — Monterey may be the best indicator of the future of desalination for California, according to Pierce, the UCLA water resources expert. 

The Coastal Commission’s decision on Monterey may be “somewhat of a referendum” on how the agency weighs environmental impacts versus near-term costs, Pierce told The Hill in a follow-up email last week. 

Water treated by desalination is poured into a glass for Gov. Gavin Newsom (D) and other government officials to taste during a visit at the construction site of a new desalination plant in Antioch, Calif. (AP Photo)

While all desalination projects have major environmental impacts, Monterey’s design — similar to that of Doheny — seems to fall on the less-damaging end of the spectrum, Pierce explained. At the same time, the cost per gallon of Monterey water is poised to be among the highest proposed thus far, he added.

Desalination might not rank among California’s top two or three solutions to the ongoing water crisis, but it will likely remain within the top five or seven, according to Pierce.

Conservation remains crucial

Preferable to desalination, he said, are tactics such as conservation, wastewater recycling and groundwater replenishment — in which treated wastewater is injected into an underground storage buffer, prior to releasing that water into a municipal system.

This practice, also known as “indirect potable reuse,” already occurs regularly throughout the state. A second process called “direct potable reuse” — discharging purified wastewater directly into water systems without an environmental barrier — is awaiting regulatory approval.

But as far as desalination is concerned, Pierce stressed that its use should be dependent on a given region’s water supply options.

While the technology might be suitable in portions of the Central Coast and San Diego, the same cannot be said for Los Angeles or parts of the Bay Area, which have diversified their water portfolios and ramped up recycling efforts, he said. 

Similar logic contributed to the rejection of the massive Huntington Beach facility, which would have been located in Central Orange County — an area “blessed with an enormous underground aquifer,” according to Brown, from Orange County Coastkeeper. 

Because that aquifer is almost two and a half times the size of Lake Mead, the biggest reservoir in the Colorado River basin, Brown said there could not have been “a worse place for a desal plant.”

Going forward, Pierce said he is optimistic that “the technology will get better for desalination, just like EVs and solar,” referring to electric vehicles and rooftop solar panels. As the technology improves, he explained, the price will become more affordable as a result.

The dismissal of the Huntington Beach project was likewise a testament to a case in which the technology simply wasn’t good enough to warrant the investment and potential ecological consequences, experts agreed.

Pierce reiterated his belief that the technology will continue to evolve, while emphasizing that desalination is by no means the sole solution to the Western water crisis.

“It’s not the only or best answer — period,” he said.

Previously in this series:

Threats to Colorado snowpack pose risks far downslope

Compounding fires and floods in Southwest pose dire threat to drinking water

In Utah, drying Great Salt Lake leads to air pollution

Texas cities in fear of running out of water

Lakes Mead and Powell are at the epicenter of the biggest Western drought in history

Seven stats that explain the West’s epic drought

Texas cattle industry faces existential crisis from historic drought

Why Great Plains agriculture is particularly vulnerable to drought

Five reasons extreme weather is bigger in Texas