California's last resort: Drink the Pacific

You can't see the desalination plant from the beach in Santa Barbara. It's a few blocks from the ocean, tucked between a sewage treatment center and the Pacific Coast Highway, and in any case it's not very big. Just a row of water tanks, a few powerful pumps, some office space and a mess of pipes.

For nearly 25 years, the desal plant has sat unused. That's about to change.

As nearby beachgoers swam, sailed and paddle boarded on an overcast morning last week, Santa Barbara officials showed off those tanks and pumps, describing their plan to turn seawater into drinking water. It'll be expensive: up to $40 million to bring the desal plant back online, plus $5 million per year to keep it running. Water bills are expected to increase by about $20 per month. And for all that money, the city will meet 30 percent of its water needs at best.

City officials say the drought has left them with no other choice.

"With a drought of this nature, there isn't really any water supply that's going to help us aside from desalination," said Joshua Haggmark, Santa Barbara's water resources manager. "For the time being, this is our supply of last resort."

Desalination is a simple concept: Pump water from the ocean, remove the salt and drink. Water-poor countries like Israel and Saudi Arabia rely heavily on desal, and as California's historic drought drags on, the promise of a nearly unlimited water supply lapping at our shores is increasingly tempting to many water districts.

As desalination's many critics will tell you, it's a lot harder in practice than it is in theory. For one thing, it's extremely expensive, as Santa Barbara residents will soon discover. It also uses massive amounts of energy, which can exacerbate climate change, and it's dangerous for marine life if not done carefully.

But despite those concerns, it's starting to become inevitable that California will get more of its water from the Pacific Ocean.

State officials are evaluating 15 proposed plants, from the Bay Area to Camp Pendleton in San Diego County. The largest desal plant in the Western Hemisphere will come online in Carlsbad later this year, providing water for 300,000 people in San Diego County at a cost of approximately $1 billion. Another plant proposed for Huntington Beach would be just as big.

Advocates tout desalination as a drought-proof water source. They argue that as California's population grows, and as climate change makes droughts more frequent and more severe, we'll need desalinated water more than ever.

"Obviously we've done tons in conservation, but we have to have enough water," said Sandy Kerl, deputy general manager of the San Diego County Water Authority, which is buying the water from the Carlsbad desal plant. "You have to have some base level of water. You can't conserve what you don't have."

Even desal's critics say the technology is likely to play a role in California's water future — eventually. For them, the question isn't whether the technology makes sense — it's whether it makes sense to start using it now, when there are so many cheaper, safer strategies for meeting our water needs. Those strategies include conservation and wastewater recycling.

"We really need to ask ourselves, what else could we be doing at lower cost?" said Heather Cooley, water program director for the Pacific Institute, an Oakland-based research organization. "We have to look at it within that sort of context, and see if there are options that provide the same benefits, but with fewer social and environmental costs."

Related: How does the Salton Sea fare as California confronts the drought?

This isn't the first time California has suffered from critical water shortages. Faced with a then-record-breaking drought in the early 1990s, Santa Barbara commissioned the state's largest seawater desalination plant, which produced nearly 6.7 million gallons per day.

But by the time the desal plant was finished, the drought was ending. As rain blanketed the state, Santa Barbara suddenly had easy access to cheap water, and it shut down the $35 million facility after just three months.

The city's experience mirrors that of Australia, where officials poured billions of dollars into six enormous desalination plants during the "Millennium drought" that started in the mid-1990s. By the late 2000s, when those plants started to come online, it seemed like the drought might never end.

But then it did, washed away by a series of torrential rains in 2010. Four of the continent's massive desal plants now sit idle, according to Sandra Kentish, a chemical engineering professor and desalination expert at the University of Melbourne.

"Virtually the day that we commissioned those, it rained heavily across most of the eastern part of Australia," Kentish said. "There has been a lot of controversy here about whether those plants should have been built."

Critics call Australia's experience a cautionary tale about the dangers of sinking money into desalination plants you don't absolutely need. They worry the same thing will happen in California, with taxpayers footing the bill for billions of dollars' worth of desal facilities that could shut down once the drought ends.

Advocates, though, see desalination as part of a longer-term solution to California's unsustainable water use. Climate change, they point out, is likely to result in more frequent and more severe droughts, and some scientists believe decades-long "megadroughts" could become increasingly common in the western United States. The state's population, which has more than doubled over the last half-century, will continue to rise.

The Carlsbad plant was first proposed in 1998, long before the current drought. The San Diego County Water Authority has been trying for years to diversify its water sources and reduce its reliance on imported water, and it sees the Carlsbad project as a natural step in that direction.

"Drought is a common thing. We didn't propose this plant as a knee-jerk reaction to the drought that is happening right now," said Jessica Jones, a spokesperson for Poseidon Water, which is building the Carlsbad plant. "Regardless of whether the drought continues, there is a need for water in California."

Santa Barbara officials expect their long-shuttered desal plant to reopen in late 2016. City policymakers haven't discussed whether to keep it running when the drought ends — or whether to use it at all, if the drought ends before next year — but Mayor Helene Schneider said it's a conversation they need to have.

"We know that one day this drought will end. We also know there'll be another drought into the future," she said. "So instead of going through this panic mode of reauthorizing and restructuring a desalination plant, should we think differently in terms of, 'Should desal be a part of a regular water supply for the region, even at a small level, when we're not in a drought?'"

The answer to that question could be determined by the shifting costs of obtaining water. Desalination has been getting cheaper as technology improves, and in California, importing water has been getting more expensive as supplies dwindle.

Haggmark, Santa Barbara's water resources manager, said the city pays about $300 per acre-foot of surface water, $800 per acre foot of groundwater, and $1,200 per acre-foot of recycled water. He expects desalinated water to cost between $1,300 and $1,500 per acre-foot — more expensive than other sources, but relatively close to recycled water.

San Diego County's desalinated water will be more expensive, costing about $2,000 per acre-foot and likely causing a $5 to $7 spike in average monthly water bills.

Officials in San Diego County and Santa Barbara say they aren't expecting a major backlash to higher water costs. But even in Australia — where the high costs of desalination have generated the most controversy — it's not yet clear whether the investment will pay off.

"My own feeling is that we will use (the desal plants). It's only a matter of time," Kentish said. "I still think it's a good investment, because of climate change."

The process for turning ocean water into drinking water is relatively simple.

Seawater is pumped into desal facilities through intake pipes snaking out into the ocean, before being filtered for sediment and other large solids. Usually, the water is then forced through special membranes in a process called reverse osmosis, removing the dissolved salt. Finally, the salty water that didn't make it through the membranes is dumped back into the ocean.

It's the high-pressure reverse osmosis step that requires enormous amounts of energy. In order to supply water to 300,000 people, the Carlsbad desal plant will require the equivalent of a 31.3 megawatt power plant operating around the clock — enough electricity to power nearly 40,000 average California households for a year.

Unsurprisingly, desalination is the most energy-intensive method of obtaining water in California, according to a 2013 report from the Pacific Institute. It uses more energy per gallon than even the State Water Project, a complex system of aqueducts that pumps water from the state's wet northern regions to its parched south.

That energy consumption is a big reason desal is so expensive. It's also an environmental red flag, as desal's critics are quick to point out. As long as California gets most of its electricity from burning fossil fuels — which it does — energy-intensive processes like desalination will contribute to climate change, exacerbating the water shortages that desal is supposed to help alleviate.

Desalination "keeps us moving in this cycle," said Matt O'Malley of San Diego Coastkeeper, which has opposed the Carlsbad desal plant. "We really need to get out of this water-energy cycle."

No one desal plant will have a noticeable impact on the climate. But if California goes all in on desalination, approving the 15 plants that have been proposed, desal could have a "pretty significant" impact on the state's overall electricity use, said Kelly Sanders, an engineering professor at the University of Southern California who has studied the energy-water nexus.

Even without widespread desalination, she noted, water accounts for a small but not insignificant slice of California's energy use. The State Water Project alone uses 2 to 3 percent of all electricity consumed in California, according to the U.S. Environmental Protection Agency.

"I think the drought is making a lot of people nervous, and it's very important that we plan for it," Sanders said. "At the same time, I think there's other modes of water conservation and water supply we could move to before really making desal available on the large scale."

Desal advocates note that the technology has become more energy efficient over time, and that it's likely to keep moving in that direction. Poseidon Water, meanwhile, has said it will study the feasibility of generating solar energy at the Carlsbad plant. Poseidon will fund projects that pull carbon from the atmosphere, offsetting the desal plant's energy-related greenhouse gas emissions.

Energy use isn't the only environmental problem with desalination. Pumping ocean water can kill marine life small enough to get through intake filters, and dumping desalination's extremely salty leftovers back in the ocean can prove similarly fatal.

In Santa Barbara, officials plan to install new intake screens with 1 millimeter openings, which should keep out most species. But fish eggs and larvae at the bottom of the food chain will still be sucked into the pipes, and local environmental groups fear ripple effects that could affect a wide range of species.

"We have a very rich fishing industry here in Santa Barbara, and the impacts to that are what we're mostly concerned about," said Kira Redmond, executive director of Santa Barbara Channelkeeper.

Santa Barbara plans to contribute $500,000 to projects that support small marine life. Poseidon Water, meanwhile, will fund wetland restoration projects that benefit marine species and ecosystems.

But for environmental groups, those kinds of projects are a sorry excuse for mitigation.

"Trying to make up for a lot of death somewhere else is not really mitigation," O'Malley said. "You want to cut down on that mortality in the first place."

The best way to do that, environmentalists say, is to build intake pipes beneath the ocean floor, using the sand as a natural filter to keep out marine life. Building "subsurface" intake pipes isn't physically possible along some parts of California's coast, but where possible, it should be the default, proponents say.

Subsurface pipes are more expensive than traditional "open ocean" pipes, but they're likely to become the norm in California. The State Water Resources Control Board is set to vote next month on new guidelines that would require regional water boards to determine whether subsurface intakes are feasible before approving desal plants with open ocean intakes.

Still, the new guidelines won't affect desal plants that have already been approved, including those in Santa Barbara and Carlsbad. Both plants will use open ocean intakes, although Santa Barbara plans to study the feasibility of subsurface intakes.

Desal's other environmental challenge is how to dispose of the salt. For every gallon of clean drinking water that a desal plant produces, there's as much as a gallon of salty water that must be returned to the ocean, even though it now has a far higher salt concentration than seawater — potentially deadly for many species.

In Santa Barbara, environmental advocates aren't too concerned about the brine, because the city plans to mix it with less-salty water from a wastewater treatment plant before returning it to the ocean. And the state water board's new desal guidelines will force all plants to dump their brine in a less harmful way than is currently required.

But even with stricter rules, desal won't become a silver bullet for solving California's water woes, said Claire Waggoner, an environmental scientist at the state water board who has worked on the new guidelines. While desalination "makes your water pie a little bit bigger," Waggoner noted, even the Western Hemisphere's largest desal plant will meet just 7 percent of San Diego County's water needs.

"It's a tool. If a water developer wants to use it, these are the rules that you should have. But we shouldn't be putting all our eggs in one basket," Waggoner said. "We're in such dire straits with the drought, we need to explore everything."

Even desalination's harshest critics say they aren't opposed to it entirely. The debate in California is centered on questions like when we should turn to desal and how much water we should desalinate — and whether desalination makes any sense as a drought solution.

Desal's critics call the technology a distraction from cheaper, safer drought solutions, including conservation, efficiency, wastewater recycling and stormwater capture.

There's no question that Californians could be doing a lot more to save water, considering we haven't come close to meeting the 20 percent reduction target that Gov. Jerry Brown set last year. Brown announced mandatory 25 percent water cuts earlier this month, and some areas — including much of the Coachella Valley — will be required to reduce their water use by 35 percent.

"Really, the fundamental problem with (desal) is it doesn't force people to think differently about water," Redmond said. "And that's what we really need in California, is a cultural shift in the way we think about water, where we get it and how we use it. We need to understand, we don't need green lawns."

Advocates say it's never been their intention to portray desalination as an all-encompassing drought solution, and that conservation is critical with or without the technology. In Santa Barbara and San Diego County, officials say that even with further water cutbacks, they'll still need seawater to help meet their needs.

But for critics, it's hard not to see desal as a deceptively simple solution to an incredibly difficult problem. Policymakers and water users might be tempted to slack off on conservation and efficiency if the state moves too quickly to adopt desalination, they argue.

"There is a real concern that by building desalination plants, it does reduce pressure to develop cheaper options," Cooley said.

Even if Californians reduce their water use by 25 percent, though, it's still likely that more desal plants will be built — at some point. Sanders believes that while California doesn't necessarily need desal, a water future without it "would require such severe lifestyle changes that I think desal is going to be part of the equation."

Skeptics also point to wastewater recycling as an option that California should pursue before resorting to desal.

Purifying sewer water is less expensive than desalination, and it also eliminates the need to dump wastewater in the ocean. But right now California recycles just 13 percent of its wastewater, according to a report from the Pacific Institute and the Natural Resources Defense Council.

Orange County runs the state's best-known wastewater recycling system, which can produce up to 70 million gallons of high-quality water every day. That water is used to recharge Orange County's groundwater basin, which in turn is tapped for drinking water and other uses.

The main barrier to that type of wastewater recycling — known as indirect potable reuse — is cost. The Valley Sanitary District, for instance, operates a wastewater treatment plant in Indio, but it doesn't purify water thoroughly enough for human use, and officials have yet to find funding to upgrade the facility.

But in some parts of the state, groundwater basins aren't suitable for large amounts of indirect potable reuse. That's the case in Santa Barbara, where officials are interested in putting recycled wastewater directly into drinking water reservoirs — a process known as direct potable reuse.

The problem is that the state water board doesn't currently allow direct potable reuse, and it isn't likely to start anytime soon. The main concern is that recycled water could make people sick if not filtered through a groundwater basin first.

An expert panel is currently investigating whether direct potable reuse would threaten public health, but its recommendations aren't due to the state water board until the end of 2016. Even if the panel issues a positive report, the water board would then need time to adopt regulations.

But some experts say we have little reason to worry about public health risks.

"I think most people would tell you that the technology is at the point where (direct potable reuse is) completely safe," Sanders said. "But we're very risk averse."

Officials in Santa Barbara hope the state water board will speed up its timeline. So do officials in San Diego, which is working on a recycling system that could provide one-third of the city's water supply by 2035.

"Now that the drought needs are prevalent, will they speed the process up?" asked Alma Rife, a spokesperson for San Diego's public utilities department. "I'd really like to know the answer."

Nobody knows exactly how much water California could produce through desalination, if the state were to embrace the technology. Experts say much of the state's coastline wouldn't be suitable for desal plants, due to earthquake risks, environmental conditions and rising sea levels caused by climate change.

And in the meantime, it's no sure bet that the 15 facilities currently being considered will ever be built. Desal plants go through an arduous approval process, with permits required from up to half a dozen agencies, including the California Coastal Commission, the State Lands Commission, and the appropriate regional water board.

Some of the pressure to build more desal plants might come from out of state. The Southern Nevada Water Authority, for instance, considers desalination an important piece of its long-term water plans, according to Colby Pellegrino, the agency's Colorado River program manager.

While those plans could involve pumping desalinated water from the coast to the Colorado River, a more cost-effective option would be some kind of water exchange between Nevada and California, Pellegrino said. Under one scenario, Nevada would help pay for a desal plant that would serve California residents, in exchange for the right to more water from the Colorado River.

Nevada has also had discussions with California and Arizona about more complicated arrangements, some of which would involve building desal plants in Mexico, Pellegrino said. Nothing is going to happen anytime soon, but what all of those possibilities have in common is the reality that there's only so much water in the Colorado River, the Southwest's primary surface water source.

"I don't think that anyone's looking to do desal and say, 'I'm going to take less of my Colorado River water,'" Pellegrino said. "People are looking to desal to meet future demands."

Sammy Roth covers energy for The Desert Sun. He can be reached at sammy.roth@desertsun.com, (760) 778-4622 and @Sammy_Roth.

How does desal work?

Removing salt from seawater is a simple if energy-intensive process. Here's a step-by-step description of one of the most common desalination methods.

Seawater is pumped in from the ocean through large intake pipes. There are two types of intake systems: "open ocean intakes," which critics say endangers marine life, and "subsurface intakes," in which pipes are laid beneath the ocean floor. The pumped seawater is run through basic filters, which remove sediment and other large solids. Chemicals are sometimes added for more purification. High-pressure pumps push the filtered seawater through special membranes, removing the salt in an energy-intensive process called reverse osmosis. For every gallon of clean water that a desal plant produces, there's as much as a gallon of extremely salty brine. The leftover brine is pumped back into the ocean, which critics say can kill aquatic species if not done carefully. Methods considered relatively safe include diluting the brine with treated wastewater before returning it to the ocean, and spreading it out rather than dumping it all in one place.

Source: Desert Sun reporting