Sea Quencher: Can California Assuage Its Drought Woes With the Pacific Ocean?

By Glen Martin

As the drought deepens and associated angst spikes, a variety of solutions have been bruited about our parched state: New reservoirs. Rigorous (even draconian) conservation. Recycling.  Hauling icebergs from Alaska.  Fervent prayer. 

And marine desalinization.

“Desal,” of course, is nothing new. Over the past 30 years, the notion of processing salty sea water into usable, drinkable “fresh” water has been both hailed as the ultimate solution for the Golden State’s water woes and condemned as pie-in-the-sky fantasy, a prohibitively expensive and ultimately insufficient response to any prolonged supply crisis. So what’s the truth? Somewhere between salvation and complete bust, it appears.

First, desalinization is by no means an experimental technology. It is widely used throughout the arid portions of the world, and is living up to (reasonable) expectations.

“Israel now gets about half its drinking water from marine desalinization,” says David Sedlak, the co-director of the Berkeley Water Center, a collaboration of experts on hydrology, resource economics, and water policy and engineering from UC Berkeley and Lawrence Berkeley National Laboratory. “Perth (Australia) also gets half its water from desal. This is no longer a technology just for wealthy Middle East sheikdoms and Caribbean islands with no other option. As more plants are built, companies have found ways to desalinate more water for less energy. It’s becoming viable for an increasing number of places.”

And a drought-ravaged California may just be one of those places, at least to a degree. Yesterday U.S. Sen. Barbara Boxer of California said she would push for millions of federal dollars into research on how to improve desalination technology. Indeed, the state has dabbled with desal since the early 1990s. Marin County had an experimental facility, and small desal plants are now in operation in Monterey and the Santa Cruz Islands. Santa Barbara built a desalinization plant during a drought that lasted from 1986 to 1991. Designed to churn out 3,125 acre-feet of fresh water a year, it operated for four months, then was shuttered when the rains fell in earnest. (An acre-foot is about 325,000 gallons, enough to supply two households annually). Now local officials are considering retrofitting and reactivating the plant.

But those facilities are mere drops in the bucket compared to the massive desalination plant that is scheduled  to open in Carlsbad this fall. It’s expected to produce 50 million gallons of water a day. Considering the average American consumes 100 gallons daily, that’s enough water to slake the thirst, flush the toilets and wash the clothes of 500,000 San Diegans.

Even at that production rate, White House science advisor John Holdren recently told the San Francisco Chronicle, it would take some 60 similar plants to meet half of the urban water needs of California. Still, he said, “it could be done.”​

Most desalinization plants employ reverse osmosis, a process that involves forcing seawater through special membranes to remove salt and other undesirable compounds. That takes a lot of energy and money. Currently, desalinated water costs about $2,000 an acre-foot, roughly twice the price of water obtained from reservoirs or recycling, and four times the cost of water “produced” through conservation.

Still, that represents a significant improvement from the plants of yesteryear.  Today’s plants consume only about a quarter of the electricity of their 1980s counterparts, and membranes are also vastly superior to earlier models.

“The membranes have gotten better over time, and people are also finding ways to recover energy during the desalinization process,” says Sedlak. “Each improvement yields about a 3 to 5 percent gain in efficiency. We’re now at the point where desalinization costs about the same as pumping water over the Tehachapis”  using California’s government water projects.

Still, desalinization’s costs aren’t all about dollars and cents. Desal plants can leave a pretty big footprint on the coastal landscape, the intake pipes can suck up larval fish, and there are concerns about disposing of the concentrated brine yielded from reverse osmosis. Too, even with the reduced energy consumption of the newer plants, it still takes a lot of electricity to force millions of gallons of water through osmotic membranes, and that raises carbon emission concerns.

Sedlak says the intake and brine disposal worries largely have been addressed by the newer systems, but that greenhouse gas emissions seem an ineluctable downside of the technology.

“Australia has used solar and wind farms to produce equivalent carbon offsets for the greenhouse gas emissions produced by their desal plants,” Sedlak says, “but there has been no big move here to dramatically ramp up green energy or otherwise institute carbon offsets for our desalinization initiatives. So that remains an issue.”

Bottom line, concludes Sedlak: Desal is good insurance, but it shouldn’t be the default choice. 

“Desalinization can make sense for coastal areas, and most of California’s population is in coastal cities,” Sedlak says. “So it’s good to know that if all else fails, we have desal. The cities won’t run out of water. But we also have a very good sense of the economic and environmental consequences. We know that many other options cost much less and have fewer environmental impacts, particularly in regard to greenhouse gas emissions. So we should pursue those first.”

Share this article:
Google+ Reddit

Comments

Glen, thank you for highlighting desalination, it is our best solution for meeting current and long-term water needs of California. Considering the increasingly unacceptable consequences of climate changes we are experiencing today, desalination must be our highest priority for protecting quality of life for our newest and all future generations.
The implications that through innovation the energy required to desalinate water will some how be reduced is nonsense. The energy needed to pump water molecules through a membrane that will halt salt molecules is dictated by physics. While we have progressed from the crude and inefficient reverse-osmosis technologies of the past, we have essentially reached the limit and can’t expect further reductions in energy use or the associated greenhouse gas emissions. The suggestion that renewable energy can eliminate this problem is misleading, at least until the grid is beyond 100% clean energy. Presently, any solar or wind energy diverted to powering desalination will have to be replaced with fossil-fuel energy. There is no way around the fact that desalination is already exacerbating the very problems that have brought us this drought. The energy costs of the desalinization process may be about the same as pumping water over the Tehachapis, but that still is only a part of the energy needed and an even smaller part of the overall costs. Water, once over those mountains, flows largely by gravity to its destination. A coastal desalination plant must now have it’s output pumped up to its users. Furthermore, beyond energy, there are the capital and non-energy operation costs of desalination that make the option unaffordable except in a taxpayer-subsidized situation. The vast profits of the companies that build and operate these expensive plants are the reason for their overblown promotion. Given that desalination energy requirements has already reached its theoretical asymptote, shame on Sen. Boxer for seeking millions of federal dollars to research it further. It’s a mature technology and perfectly fine for isolated, emergency applications. Let’s hope science advisor Holdren has more sense and realizes there is no shortage of fresh water on the planet – it’s simply not distributed in the same proportions as the population and industrial/agricultural users. The Romans figured out long ago that water transport is the low-energy solution to quenching the thirsts of people choosing to live in dry locations. Today there are far better solutions than land-based aqueducts. Ocean-based water transport is a far more logical and economical solution than desalination or pumping water over mountain ranges.
People are worried about what to do with the brine? Well, brine can be used for numerous projects. Every winter, snow accumulated in the Sierra Nevadas and other parts of the state, and indeed outside the state, blocking roadways, runways, etc. Well, did you know brine is a viable alternative to road salt? Brine can also be used for controlling dust in more arid climates, the nitrates can be used as a fertilizer, it can be used in health supplements, and in metal recovery, the gypsum and calcium discharged are widely used in the building industry for drywall, plaster, and cement. The magnesium salts are used in the medical industry, selenium is a health supplement and is used in glass making and in electronics, and boron, well boron is used in bleach, pyrotechnics, high-efficiency electronics and current cutting edge solar technology. As for the salt alone, just think of all the applications as Sodium Sulfate, Sodium Chloride, Calcium Sulfate, Calcium Chloride, Magnesium Sulfate, Sodium Carbonate, Calcium Carbonate, Sodium Nitrate, Magnesium Chloride, Calcium Borate, Silica, etc. and then there are the various trace minerals which are also useful. Many of the elements found in the brine can be used in the plant’s own solar systems which can easily create enough heat and electricity to fuel the systems in the plant. Even still, has anyone thought of possibly looking into forward osmosis? How about evaporation, or cryo-desalination?
Why would California divert power when it can be created on sight?
Pumping or otherwise transporting water from desal locations to their destinations takes just as much energy as getting it from the area’s of the planet where “there is no shortage of fresh water.”
We must wake-up to the new fact of life in California that we are losing our quality water supplies, and because leaders in both political parties have looked the other way for far too long, we shall not have enough water for drinking and food supplies very soon, maybe in 2015. Either we build large desalination plants along the coast with the greatest sense of urgency today, or large numbers of people shall have to begin moving out of California. It is no longer relevant that desalination is expensive when failure to have enough water at all is a fact of life.
Anthony, you are right about the urgency, but the solution you suggest is the leading contender only because some influential people are poised to profit wildly from its adoption. Instead of desalination, wouldn’t it be smarter to go with an option that is cheaper, less energy intensive, has little or no environmental impact, and can be tuned to varying water needs?
The question of desalination seems to be a typical knee jerk reaction to a problem that has been around for centuries California is prone to long periods of drought and it is a difficult problem to solve that may cost the citizens of the state more money to live here in this beautiful state. There is no reason other than greed and the flare for dramatics that the state leaders have done nothing to address our need for residential and industrial water just as we lag behind in the development of commercially viable electricity from renewable sources. Get with it California we need sustainable water resources that do not hurt the environment by creating more greenhouse gases or damage the ocean anymore than we already have with our dumping hazardous waste.
Clifford, cheaper and cleaner are always better but not nearly enough to take care of our long-term future needs that are huge in California. We must build large desalination plants along the coast ASAP, and the sooner we start building fusion energy plants the better. We have been far too short sighted in our decisions and water is one thing we cannot afford to fail at any longer now that we have passed 400 ppm CO2. Politicians in both parties have failed us and we must force them to do the right things ASAP. You should read: Can We Adapt in Time? http://alumni.berkeley.edu/california-magazine/september-october-2006-gl...
Anthony, our water and energy problems are linked in many ways. Dependence on fossil-powered desalination is an unnecessary link and should be avoided at all costs. While droughts in California seem cyclic, if you agree that the present one has been exacerbated by a warming due to present CO2 emissions, then energy-intensive water making is clearly counterproductive as long as any of our energy comes from fossil resources. - - - - I’m all for fusion. I’m all for a rapid roll out of renewables. But California’s acute water problems can’t wait, especially since locations of fresh water abundance are simply letting that precious resource flow into the sea to begin again it’s passage through the nature’s cycle. - - - - The average residence time for a water molecule in the ocean is 3,000 years before evaporation when it can once again come back to us in the form of precipitation. Intercepting those fresh-water flows before they mix with ocean water can provide thirsty locations such as California with immediate relief and with no negative impacts back at the source. - - - - The technology exists now to move this water at a fraction of the energy costs and an even smaller fraction of the capital costs compared to desalination. These methods can be implemented quickly and would be delivering water long before our politicians decide who gets rich building or retrofitting a desalination plant. Oh, I appreciate the link to the article. While I do not see the failure of Gloucester’s groundfish fleet being at all analogous to our present climate crisis, most of the author’s other points are valid.
Clifford, I would like to think you are right, but climate changes are causing unacceptable and increasingly out of control consequences today, and time is running out faster than we are making the right things happen. So a paramount question is, what solutions do we have available that we can implement immediately to save our state and planet?
That’s precisely my point, Anthony.
Desalination seems quite impractical for quenching the thirst of California’s primary water user: the corporate industrial farming sector. We need to stop framing the draught conversation in terms of slaking Californian’s thirst or in terms of getting Californians to understand the value of water. There is plenty of water flowing through the current infrastructure to supply the personal needs of Californians. But the massive feed lots of industrial meat and dairy, and the heavily irrigated fields of monoculture crops (many of which support that same meat industry) make the California ecosystem into a crisis zone that they label “drought.” The so-called drought would be a non-issue if these destructive and unsustainable industries dried up and blew away. Cries of doom for the economy notwithstanding, we must deal with the real problem here, for which water scarcity is only a symptom. Corporate industrial agriculture – especially feedlot meat and diary, and water-intensive crops like almonds – have no place in California. Desalination is a red herring that shifts the debate into the realm of personal use and thirst, evading the core issue of unsustainable water use by corporate industrial agriculture.
Its not a secret that desalination technology has been used for decades by both naval vessels merchant marine and the cruse liner industry…this technology that turns sea water into fresh drinkable water isn’t new. USN retired
Indeed. The technology is real. But California’s industrial agriculture requires entire rivers of cheap water. The energy cost for desalination seems prohibitive – both in dollars and in terms of massive externalities spawned by energy production required to achieve it at that scale. Even if the comparatively minuscule onboard desalination systems used on ships could be scaled up to the levels required to supply California’s wasteful industrial meat and dairy producers and millions of residential and commercial users, we would likely have much to learn about the impacts of that scale of desalination – impacts beyond the huge amount of energy and investment that it would require. Technological fixes inevitably rely upon an array of hidden externalities. It’s becoming increasingly obvious that these externalities often outweigh the benefits. So we should be skeptical about desalination as a solution to the drought, and should learn more about the downsides in terms of environmental impacts, projected lifespan of the infrastructure, and real costs. It would seem more hopeful to take this drought as an opportunity to completely eliminate industrial agriculture here (especially industrial meat and dairy), with all of its toxic, climate altering, community killing effects. No amount of technology can assuage the insatiable needs of the parasitic capitalism that infects our farming sector and culture at large.
And move it to where, Kent. Where is there the right combination of climate, water, land, and workers to replace what’s currently being done in California. Isn’t it better to improve the present system rather then walking away? Simply charge the prices we pay in the rest of the US and the system will fix itself.
Reread my original post, Clifford. I already answered your question. It is not better to “improve the present system” because that system needs to go. When I say that corporate industrial feedlot agriculture needs to dry up and go away, I mean that it needs to cease. Relocating it would of course be absurd. Study after study has debunked the myth that we need corporate industrial agriculture to feed the world. The only thing that this toxic system feeds efficiently is corporate profits. As the drought strangles this parasitic system, we should take the opportunity to replace it with extensive proliferation of sustainable, small scale, local, organic agriculture that not only uses less water, but sequesters carbon and provides healthier food. The vast industrial wasteland of Central California should revert to whatever it reverts to without water. The toxic, diseased, obese couch potatoes across America can wake up and realize how unsustainable their diet of cheap processed meat and dairy has been. They can either die of starvation or eat a healthy organic diet of food grown in their local region. Here in California, we’ll do just fine without the parasitic juggernaut of corporate industrial agriculture that demands half of our entire water supply, competes with transport for the top spot in carbon emissions, and spreads sickness and extinction. We should be extremely skeptical of desalination schemes because: 1. Alternatives abound, 2. It’s expensive, 3. It would exacerbate global warming – directly through energy consumption and indirectly by propping up a CO2-spewing system, 4. It invites increased corporate control and abuse, 5. Fisheries and marine environments will be further compromised, 7. It promotes environmental and social Injustice, as detailed here https://www.foodandwaterwatch.org/factsheet/seawater-desalination-soluti... and many other sources. Letting private corporations build huge energy gobbling facilities along already compromised coastlines to suck up vast quantities of already compromised coastal waters to feed sick and inefficient, obsolete corporate industrial farming models wreaks of the same technology-obsessed free market dogma that is already threatening human survival.
I spent a week in Dubai recently. They have an ocean on one side and a desert on the other. I could shower as much as I liked and out of the window I could see a green golf course. Tiger Woods was playing on it while I was there. Some 500 new hotels were planned. I was there for an engineering convention which included an inspection of their saltwater conversion plant. - So, California, what is the problem?

Add new comment