Posted on 03/22/2008 10:27:04 PM PDT by grundle
Desalination gets a serious look
It isnt cheap and it requires lots of energy, but fresh water from the ocean might be part of Southern Nevadas future as other sources dry up
By Phoebe Sweet
Fri, Mar 21, 2008
As the West dries up, water managers, politicians and environmental groups alike are searching for an option any option to create water.
Recently, desalination has been the popular answer. Even the Southern Nevada Water Authority, which has said the technology is no silver bullet, is considering desalting despite its many challenges.
Last month, Gov. Jim Gibbons made waves when he said he would rather see Las Vegas rely on desalination plants on the Pacific coast than on the controversial planned pipeline to move rural Nevada water to Las Vegas.
Southern Nevada Water Authority General Manager Pat Mulroy has not talked with the governor since he made those comments in Fallon on Feb. 21, but last week she said Gibbons just doesnt understand how complex it would be to build a desalting plant on the coast of California or Mexico and trade the water it produces for more water from the Colorado River.
I know that the governor is a rancher himself, and he would probably love to have an alternative for the in-state (pipeline) project, Mulroy said. I would love to have an alternative to the in-state project.
Desalination is sure to be part of the valleys future water supply, she said, but there are environmental and political challenges to using the technology, which is expensive and uses lots of electricity.
And in the end, Mulroy said, a desalting plant would be useless if drought continues to diminish the Rocky Mountain snowpack that feeds the Colorado Rivers flow into Lake Mead, the source of 90 percent of the Las Vegas Valleys drinking water.
If the lake continues to shrink and shortage guidelines enacted by the seven Colorado River Compact states kick in, Las Vegas would no longer be able to use traded or stored river water.
When shortages get declared those become impossible to take, Mulroy said. All those opportunities either disappear completely or become severely limited in times of shortage. The only thing we can rely on in times of shortage are things that begin in Nevada.
Thats one reason Mulroy says developing a pipeline or some other native Nevada water source is so important.
Additional resources were trying to develop to protect against a drought would also disappear if we take them as Colorado River water, she said. Theyre not useful at the time we need that reliability most.
Another major consideration is the states relationship with the six other states, Mulroy said. Because those states were told Nevada was committed to the pipeline project, Las Vegas has been promised the first 75,000 acre-feet of any new Colorado River water augmentation project, such the Drop 2 Reservoir planned for Southern California adjacent to the All-American Canal. An acre-foot of water is enough to supply about two single-family homes for a year. In return, the state must develop an in-state water resource.
If Nevada were to not develop in-state, its credibility would be so badly tarnished, Mulroy said. We (would be) saying, We will not do what all the other states have done. It would be viewed very much as a breach of good faith, on Nevadas part, to rely completely on other states resources, particularly during shortage.
Despite the need to develop water resources that dont rely on the overstretched Colorado River, the Water Authority is seriously considering desalination in general and an existing desalting plant in Arizona in particular as options, officials said.
Desalination is part of a 2006-07 study of options to augment Colorado River flows commissioned by the seven states. The results of that study are expected to be released within weeks, according to the authority. The study also examined other augmentation options such as cloud seeding and vegetation management.
The study was the first time the authority formally studied desalting, although a spokesman said the option has been discussed informally since 2000.
For now, the authoritys official position on desalting remains that the technology is not promising as a near- or middle-term option in the face of the drought on the Colorado River ... because it does not reduce our 90 percent reliance on the Colorado River. It has been viewed as more of a longer-term option, spokesman Scott Huntley said in an e-mail last week.
Mulroy said desalting ocean water could play a role in plans to pump from the eastern Nevada aquifer, the source for the pipeline project. During years when shortage guidelines arent in effect, Nevada could rely on desalted water instead of rural ground water to augment its supply.
That would give us the freedom not to pump in areas of the ground water project if were looking to let an area rest for a while, she said.
The authority in December also began considering use of a plant in Yuma, Ariz., that removes salt from brackish ground water. The plant was built by the Bureau of Reclamation in 1992 to improve the quality of water flowing into Mexico as part of a treaty agreement, but has been mothballed since then because it wasnt needed.
Although it is too early to determine whether water would be available for Nevada or what the price tag would be, Huntley said that the initial concept includes an exchange of Colorado River water with Arizona.
The authority is analyzing the engineering, cost, and environmental and legal barriers to the plan.
The plant could produce 100 million gallons a day, enough water, on average, for about 224,200 single-family households. The plant uses 20 megawatts of electricity when operating at full capacity. It was tested successfully, although not at full power, from March 1 to May 31 last year.
The cost of the plant was equivalent to $250 million today, according to Jim Cherry, Yuma area manager for the Bureau of Reclamation.
During the wetter years when it was being built, the plant was criticized as a waste of money. As the level of water in Lake Mead has changed, so have opinions about the plant.
Cherry said the Yuma plant has served as a technological example for new, successful desalination plants being used around the globe. There are about 13,000 desalting plants operating globally, including 123 in Florida alone, he said.
Advocates agree with Gibbons that its time Nevada reconsidered desalination.
The governor is pursuing 21st-century technology as opposed to the 19th-century pipeline technique, said Mark Bird, a professor at the College of Southern Nevada and a desalting proponent. He believes a desalination plant in Mexico would be a less expensive option than a pipeline from eastern Nevada.
Mulroy said a Mexican plant is more feasible than one in California, where land prices are high and a strong Coastal Commission has opposed other desalting plants.
Late last year the Coastal Commission approved the $300 million Poseidon Resources desalination plant planned for Carlsbad, Calif., to provide San Diego with drinking water. Environmental groups have rallied against the plant, which has been in the works since before 2000. Opponents complain the plant will be an eyesore and say brine released back into the ocean will kill fish.
Mulroy said it would be even harder to get a plant approved in California if it were intended to ease Nevadas water crunch.
And no matter the location, cost will be an obstacle.
Desalting is expensive and energy-intensive, according to Peter Gleick, president of the Pacific Institute, an environmental research group based in Oakland, Calif. The institute released a study on desalting in June 2006 that detailed its potential but also the hurdles to widespread use of the technology.
Conservation and efficiency are cheaper at the moment, Gleick said. To build a desalination plant and use the water locally costs about $1,000 per acre-foot, he said, or $3.06 for 1,000 gallons.
Take, for example, the desalting plant recently built in Perth, Australia. It cost $357 million. It will desalt more than 26 million gallons of water a day, enough, on average, to serve about 58,300 homes. It also will use 23 megawatts of electricity produced from wind, as much as used by 17,250 average single-family homes.
But the Perth plant like Yumas and the many others like it across the United States and around the rest of the world also proves that desalination is a feasible option, proponents say.
This is a country that put a man on the moon, a country with enormous intelligence and financial resources, said Launce Rake, a pipeline opponent and spokesman for the Progressive Leadership Alliance of Nevada. We can do this if we have the political will.
Lots of water in the upper Midwest. Bring your snowsuit, snow shovel and carrots for the snowman’s nose. No ice needed for your daily bottle of bourbon on the rocks.
The water will get saltier and saltier as it evaporates and they take out fresh water. They would need a return flow to keep the salt constant.
Repeat after me: As long as the oceans are full, there is NO such thing as a shortage of water, there is ONLY a shortage of the will to spend the money necessary to spend the money necessary to deliver water of sufficient quality and quantity.
New Mexico has completed a pipeline from the Colorado to the Chama/Rio Grande that utilizes pumps to a higher elevation and a pipeline dug thru the divide, but I don't know what the initial elevation of the water is or what elevation of the thru-mountain pipeline is.
And have Mexico in a position to threaten to stop water supplies to part of the U.S.? Not a good plan.
Nevada would build a de-sal plant in/for Mexico's use and Mexico would relinquish their rights to an equivalent amount of Colorado River water to Nevada.
I can hear the environmentalists predicting that Nevada will turn the oceans into salty "dead seas", use up all the water, and ultimately turn the whole earth into a desert. They made similar claims when a desalinization plant was proposed in Australia.
So, “Hot-N-Salty” water is preferable to merely salty water?
;-)
Nevada has so much underground water, desalinization should not even be an issue. And Gov. Gibbons should know it.
Nye county alone has enough water to take care of the Four Corners states for 500 years.
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I can hear the environmentalists predicting that Nevada will turn the oceans into salty “dead seas”, use up all the water, and ultimately turn the whole earth into a desert. They made similar claims when a desalinization plant was proposed in Australia.
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Yet more proof that liberalism is a mental disorder. Little thought is given to where water goes and how the hydrology cycle works.
As long as the user of the RO product does not sequester the water, it will eventually return to the ocean, either by runoff or through evaporation. It is bad enough that anyone doesn’t care to understand this. It seems that some people actually prefer the lies when they could learn from the truth.
DSRO means Deep Sea Reverse Osmosis. At 1800 feet below the surface you get the natural 900 psi to run an RO film-unit, 1 gal/hr/2 sf with spiral wound film-tech RO films. Then a submersible pump and lines to shore. This would be ideal if you had a 1800 deep trench just off shore(like Monteray CA). The only power required is for the submersible pump, plus staging pumps from seafloor unit to shore. But no brine disposal problems, no on-shore pressurization units, only occaional back flushing to kick back drifting debris in the water. There would be a barge on the surface to raise/lower the unit for servicing, with a JASON underwater unit to disconnect/reconnect lines.
This concept is explained in an article in infinite-energy magazine.com about 6 years ago, the “water” issue, by Andrews and Bullock.
I agree with you. People who say there's not enough water don't make any sense.
---------- The water will get saltier and saltier as it evaporates and they take out fresh water. They would need a return flow to keep the salt constant.
But that would take centuries -- and meanwhile, the inflow would generate lots of electricity -- and it would make Las Vegas a seaport city. Before it gets too salty the Snake River could be diverted from Twin Falls (elev 3745 ft) into Nevada -- there's more electricity.
How long it took the lake to get salty would depend on the inflow rate & size of the lake.
Besides, the greens would never let you flood Death Valley, even if it would save thousands of human lives - you might kill some horned toads or such.
” Opponents complain the plant will be an eyesore
As much an eyesore as thousands of people with NO water????????????????????????????
THAT IS SO TRUE! Isn’t earth 75% water surface?
Interesting idea. But I'm sure there's some rare little Death Valley desert dweller critter, that would get eradicated in such a plan, and that will get the enviro's panties in a wad.
Shhhh! We're trying to stage a disaster over here! Federal dollars are at stake! ;)
I see but you have missed the obvious "flaw" in such a plan. Notice the unforgivable "lack of need" for carbon credits in such.
So back to the drawing board with your horrendously flawed system, you environmental heretic you!
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