Perhaps you’ve heard that the Southern Nevada Water Authority wants to build a 300-mile pipeline to pump ground water from Northern Nevada to Las Vegas. The SNWA says it’s vital that we have another source of water because relying almost exclusively on the Colorado River via Lake Mead is risky and bad for business, so the agency is in Carson City right now asking the state engineer for permission to take 126,000 acre-feet of water annually out of the ground from rural Nevada valleys and send it to Southern Nevada.
Perhaps you’ve also heard that a lot of people think that’s a bad idea. They say it’s too expensive—cost estimates range from a low of $3.5 billion to a high of $15 billion, including interest on bonds to fund the project—that it will deplete ground water that took centuries to accumulate, harm ranchers who depend on the water for a living, destroy native vegetation and endanger native species.
It’s a classic conflict: development versus preservation, rural versus urban, north versus south. To listen to SNWA General Manager Pat Mulroy talk, either we build the pipeline or Las Vegas is doomed. “What people don’t understand is that there are no other options,” Mulroy said on KNPR’s State of Nevada on Sept. 29. “I mean if there was any other option that we could pursue that would work during drought conditions on the Colorado River, we’d be pursuing it.”
The thing is, there are other options; some plausible and eminently sensible, and others a bit far-fetched. This pipeline proposal is so controversial, so bitterly opposed by the people on the other end of the spigot, that we should be exploring every alternative. Here are a few of them:
The easiest and cheapest way to have more water is to use less of it. And Southern Nevadans use a lot of water. As of 2008, we were going through 250 gallons daily per capita. Nationwide, the per capita number is closer to 160 gallons. It’s not really fair to compare a city in the driest desert in North America with places where water falls from the sky more than occasionally, so rates in other hot, dry cities are more illustrative of our relatively lavish water use. Phoenix, for example. Its citizens consumed 174 gallons per capita per day in 2008. In Tucson, the number was 182. It’s true that both Arizona cities get more rain than Las Vegas, but it’s also true that both have long-standing conservation cultures we lack. Phoenix residents are urged to do laundry at night, flush their toilets only when necessary and install xeriscaping. Tucson is implementing building codes that will require new housing to capture and reuse gray water.
The good news is we aren’t nearly as wasteful as we were in 1990, when we each used 350 gallons per person daily. Our reduction is, in large part, thanks to SNWA-backed conservation measures like paying people to replace their grass and mandatory watering restrictions. And they aren’t done yet. By 2035, they’d like to see us using 199 gallons per day. It’s a noble goal, but still higher than present-day usage in many Southwestern cities. SNWA conservation manager Doug Bennett says that’s because we’re drier than those cities. “You really can’t compare one city to another,” Bennett says. “The hotter and drier it is, the same activity will require more water to get the job done.”
Nonetheless, there is an obvious and direct correlation between saving water and needing less of it. The SNWA’s own Water Resource Plan, published in 2009, states that achieving its 2035 conservation goal will save 276,000 acre-feet of water annually, more than double the maximum amount it wants to bring here in the pipeline.
Get the salt out
No, we don’t live near the ocean. Yes, pumping desalinated water to Las Vegas from the ocean—uphill—is a bad idea. So why do people keep talking about removing salt from seawater as a way for landlocked Las Vegas to quench its thirst? Because it does make sense for areas closer to the coast that also depend on the Colorado River. If California or Mexico could desalinate to help meet their needs, desalination proponents believe, they’d put less of a demand on the river, meaning we could rely on it more. Opponents brush off the idea as politically untenable and technologically unfeasible.
A short history lesson: 89 years ago, seven Southwestern states came to an agreement on how to divide the Colorado River. Because Nevada had little agriculture and few citizens, it got the smallest share of the water. California got the most. That still holds true today.
Desalination has been around for a long time—Aristotle thought a series of filters would work—but until recently it has been too energy intensive to be economical. The older method of boiling seawater to capture fresh water steam only makes sense in places like the Middle East where fresh water is scarce but oil is plentiful. Reverse osmosis, which is forcing seawater through filtering membranes at high pressure, is more economical but still energy intensive.
With existing technology, desalination is too expensive, says Heather Cooley, co-director of the water program at the Pacific Institute, a California think tank that studies environmental issues.
“It can be several times more expensive [than conventional methods of providing fresh water], up to $3,000 per acre-foot,” Cooley says. (An acre-foot is roughly equal to enough water for a family of four for one year.)
But technology may save the day for desal. Filtering seawater through carbon nanotubes shows promise and could reduce the cost of desalinated water by 75 percent compared with reverse osmosis. But even at current costs, desalination is a component in contemporary water planning. San Diego County is building a 50-million-gallon per day plant. Meanwhile, a 25-million-gallon-capacity plant began production in Tampa, Fla., in 2008. The San Diego plant will be the largest such facility in North America. It will produce 56,000 acre-feet per year, less than half of the amount SNWA wants to take from Northern Nevada. However, at $320 million, it is about one-tenth the price tag of the lowest estimate for the pipeline.
Desal can also be green, as a plant that went on line in Perth, Australia, in 2006 proved. The $371 million facility has a 66-million-gallon capacity and is powered by renewable energy from a nearby wind farm.
In 2009, an investigator from the Lawrence Livermore National Laboratory published a paper called The National Smart Water Grid, which suggested that pumping excess floodwater from the Mississippi, Arkansas and Missouri rivers into the Colorado River and ultimately Lake Mead is not as far-fetched as it sounds. The 1,100-mile system of pipes and canals would alleviate seasonal flooding in the Midwest and add an additional 10-million to 60-million acre-feet of water to the Colorado for use throughout the system. It would cost $82 billion to build, according to the 2009 estimate, making it a project on the order of a modern Hoover Dam, Tennessee Valley Authority or interstate highway system. Big-picture stuff.
“Where will the money for infrastructure construction and operations come from?” study author Ronald Beaulieu writes. “Sale of captured fresh water! The value of 60 [million acre-feet] of fresh water is estimated between $30 billion and $140 billion and could be realized from the capture of water from a single major flood. Floods are anticipated to repeat frequently. Even minor floods will provide the opportunity to capture large volumes of fresh water.”
The SNWA itself has aired the idea of moving water from the Midwest into the Colorado River, in a misty-future sense. And given the political wrangling and infrastructure costs it would take to get it built, the future is where this idea will likely stay for a long time.
Water is heavy—a little more than 8 pounds per gallon—so moving it from one place to another has always been a problem. Trucks can’t carry enough of it to make it worthwhile, while ocean-going tankers burn a lot of fuel.
California inventor Terry Spragg believes he has an answer: the Spragg Bag. The idea is simple: Fill an enormous plastic bag with 4.5 million gallons of freshwater from a source that has a lot of it and tow it in the ocean behind a barge to a place that doesn’t. The bags can be linked up in a long ocean-going train towed behind a single barge. Freshwater is lighter than saltwater, so the bags float; videos from a test run of two Spragg Bags linked together show people walking on the squishy things that rise only a foot or two out of the water.
As is the case with desalination, the bags would be used to help California meet its water needs, leaving more of the Colorado River for those of us upstream. Spragg envisions trains of up to 50 230-foot long bags being towed from Washington State to Southern California via the Pacific Ocean by a single tug boat.
The idea may be wacky, but it’s not unprecedented. In 2001, a company called Nordic Water Supply moved water in 600-foot bags from Turkey to Cyprus. They stopped because it wasn’t profitable.
Spragg says his bags are proven, but acknowledges that they aren’t in use anywhere in the world just yet. His website is touting the potential sponsorship benefits of having a corporate logo bobbing around on huge water balloons in the ocean as one way to address the costs.
Maybe he’s ahead of his time.