Las Vegas CityLife: PLAN's Launce Rake says the science is showing that the proposed pumping of rural groundwater to support urban growth is a dangerous idea.  

by ANDREW KIRALY

Forget labcoats and clipboards and computers. Back in the day, a hydrologist's best tools were a sturdy pickup truck and a good eye for plants. That's what scientists of the United States Geological Survey put to use when teams of them crawled over Nevada in the 1960s and logged an inventory of the water underground.

"They drove around in pickup trucks and mapped out the extent of plants that use groundwater," says Jim Thomas, a research professor with the Desert Research Institute.

See where the greasewood shrubs grow thick along a line in a geographic bowl? There's water below. How much? Oh, about a tenth of an acre-foot. Give or take.

Photo Illustration by Bill Hughes

"They spent a couple months in a given basin using a standard approach, but they didn't have a lot of data to go by," says Andrew Burns of the Southern Nevada Water Authority. "In terms of an estimate, it's pretty decent, and since that time a lot of additional data has been collected."

The statewide "reconnaissance" survey from the '60s was a piece of thumbnail-sketch science that went broad, but not very deep. But the results are nothing to sniff at; heck, they're what the state engineer uses as a guide when deciding how to dole out groundwater rights. The comprehensive water portrait shows that Nevada has more than 230 groundwater basins. Now, more than 40 years later -- in a rapidly growing state where water is gold -- scientists still refer to that dated snapshot of our groundwater situation. There hasn't been a statewide inventory of water since the '60s. Since then, a patchwork of studies have offered updates here and there, but the overall picture isn't as clear as you'd think.

"The interesting thing is that, obviously, some of that data is old," says Allen Biaggi, director of Nevada's Department of Conservation and Natural Resources. "And there are some new methods of evaluating basins."

To date, 81 basins in Nevada have had their water picture updated since the original reconnaissance reports, helped along with newfangled tech like satellite imaging, aerial photography, "prism maps" and special domes for measuring how plants discharge moisture.

"[Measuring groundwater] is a scientific method and process, but there's a bit of art to it as well," says Biaggi. "When you look at the track record that [State Engineer Tracy] Taylor's office has had, we've got a pretty good handle on water resources."

But while the science has advanced and our understanding of groundwater has evolved -- sure, it's underground, but doesn't so much sit in pools so much as spread across vast, peach-pit crags of carbonate rock -- exactly how much groundwater Nevada has is still shrouded in a bit of mystery.

And with the state facing some looming environmental issues -- global warming, an extended Southwest drought that seems to be the rule rather than the exception, and the Southern Nevada Water Authority poking around in rural backyards for water to sate a thirsty Las Vegas -- well, you'd think we'd have a better grasp of how much water is down there. Not quite.

"We've got all kind of stressors on the resource, so it's important we have good data," says Biaggi.

IS OLD DATA BAD DATA?

Don't panic. The Bellagio Fountain isn't going to start spewing dust as tourists flee, screaming in terror. But water wonks don't all see eye to eye on how solid the data from the '60s are.

"The old studies were pretty darn good," says Biaggi. "While they may be old, they're still pretty good in terms of information for making water decisions."

Others are a bit more tempered in their enthusiasm.

"For the level of effort and time they had, they did a pretty good job [in the '60s]," says Thomas of DRI. But "pretty good" doesn't always cut it in scientific circles. In some basins, "I would guess we could be off by plus or minus at least a 100 percent. Some will be right on, some will be way off. I don't think that's unrealistic. I wouldn't be surprised. Right now, almost everything is based on the original reconnaissance estimates. It's a good starting point. But [updating the water assessment] is very pressing."

So why aren't we starting over? Because when it comes to state funding, water studies get left high and dry.

NEW METHODS, BUT LITTLE MONEY

A third of the state's 236 basins have been re-estimated in a sort of crazy-quilt of studies taken on by everyone from federal scientists to university researchers to private consultants.

Why hasn't there been a comprehensive update? For one, finding water isn't cheap. "To really nail down a basin -- it takes a half a million to a million to detail a basin to get the kind of data you need to collect," says Thomas.

And recent legislative sessions haven't exactly unleashed a flood of money on water wonks. For instance, in 2005, the state gave DRI $1 million for equipment to study groundwater -- but no money to actually conduct the study. (It's not like the equipment has been sitting around gathering dust -- but it sure would be nice to pay some scientists to get out into the field, says Thomas.) Then, $2 million state officials requested for water research in 2007 didn't make it through the session. However, in a state facing a budget shortfall in an economy flirting with recession, a hundred million or so for inventorying the state's groundwater is hardly chump change. (Perhaps ironically, it was Gov. Jim Gibbons who asked for the $2 million for water research in 2007).

"Unfortunately the Legislature had to make some tough decisions, and that was one of the things that didn't get approved," says Biaggi. They plan to go back in 2009 to ask again.

SLIPPERY SCIENCE

While water officials and scientists offer reassurances that there's plenty of water out there in Nevada -- in fact, many studies have found there's more than previously thought -- the most recent research has shed further light on a new conception of groundwater. It's decidedly different than the popular idea of groundwater as big bathtubs of liquid, static and placid, just waiting for someone to dip in.

Even when the money's there to plumb the desert depths for water, the science isn't always crystal clear. A case in point resides to the north, where from 2005 to 2006, federal scientists were dispatched to study the area where the Southern Nevada Water Authority wants to tap rural groundwater. The $6 million study scrutinized 13 basins straddling the Nevada-Utah border. The Basin Area Regional Carbonate Aquifer System Study (aka BARCASS), paid for by an amendment to the Southern Nevada Public Lands Management Act, was seen by critics of the rural pipeline plan as a scientific sop to skeptics and a Pass-Go card for the water authority -- There, there, now. There's plenty of water in the area, see?

The good news is there seems to "extra" water flowing out of the 13-basin study area. But the study also had the perhaps ironic effect of reinforcing another idea that's quickly gaining traction -- and one that might make water authority officials squirm. The emerging idea is that groundwater, scientists are finding, isn't merely confined to a basin as though it were sitting in a sink. Rather, the water slips and slides around beneath the earth in larger patterns called regional flow systems. The inconvenient result: Pumping water at Basin A could spell trouble for Basin Z -- or, say, the endangered species of fish that call Basin Z home. Indeed, some critics think BARCASS raised more questions than it answered.

"These aquifers are all connected, and they're the source for surface water, including rivers that feed Lake Mead, and springs and seeps that are critical habitat for rare plants and animals," says Launce Rake of the Progressive Leadership Alliance of Nevada, a foe of the rural pipeline plan. "We don't understand what's happening out there. Some scientists are getting a grasp, and the more we know, the more fragile those interconnected environments look."

Even scientists who worked on the study tend to concur.

"One of the big question marks is if you start to pump, are there going to be impacts around the Great Basin into lowering water levels?" says Dan Bright, assistant state director for the USGS's Nevada Water Science Center; he's also an editor on the BARCASS study. "If that's a concern, we need to do little bit more looking at groundwater flow from basin to another. You can't put a well in a basin and say we're just going to look at [the effects on] the basin. We have to look on a regional scale, not just a basin-to-basin scale. There's concern that if you pump from one basin, you may impact another basin. There's concern about how much to pump because the system has never been stressed before, and we don't know how the aquifers will react if you pump it."

As the scientific tools for finding water underground become sharper, it seems the knife can cut both ways.

"I would love to be convinced on the merits of the science that we can go in there and double or quadruple the size of Las Vegas on the back of rural water," says Rake. "If we could do that without threatening the environment and the rural economy, I'd be jumping on board. Unfortunately, there is no free lunch. The more we know, the worse it looks." 

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