New Solutions for the Reality of Drought

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Sept. 20, 2006 — Like death and taxes, droughts in the United States are a certainty, so why not plan for them? That’s what researchers are arguing at a special drought conference this week in Longmont, Colo.

Among the ways unexpected stretches of dry weather can be survived are to develop a national drought policy, as well as learn to store water underground — where it won’t evaporate as it can in a reservoir.

Such a policy would be a entirely new paradigm for the United States, where droughts are currently handled as emergencies and dealt with after they have struck. It was the same in Australia before they instituted a national drought policy in 1989.

"Australia went through the paradigm shift in the late 1980s," said political scientist and drought policy researcher Linda Botterill of Australian National University in Canberra. "Drought was no longer considered a disaster."

The idea, she explained, is to manage droughts like any other risk — in other words, expect them to happen and minimize any related losses.

Australia’s drought policy was a logical step for a nation with one of the most variable climates in the world, said Botterill. It’s also a good fit for the United States — which almost always has a significant drought under way somewhere, every year.

In fact, the United States can probably learn a thing or two from the Australian experience, said climatologist and drought policy specialist Donald Wilhite of the National Drought Mitigation Center at the University of Nebraska in Lincoln.

Wilhite and his colleagues have already made droughts less surprising by creating the U.S. Drought Monitor Web site. The Web site allows everyone to keep an eye on the climate conditions and see a drought as it develops.

Still, seeing a drought coming is of little use if there is no plan to deal with it, or if there's an inadequate water supply. For the latter, some towns and counties may have to drastically rethink their water storage techniques, said hydrology professor Tom Brikowski of the Univerity of Texas at Dallas.

Brikowski reported that he and his colleague Wayland Anderson, a Denver engineer, have studied city water supplies for Hays, Kan., Guymon Okla., and Las Vegas, N.M., and found that the water lost to evaporation on their reservoirs was so extreme that it can sometimes create water supply emergencies with the slightest drought.

By modeling the aquifer that the City of Hays tapped for most of its water, for instance, Brikowski and Anderson were able to show that the aquifer was better off if water was allowed to follow its natural course down the Smokey Hill River, rather than be locked up in the Cedar Bluff reservoir, 20 miles upstream.

The reason this works, said Brikowski, is that the Cedar Bluff reservoir has been receiving far less water than it was designed for and now loses about 75 percent of that to evaporation.

"You get to the point where you can’t afford to lose that much and your only other alternative is to store it underground," said Brikowski. By letting water flow downstream, it percolates into the aquifer, where it is not subject to evaporation and can be pumped up from wells.

Similar underground solutions may be needed in Oklahoma’s Optima Reservoir, which now loses 100 percent of its water to evaporation and Storrie Lake in New Mexico, which was so dry last spring that Las Vegas, N.M., was only 100 days away from evacuations, Brikowski said. Only the summer monsoons saved Las Vegas, he said.

Storing water underground may help in other places as well, where global warming is causing winter snow pack to shrink and melt earlier in the year, said Brikowski. Many parts of California, for instance, which depend entirely on snowmelt from the Sierra Nevada, may need to search for gravely, sandy "alluvial" soils in which they can store more water for the dry summers.

"More efficient storage, perhaps in alluvial aquifers, represents the only real hope for a solution," Brikowski said.