GEORGE F. WILL Las Vegas betting on its water diviner

LAS VEGAS -- In this city of histrionic architecture, the building that matters most may be the bland, low-slung headquarters of the Southern Nevada Water Authority. The general manager since the authority was formed in 1991, the elegant, no-nonsense Pat Mulroy, 52, is determined to prevent a water shortage from inhibiting the growth of this city that is dedicated to the proposition that inhibitions are sinful.
She is dealing with a five-year drought, the worst in 100 years of record keeping, and perhaps -- tree rings suggest this -- the worst in 500 years. She also is dealing with reverberations from the day in 1877 when Thomas Blythe strode into the Colorado River near the California town now named for him, 100 miles south of the Nevada border, and claimed for California 9 million acre-feet of the river -- an acre-foot being about 326,000 gallons.
Because of the principle "first in time, first in right," California got an abundance. Then, in 1922, six other states -- Colorado, Wyoming, Utah, Nevada, Arizona, New Mexico -- joined with California in the Colorado River Compact. Westerners say whisky is for drinking and water is for fighting over, but the seven states can do pretty much anything they can agree to, such as "banking" water underground to use in trading river entitlements. They cooperate to keep Washington from butting in.
Lake Mead
Today California gets 4.4 million acre-feet. Las Vegas' water needs are supplied mostly from Lake Mead -- down to 59 percent of capacity -- and, upstream from Mead, Lake Powell, now at 34 percent of capacity, its lowest since it started filling three decades ago.
When Mormon settlers arrived here in 1855 the town was called Las Vegas Springs -- an oasis refreshing travelers from Salt Lake City to another community taking root in an arid place, Los Angeles. Today, 30 million people from Denver to Salt Lake City, Phoenix, Tucson, Los Angeles and San Diego -- almost a tenth of all Americans -- depend on the river's water. But agriculture sops up 90 percent of it. The sprawl of Phoenix onto agricultural land actually decreases water use.
The Strip -- the portion of Las Vegas Boulevard that has 15 of the world's 20 largest hotels -- features vast fountains, a sea battle between pirate ships and an 8.5-acre lake in front of the Bellagio hotel. However, Mulroy says, The Strip accounts for less than 1 percent of the state's water use -- while producing 60 percent of the state's economy. The average hotel room uses 300 gallons of water a day, but it is all recycled. The drought has elicited un-Western demands to slow this city's growth, but Mulroy briskly demurs: "You don't use a growth moratorium to manage through a drought." You use, primarily, the market.
For example, most people who move here -- there were a record 29,248 new home sales in 2004, an increase of 16 percent over 2003, which also set a record -- come from less arid places and they use home irrigation systems to reproduce the green lawns they left behind. Retirees, especially -- roughly 20 percent of the metropolitan area's 1.6 million residents are 55 or older -- come for the abundance of sunshine and the absence of an income tax. They demand grass.
"It is," says Mulroy, "mind-boggling: they move to the desert and plant Kentucky blue grass" -- a particularly thirsty kind. "We were," she says incredulously, "putting grass on medians." It was, she says, "like moving to Alaska and walking down the street in a bathing suit in January."
Desert plants
The city got little response paying 40 cents a square foot for removed grass. But Nevadans understand pricing: $1 a square foot has bought the removal of turf to 50.9 million square feet, for annual savings of 2.8 billion gallons of water. Now garden stores stock desert plants for "water smart landscaping."
Americans, passionate subduers of nature, are surpassing themselves here. Having built the nation's fastest growing city in a desert, they are now bringing the desert back to town. From 2002 to 2003, while population was growing 5,000 a month, water consumption declined from 318,000 acre-feet to less than 272,000, and was even less in 2004.
Today Mulroy is worrying about snow. Falling in the Rockies, it should melt and flow into Lake Powell. But when mountain winds pick up, "sublimated" snow evaporates. The moisture goes into clouds "and rains on Nebraska" -- an indignity. Mulroy is not amused. If she decides to stop it, this betting town would not bet against her.
Washington Post Writers Group