Reid's father eked out a living scavenging ore that the big mining companies had overlooked, until he eventually committed suicide after severe bouts of drinking and depression. The family's misfortunes had begun with Reid's grandfather, John Reid. In 1910, the young homesteader discovered freshwater, which he hoped to tap for farming, on one of his mining claims near Searchlight. But a rival rancher wrested control of the desert spring through an offer John Reid didn't like but "could not refuse." Without water, the Reid homestead withered and died.

Reid has balanced his obsession with growth—and water's incontestable role in that growth—with important environmental initiatives over the years, says Jeff van Ee, a retired Environmental Protection Agency scientist who has worked on Nevada environmental issues since 1972. The senator was one of the first Las Vegas politicians to seek environmentalists' support, Van Ee says. Reid was instrumental in trying to save lakes Walker and Pyramid and the Truckee River, enraging farmers and ranchers in the eastern Sierra. He has led the fight against dumping nuclear waste in Nevada's Yucca Mountain and advocated making the state a hotbed of solar power. Last fall, he angered some rural Nevadans by opposing plans for three new coal-fired power plants in the eastern part of the state because of their greenhouse-gas emissions. At the same time, Reid has become the unchallenged master of the environmental dealmaking that has enabled Las Vegas sprawl. The pipeline deal is the prime example. "If Harry Reid weren't in office, I think the situation would be bleaker," says Van Ee, who once worked in Reid's Washington office. "There's a feeling in Southern Nevada—and Harry Reid is part of it—of manifest destiny: It's our future to grow. We're creating an economic, cultural, entertainment mecca that many people wish to come to. What can be wrong with that? But there's a failure on all fronts, at almost every level, to meaningfully engage the public about potential impacts and alternatives. It's all behind closed doors."

Reid's supporters and their pro-development cohorts see much of the criticism of the senator as alarmist and unfair. In his statement, Reid said he is proud of his land bills for setting aside 2.5 million acres of wilderness in Nevada over the past eight years, adding that those laws have "created transparent and limited processes to guide the growth." As for the pipeline, Reid acknowledged that population explosion and drought are posing "difficult choices" for Nevada. Federal and state regulators are reviewing the pipeline plan, he wrote, and "will have final say on its development." Southern Nevada's water managers say there's nothing to worry about with the pipeline, if for no other reason than that the district is bound by an accord it signed in 2006 with several agencies of the Department of the Interior that will force the state water authority to shut off the pumps at the first sign of trouble. "This organization is about as environmentally friendly as you'll ever find a water agency," says Richard Wimmer, the Southern Nevada Water Authority's deputy general manager. "But we'll never know what the precise impacts are until we stress the system."

There's a reason 87 percent of Nevada's land is still owned by the federal government. The U.S. secured the territory at gunpoint from Mexico in 1848, but except for some isolated homesteads and mining claims, few people wanted to settle in the arid plains or jagged mountain ranges that thrust upward from the desert floor every 30 miles or so across the state. The area's largest private landowner was once Howard Hughes, who made an unsuccessful attempt in the 1950s to move his aircraft company from Los Angeles to a 25,000-acre site he bought west of the Las Vegas Strip. The eccentric billionaire also acquired several high-rise casinos in the center of town. (Paranoid and addled by drugs, he holed up for years in the penthouse of one of them.) The region's other land baron has always been the U.S. government. "A common fallacy is that growth in Las Vegas just happened," says Daniel Patterson, a former ecologist at the U.S. Bureau of Land Management, the federal agency that controls two-thirds of all land in the state. "It didn't. This is the town that Congress built."