Now the proposal - which calls for tapping aquifers under the arid valleys of eastern Nevada and western Utah and shipping nearly 200,000 acre-feet of water annually to Las Vegas via a pipeline network - goes before the person who counts most: Nevada state engineer Tracy Taylor.

Three weeks of hearings commence in Carson City on Monday to assess whether the authority's $2 billion project should be approved. For both sides, the stakes could not be higher.

The water authority's general manager, Pat Mulroy, says the very future of Las Vegas and surrounding Clark County is on the line. With its Colorado River allotment of water about maxed out, Mulroy has argued that her agency has no choice but to seek alternatives for one of the nation's fastest-growing metropolitan areas.

"My job is to protect the water resources of a community of 1.8 million people," she told The Salt Lake Tribune earlier this summer. "Nevada has no backup [water] supply. The only solution is to plumb a system that is separate from the Colorado River."

Added Mulroy: "We understand that there are short-term and long-term concerns."

That's putting it mildly. A small, but well-organized coalition of ranchers, environmentalists and political officials from eastern Nevada and western Utah has campaigned relentlessly against the authority's plan, warning that taking such large amounts of groundwater out of a cluster of Great Basin valleys will dry up and devastate the region's ecosystem - and kill its ranching industry.

Among those raising concerns has been the LDS Church, which owns a cattle ranch in Spring Valley, west of Great Basin National Park.

"This is a balanced system and a delicate system. Nobody knows that better than those who live and work out here," Callao rancher Dennis Timm said earlier this month. "If we start unbalancing this system, it's going to have far-reaching effects, beyond this community."

Adding to the controversy has been the authority's acknowledged desire to fast-track the project. It is seeking state approval for its proposal in advance of the completion of a pair of ongoing environmental studies. One, by the U.S. Geological Survey, is analyzing impacts the project would have on the area's groundwater resources. The other, by the Bureau of Land management, is assessing on-the-ground impacts.

The water authority has also rushed along Utah officials, who must approve the project before the authority can begin taking water from aquifers it shares with the Beehive State.

Utah is currently negotiating a water-sharing agreement with Nevada over those aquifers. It is expected to be completed sometime this fall, before the USGS and BLM studies are completed. And that has drawn the ire of the authority's opponents.

"These agreements are being penciled in before the science is in. This, we cannot understand," said rancher Don Johnson, also from Callao.

Michael Styler, the state's Department of Natural Resources director, insists that Utah's water rights will be sufficiently protected. Any deal with Nevada, he said earlier this month, will have to be flexible enough to accommodate at least some of the USGS and BLM findings.

But the negotiations with Nevada have also been conducted in a high-pressure environment. Authority director Mulroy has implied that Utah could face trouble with its own water projects if it does not sign off on the Nevada project. And Nevada Sen. Harry Reid, the Senate minority leader, has applied additional political pressure to get a Utah-Nevada pact done.

The water authority has spent hundreds of thousands of dollars to get its message across. It has hired lobbyists in both Washington, D.C., and Salt Lake City, and in late August unveiled what it says will be a six-month newspaper and radio ad campaign meant to counter the opposition's arguments.

"We are very cognizant of our role in environmental stewardship," authority spokesman Scott Huntley told the Las Vegas Review-Journal.

Mulroy has also played political hardball, suggesting last month that if Tracy, the state engineer, issues an unfavorable decision, he could be replaced.

"The governor can remove the state engineer and appoint a new one," she told the Las Vegas Sun.

Taylor last month rejected most of the authority's petition to restrict his consideration of environmental issues in the hearings, which run through Sept. 29.

jbaird@sltrib.com

See WATER, B6