Nevada's state water resources chief has approved a plan that could have groundwater from rural Nevada flowing through Las Vegas faucets by 2007.
Last week’s ruling by State Engineer Hugh Ricci lets the Southern Nevada Water Authority pump up to 8,905 acre-feet of groundwater a year from four basins in northwest Clark and southwest Lincoln counties. An acre-foot is about 326,000 gallons, or enough water for one to two households a year.
The water authority had sought almost twice as much water as Ricci granted through the Nevada Division of Water Resources. Officials said that with reuse and conservation, the supply could serve 20,000 households.
Water Authority General Manager Pat Mulroy called the ruling "a very conservative but a fair and balanced approach."
Officials with Nye County and the Sierra Club of Southern Nevada, which opposed the pumping plan, said no decision had been immediately made whether to challenge Ricci's ruling. Opponents have 30 days to appeal in state court.
Ricci's ruling requires the authority to gauge any effect pumping has on wells and natural springs in the surrounding Tikaboo and Three Lakes valley basins.
During hearings last year, opponents argued that too little was known about the basins and the underground water supply to approve large-scale pumping.
But Ricci said pumping was the only way to learn more. If water sources in surrounding areas are harmed, Ricci said the authority could be required to cut or stop pumping.
Conservationists assert that by the time effects become noticeable, delicate water resources and species will be harmed.
"There aren't a lot of streams in the Mojave Desert but there are isolated springs," said Jane Feldman, Sierra Club conservation chairwoman in Las Vegas. "That's where our biodiversity is. That's where plants and animals thrive."
Ricci said the water authority could be required to mitigate any damage with monetary payments or by injecting water underground.
Water authority officials have put the cost of developing the water rights approved Tuesday at about $213 million, including a $55 million pipeline to connect new wells to the Las Vegas water system.
The authority has other far-reaching plans to tap groundwater in rural Nye, Lincoln and White Pine counties to supply Las Vegas and reduce dependence on the Colorado River.
The Nye County Board of Commissioners has formally protested the plan and hired experts to help protect the county's interest, especially in Pahrump, which has been in an overdraft situation for the past couple of years, meaning residents consume more water each year than is provided by runoff from the Spring Mountains, Pahrump's key water source.
The plans to tap groundwater were accelerated last year in response to the region's record drought, now in its sixth year.