Tuesday, Sept. 28, 2004 | 11:04 a.m.
Southern Nevada Water Authority officials are considering spending tens of millions of dollars on a third intake pipe to draw water from Lake Mead.
A third pipe, which would be deeper than the existing two, might be needed to ensure access to drinking water if the lake level continues dropping, officials said.
Water officials said Monday it is too early in the evaluation of a third intake to say how much it could cost or when it would be built. The second intake, which became operational in 2002, cost $80 million and took two years to construct, water authority spokesman Vince Alberta said.
Water authority board Chairwoman Amanda Cyphers, who is also a Henderson councilwoman, and board Vice Chairman Rory Reid, also a Clark County commissioner, both supported continued study of a third intake for the drought-stricken lake, which provides about 90 percent of the water used in the Las Vegas Valley. The two said they needed more information before deciding whether to support a third intake.
"As the lake level starts to decline, the quality of the water starts to decline," Cyphers said. "The clarity is better at lower levels, and we need to find solutions."
The third intake proposal is "an idea that's being thought through," she said. "It's better to be prepared than to be caught short."
The water authority is the water wholesaler for Las Vegas, Clark County, Henderson, North Las Vegas and Boulder City, and it is led by a board comprising elected officials from those local governments.
Reid said the water authority at least needs to study the issue because the continued emptying of the lake creates efficiency and water quality problems for the existing intakes.
"We need to move forward with the study," he said.
During a Monday meeting with a citizens advisory committee looking at future water sources, water authority Director of Engineering Marc Jensen said the water authority will need a new intake to continue drawing as much water as it currently does from the lake. A new intake would essentially replace the first intake, which he said would eventually become inoperable if the water level continues falling.
The first intake, built in 1971, took in water at 1,050 feet above sea level until July, when an extension was completed that brought the opening of that intake down to 1,000 feet above sea level. The second intake also draws from 1,000 feet.
But even with the extension, the first intake wouldn't work if the lake level dropped below 1,050 feet, Jensen said. This is because the pumps the intake is connected to would not work once above the water level. The water level in Lake Mead is now about 1,126 feet above sea level and has dropped about 90 feet during the past five years.
The third intake would be placed deeper than both of the existing intakes. In addition to simply being able to get the water out of the lake, a deeper intake would also draw higher quality water from the lake.
Roughly the top 50 feet of water in the lake is in what's called a thermocline, or layer of water that is warmer, thanks to the sun, and home to higher concentrations of pollutants and algae. As the lake level drops, the thermocline comes closer to the existing intakes.
Water authority Deputy General Manager Kay Brothers said the staff will probably have cost estimates, a time line and location for a possible third intake prepared by early next year.
Alberta said the matter could go to the water authority board for a formal presentation soon thereafter.
archive
