$2.5 million for lake project is approved

Friday, Dec. 19, 2003 | 11:10 a.m.

Facing a drought that is dropping Lake Mead's water level, the Southern Nevada Water Authority's board on Thursday approved $2.5 million to buy materials to extend the upper and original intake through which nearly all of the region's drinking water flows.

Like conservation rules that have prompted residents and businesses throughout the region to cut back on water use, the intake extension is a by-product of the declining water levels caused by drought.

The need for the project comes at a time when the lake level is at 1,139 feet and falling. The intake now brings in water at 1,050 feet. Marc Jensen, water authority engineering director, said the main concern is not that the level would fall below the intake mouth. Although that is a concern, even after more than four years of drought, it still looks unlikely, he said.

As the lake level falls, warmer, less pure water at the surface comes closer to the vortex created at the intake. The cleanest water comes from deeper in the lake, Jensen said.

"Water quality in Lake Mead in general is very good, but we're anxious to get the best water quality we can for our community water supply," he said. "It's not bad quality of water, but we're starting to see some higher temperatures, with higher organic content."

The new pipe would bring water from about 980 feet above sea level, 70 feet below where the intake is now.

The water authority, which is the water wholesaler bringing the resource to purveyors in Las Vegas, unincorporated Clark County, North Las Vegas, Henderson and Boulder City, is scheduled to award a bid next month to install the intake extension.

Jensen said the cost for installation could be $3 million to $5 million.

The design and potentially the cost changed from the original plan advanced in July, which would have placed a $5 million plastic, circular sleeve from the top of the water line to deep around the intake. Jensen said the pipe extension has several advantages to the plastic sleeve concept originally considered.

The extension would have no visual impact on the lake's recreational users, unlike the plastic sleeve. Perhaps more importantly, the extension would be a permanent addition, Jensen explained. Unlike the huge metal pipe, the sleeve would have to be constantly maintained to keep it working effectively.

A permanent installation is increasingly important as the drought hitting the Rocky Mountains drags on through a fifth year. Kay Brothers, water authority deputy general manager, said last year's snow in the mountains, the source of the Colorado River and Lake Mead, was just a little more than half of what it should be.

At a time when river watchers and water officials were hoping for an above-average year, so far the total is about 88 percent of normal, Brothers said.

Although the water authority is looking for a long-term solution, they also want it soon.

The timetable for the project pegs the start of construction in February or March, with completion coming in June. The timetable is unusual for big public works projects, Jensen said.

"It's very aggressive," he said.

The water authority already has needed approval for the work from the National Park Service, the Nevada Department of Environmental Protection, the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service, Jensen said.

One of the reasons that the water authority wants to complete the work quickly is that heavy demand for water begins in June. The water authority has a second water intake that opened just a few years ago, but the older intake, which provides Southern Nevada with 600 million gallons of water a day, is still the primary feeder for the water system.

The older intake will have to be shut down for limited periods, but customers aren't likely to experience any problems, Jensen said. The reservoirs that pump water to homes and businesses can hold billions of gallons, collectively, so they can withstand short-term interruptions.

Also, the newer, lower intake will continue to feed water to the system, he said.