Experiment to give Lake Mead boost

Suzanne Struglinski

Friday, Nov. 19, 2004 | 10:40 a.m.

WASHINGTON -- A federal water release experiment to learn more about the Colorado River's ecosystem will give Lake Mead a 2 1/2 foot boost by next week.

The Bureau of Reclamation will release 340,800 acre-feet of water from Utah's Lake Powell by opening valves in Glen Canyon Dam on Sunday. The water will flow down the Colorado River, through the Grand Canyon and eventually end up in Lake Mead.

A drought has left Lake Mead about 83 feet below its ideal level, so the additional water will be the proverbial drop in the bucket. The water is not being released to help the lake, but instead to move sediment to rebuild beaches, help improve endangered fish habitat and learn more about the river.

"A two-foot difference does not sound like much when you consider how big Lake Mead is, so many regular beach-users might not notice the difference," said Lake Mead National Recreation spokeswoman Roxanne Dey. "However, boaters will notice the difference because for every vertical foot the lake increases, that could translate to 10 to 20 feet of shoreline depending on the slope.

"At Hemenway Harbor, for instance, the shoreline will increase at least 20 feet. Boaters will find it easier to launch."

Dey said it also will be easier to launch boats at Callville Bay, where regional and national fishing tournaments originate. Because of varying slopes, Dey said she did not know approximately how much more shoreline will be added to Callville Bay.

Dey said park officials also will have to move the courtesy docks in to accommodate for the sudden rise. Those include the headwalks and some of the walkway fingers. The distances will vary, again because of the slope, Dey said, noting "we are constantly reconfiguring the courtesy docks."

The lake level currently is at 1,128 feet. Normal is 1,180 to 1,200. Full is at 1,220 feet, the level at which water goes over the spillway gates at Hoover Dam, Dey said.

The release of the water from upstream of Lake Mead will start early Sunday morning and run for about 90 hours, with 60 hours of peak flow, according to the bureau.

"It's not just releasing water to release water, it has a specific purpose," said Bob Walsh, spokesman for the Bureau of Reclamation's Lower Colorado Office in Boulder City.

Lake Mead will rise gradually over a few days, Walsh said.

A.B. Wade, U.S. Geological Survey spokeswoman, explained that the dams prevent 96 percent of the sediment that would normally flow through the river from moving anywhere, so releasing the water will help restore that flow and let scientists study the ecosystem.

Wade said her agency will be looking at how sandbars and beaches along the Colorado will form with such a large release of water. She expects a million tons of sediment to be moved through the water.

Sunday's release is contingent on the approval of an environmental impact statement on the release, which is expected today.