UNLV institute joins fight to clean up lake

Tuesday, Nov. 28, 2000 | 11:32 a.m.

A new research institute at UNLV is delving into the depths of Lake Mead to ensure better water quality.

UNLV has launched the Lake Mead/Mohave Research Institute, an organization dedicated to researching environmental issues in Southern Nevada's water, founding Director Mark Rudin said.

Lake Mead supplies most of the drinking water for the Las Vegas Valley.

The Las Vegas Wash drains sediments and pollution from the valley and its surroundings, a total area of 1,650 square miles, into the lake, creating a plume in the Las Vegas Bay.

The pollutants include chemicals, treated wastewater, fertilizers, pesticides and insecticides along with surface scum such as motor oil. Layered at the bottom of the lake, the sediments tell a story of the Las Vegas Valley.

The institute's work began with mapping the bottom of the Las Vegas Wash and the Las Vegas Bay, but next year a portrait of the whole lake may be possible, Rudin, a UNLV health physics professor, said.

With $300,000 given by Congress to the U.S. Geological Survey at Woods Hole, Mass., the institute will team up with the USGS next year and complete a picture of the lake's bottom, Rudin said.

"No one has mapped the entire bottom of the lake before, to my knowledge," Rudin said.

The institute also is looking for fingerprints in the lake's sediments left by chemical pollutants and radiation from nuclear weapons experiments conducted over four decades at the Nevada Test Site, 65 miles northwest of Las Vegas. Rudin has found evidence of nuclear weapons fallout.

By teaming up with the UNLV Geoscience Department, the institute plans to collect and analyze sediments from the bottom of the wash, the bay and the lake.

"We're expecting the sediments to give us a history of the pollution in the lake," Rudin said.

So much attention has been centered on the Las Vegas Wash, that many people lose sight of the whole lake, Rudin said.

Meanwhile, Clark County is working to revive the Las Vegas Wash. Thirty years ago 2,000 acres of wetlands helped filter out pollutants and chemicals before they reached the lake.

Today fewer than 200 acres of marsh plants remain, and runoff is increasing.

The Bureau of Reclamation and the Southern Nevada Water Authority are planting "floating" wetlands, a concept lake expert James LaBounty learned from Japanese water specialists. LaBounty has studied Lake Mead for 10 years with the Bureau of Reclamation and is continuing that work with the water authority.

The floating wetlands are two galvanized steel frames 122 feet long and 26 feet wide that look similar to common boat slips, anchored in 20 feet of water.

Covered with coconut husk fibers, the manmade wetlands will be planted with native flora such as cattails, rushes, sedges, spike rushes and bulrushes over the winter.

"The study of the wetlands provides another opportunity to gather data on improving water quality in the wash," said John Johnson, deputy director of the Bureau of Reclamation's Lower Colorado Region Resource Management Office.

In the next few months researchers will monitor and evaluate the floating wetlands.

The scientists are looking for improved water in the bay as the wetlands act as filters.

The wetlands could also provide a haven for threatened or endangered species -- above or below the water -- scientists said.