Fissures could threaten water pipeline

Wednesday, Sept. 21, 2005 | 11:03 a.m.

Hydrologist David Donovan of the Southern Nevada Water Authority is investigating cracks or splits in the Earth's surface along a possible water pipeline route that could "pose a significant challenge" to designing it.

The fissures, located in eastern Nevada, will be discussed by Donovan in a presentation on Lincoln County's Dry Lake Valley during the 48th annual meeting of the Association of Engineering Geologists opening today in Las Vegas.

In the early 1980s, Donovan noted in an introduction to his paper, the Air Force investigated the fissures when the Reagan administration considered building the MX nuclear missile system in Nevada.

The U.S. Geological Survey reported then that several of the fissures were active and could move.

The fissures could pose a threat that could disrupt water delivery through a future pipeline if they continue to expand or if an earthquake occurred, geology experts said.

The fissure system extends in an area of the valley for a distance of about 300 feet long and is about 75 feet wide, said Ann Backstrom, another geologist presenting information about the Dry Lake fissures and whether they are expanding. Backstrom works for the engineering firm Kleinfelder in Las Vegas.

The appearance of an enlarging fissure system was discovered in 1990.

Following a heavy rainfall in August 2003, the fissures opened at the ground's surface near a proposed power substation site, Backstrom said, near the other area of fissures found earlier.

The Water Authority is studying the area in detail and examining rocks and soil along the route, said Roger Buehrer, a Water Authority spokesman.

Fissures, earthquake faults and other geological problems are often discovered during investigations along utility corridors, Buehrer said. The Water Authority plans to conduct extensive studies of the area before designing any pipeline, he said.

During the Association of Engineering Geologists' meeting Burt Slemmons, a noted Nevada geologist, will be recognized as honorary member, given to those persons whose careers exemplified the ideals of the Association of Engineering Geologists.

Slemmons is a geoscience professor emeritus at UNR and retired to Las Vegas.