Dangerous levels of bacteria polluting LV wash

Levels of bacteria 1,200 times higher than considered safe are contaminating the Las Vegas Wash in a plume of murky water, said a scientist tracking the pollution flowing into Lake Mead from storm runoff this week.

"The research is quite dramatic and is producing valuable data," said James LaBounty, a Bureau of Reclamation scientist who for eight years has been studying the polluted plume that runs like a river within the lake. No one knows how fast the plume flows, he said.

The National Park Service has posted signs in the wash that warn people to avoid contact with the water, since treated sewage, surface runoff and floodwaters all contribute to the pollution.

Federal and local scientists continued testing the waters today after they discovered higher-than-expected levels of fecal coliform and E. coli in the wash. The research will help scientists to protect Southern Nevada's water quality as Lake Mead serves as both a source for drinking and recreation.

Fecal coliform indicates disease-causing organisms are present in the water. The coliform count in the Las Vegas Wash measured above 240,000 cells per 100 milliliters. The level that prohibits body contact is 200.

Normal counts in the wash seldom range above 30,000, said Debra Bolding, the supervisor for the city of Las Vegas wastewater treatment plant. "It's the first time we've seen such high levels," she said.

E. coli, an organism that can cause bloody diarrhea in some cases, was as high as the coliform counts, about 1,200 times above normal.

The concern is how long the contaminants will continue entering local waters and how far they will go, Bolding said. Coliforms indicate a disease-causing organism is present. E. coli come from the feces of all warm-blooded animals, but certain strains cause severe diarrhea.

If the contamination stays in the plume moving through the lake, it will not pose a threat to swimmers or boaters because it is more than 30 feet below the surface. Scientists are testing surface waters because the contaminants become dangerous if swallowed, inhaled or ingested.

Possible sources of the contaminants include fecal matter or sediments stirred by the floodwaters. The nature of the lake in the summer months makes it unlikely that the plume could be mixed with the surface water and become dangerous to bathers, scientists say.

Bureau of Reclamation scientists and biologist Larry Paulson braved wind, waves and lightning to collect the samples this week. Crews collected samples twice a day for the first three days after Monday's storm from Las Vegas Wash, Las Vegas Bay and the lake.

"It's a very urgent situation to deal with the water quality," Paulson said. "It's time we deal with the problem."

Throughout this weekend, the Bureau of Reclamation crew will continue to collect samples once a day.

The Regional Flood Control District is paying about $3,000 for the laboratory workers' overtime, said Kevin Eubanks of RFCD, who leads a committee trying to discover if the contaminated storm water turns Las Vegas Bay unfit for swimming.

If warnings to swimmers and boaters at certain areas in the lake or the bay become necessary, the Nevada Division of Environmental Protection and the National Park Service would issue a joint warning.

Allen Biaggi, NDEP director, and Bill Burke of the National Park Service, said affected areas would be posted by both agencies, if necessary. No closures have ever been made at the Lake Mead National Recreation Area.

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