High level of bacteria found in LV Wash

Federal and local scientists testing the Las Vegas Wash after Monday's storm discovered high levels of bacteria from flood runoff.

Fecal coliform, an organism that indicates bacteria in the water, registered above 240,000 cells per milliliter. Normal counts range from 10,000 to 90,000, said Debra Bolding, the microbiology supervisor for the city of Las Vegas treatment plant. It was the first time Bolding had seen such high levels of the organism, she said.

E. coli, an organism that can cause bloody diarrhea in some cases, was also 20 times higher than normal. "They are higher than the typical count," Bolding said Wednesday night.

There is no limit for these organisms in the Las Vegas Wash, since no one is supposed to come in contact with its waters draining the Las Vegas Valley. Bolding said tests will continue to check floodwaters reaching Lake Mead, Southern Nevada's major source of drinking water.

The Lake Mead Water Quality Forum, a group of scientists from federal, state and local agencies, had planned to test the wash after floods. "It took a long time for something to happen, but it finally did," Bolding said of this week's storms.

Las Vegas biologist Larry Paulson said he has urged such testing in the wash for years. "This has got to be reason for concern," he said. If bacteria levels increase in Lake Mead's waters, the National Park Service might issue a warning to swimmers and boaters. No such warning has ever been issued for the lake.

Las Vegas draws its drinking water six miles downstream from the Las Vegas Wash, but the water is extensively treated before reaching home taps.

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