Drinking filtered water may not be such a bad idea afterall for Las Vegas residents- or others, as well. 
Last week the Las Vegas Valley Water District pulled a water sample from the Las Vegas community water supply for testing– and it tested positive for the E. coli bacteria.
But officials say the Las Vegas water supply was never compromised and there was no risk to the public- a mere passing reference to it was mentioned only once in the water district’s annual water quality report, with no real explanation provided. The water district sent almost 500,000 copies of the report.
With about 90 percent of the Las Vegas water supply coming from Lake Mead, Nevada officials and regulators insist there is no need to start boiling your tap water just yet, but they also can’t explain exactly why the water sample taken in August tested positive for the sometimes deadly E. coli bacteria because it could find no other trace of it in any follow-up tests.
According to Nevada state records, the incident was the first time E. coli has shown up in a district sample in at least five years.
The water district draws more than 380 water samples each month from almost a thousand different locations throughout its Las Vegas water distribution system.
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