Alamosa officials won't be able to shut down the town's water system to disinfect it until at least Saturday because an adequate backup water supply isn't in place yet.
Polly White, spokeswoman for the Colorado Division of Emergency Management, said the state is still searching for ways to supply water to the town for the estimated two weeks it will take to flush the water system. "We're trying to get to the point where we can say 'OK, we have enough,'" White said.
Alamosa and the state are also scrambling to make sure everyone in the community is warned before the flushing begins. No tap water can be used once the process starts. "If they think they have some people out of the loop, they're going to go door-to-door," White said. "Every single resident who could be affected has to be notified. Once they begin the flushing, the stuff that's coming out of the pipe is even worse than what they're dealing with now."
The flushing process dislodges sediment in the system which takes some time to clear. Alamosa was struck by a rare, water-born salmonella outbreak this week that has sickened at least 111 residents.
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http://www.rockymountainnews.com/news/2008/mar/20/Alamosa-declares-water-emergency/