(CBS News) LYONS, Colo. -- In Colorado, the damage from this week's floods spans 17 counties and 2,000 square miles. Roads are gone. Houses destroyed. Eighty-four people remain unaccounted for, and seven are confirmed dead, including one in Lyons, a town that may have seen the worst of the flooding.
The water that rushed through Lyons might have claimed more lives, were it not for Dan Barber's obsession.
"So you have two rivers that have flooded in the past, come together right here in downtown Lyons, and to me that was very concerning," Barber says.
Mountain runoff from 225 square miles collects, but Lyons did not have a flood warning system. Barber was the county sheriff's sergeant assigned to the town. He spent years trying to convince town leaders to spend $25,000 on a new warning siren.
"I made a three-foot-by-three-foot cookie dough map by overlaying cookie dough as mountains and ridges and valleys over the town map, and showed them that this is how the water's going to flow and how it will cut off certain parts of the town, and they got it, and that's exactly what happened" Barber says.
The sirens were installed in 2008. On Thursday, they woke up Tammy Graboski's family.
"I knew the sound, knew something was going on, was alerted immediately," she says.
Nicholas Angelo is a former mayor of Lyons.
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"I know that there are so many that were down by the river that got to get out, because of that, that system saved between 200 and 300 lives, probably," Angelo says.
"One of the deputies texted me that my cookie-dough map was spot on," Barber says.
A map that even his wife had thought was ridiculous.
"She laughed at me, as well as many people did," he says. "They're not laughing anymore."