BOULDER, Colo. - A storm blasted the area with more than seven inches of rain and touched off severe flash flooding Thursday, sweeping motorists from roadways, destroying a dam and killing at least two people.
KUSA-TV reports that one person was killed in the collapse of a home in Nederland, and Colorado Springs police said they found a second victim while patrolling in a flood area west of the city.
Police scanners buzzed with emergencies as rescuers aided motorists caught in high wate. One officer told dispatchers about "banging inside the cars" as passengers sought help getting out.
Another reported a car submerged upside down, with at least one person missing.
Footage from KCNC-TV showed the dramatic rescue of a man from a car that was sitting upside down in a flooded creek in Lafayette. The man was pulled to safety as the creek slowly swamped his vehicle. Lafayette Battalion Chief Dan Garrett told CNN that his crews also pulled to other people to safety from vehicles overwhelmed by floodwaters.
One firefighter was reported to be stuck in a tree in Lefthand Canyon in Boulder County after a "wall of water" 15 to 20 feet high roared through the canyon, according to the Boulder County sheriff's office. Officers on scene requested a dive team to help with the rescue, but none was immediately available locally.
"We have a lot of boat, but not divers," one officer told the radio dispatcher.
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Near the town of Lyons, about 15 miles north of Boulder, rescuers repeatedly found themselves turned back by floodwaters of the St. Vrain Creek.
Nick Christensen with the Larimer County Sheriff's Office was following a deputy along state Highway 66 into Lyons when both full-sized SUVs started being pushed around by water running down the road.
Colorado Department of Transportation workers said they saw water flowing over the road's 27-inch-high guardrails. Deputies and road crews were trying to access the area to check for stranded residents and damage.
"There were homes and businesses that were receiving significant impact," said Christensen. "It was flowing in waves down the road. There's definitely a lot of water."
Boulder Office of Emergency Management spokeswoman Gabrielle Boerkircher said volunteers all across the area were trying to help stranded people until emergency crews can arrive because many roads are impassable.
Coal Creek Canyon northwest of Denver was closed because of a washed-out highway.
The Larimer County office of emergency information said an earthen dam in the Big Elk Meadows area southeast of Estes Park gave way and residents of Pinewood Springs and Blue Mountain were ordered to be ready to evacuate.
Residents of the Big Elk Meadows area were told by a recorded message they "should be seeking higher ground immediately."
The National Weather Service, citing Boulder officials, said multiple homes in the area have collapsed and urged people in the area to move to higher ground.
The NWS issued a flash flood warning for Northern Jefferson and Boulder counties, saying that in many locations this is an "extremely dangerous and life threatening situation."
The Weather Service said early Thursday that more than four inches of rain had fallen in some areas since noon Wednesday.
Meanwhile, about 400 students at the University of Colorado housing in Boulder were evacuated and classes canceled Thursday because of the flooding, Boekircher said.
"We've asked people in low-lying areas all through the county to evacuate," said Andrew Barth, another Emergency Management spokesman.