BOULDER, Colo. (CBS)-- Flash flooding in Colorado has left two people dead and the widespread high waters are keeping search and rescue teams from reaching stranded residents and motorists in Boulder and nearby mountain communities as heavy rains hammered northern Colorado on Thursday.
Boulder Office of Emergency Management spokeswoman Gabrielle Boerkircher said volunteers are trying to help stranded people until emergency crews can arrive because many roads are impassable.
Boerkircher said one person was killed when a structure collapsed in Jamestown.
Colorado Springs spokeswoman Kim Melchor said police conducting flood patrols found a body in the water on the west side of the city Thursday morning after warnings were issued for flooding from a wildfire burn scar west of town.
John Schulz, spokesman for the Larimer County Sheriff's Department, said a series of four dams in the Big Elk Meadows area all overtopped overnight, and one -- the Meadow Lake Dam -- actually broke. Residents in at least four homes are stranded in flood water.
In Lafayette, a bridge washed out near Highway 287 and Dillon Road, sending at least three vehicles into the water. Emergency crews pulled one man alive from a car after it was tipped upside down in the raging torrent.
Creeks were expected to continue to spill over their banks and threaten local homes and roadways as rainfall continued.
Jamestown and Four Mile Canyon were under mandatory evacuation and residents of Boulder City and areas north of there were being asked to stay in their homes or to seek higher ground, said Andrew Barth of Boulder County's Office of Emergency Management.
Barth said several structures in mountainous areas have been lost.
Boulder Emergency Management spokeswoman Gabrielle Boerkircher said about 400 students at the University of Colorado-Boulder were evacuated. The campus was shutting down Thursday because of the flooding.
Roads in some parts of the county had up to a foot of standing water on them and were closed, reports CBS Denver station KCNC. The local fire department and sheriff's department helped people stuck on flooded streets.
The Weather Service posted flash flood warnings for Boulder County and for parts of Broomfield, Adams, Weld, Larimer, and El Paso counties. KCNC forecasters predicted rain, heavy at times, and isolated storms into the weekend.
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