DENVER (September 14, 2013)--National Guard troops resumed truck convoys Saturday to rescue residents stranded by floodwater in the cut-off Colorado community of Lyons north of Boulder.
An estimated 2,500 residents were being evacuated in an operation that began Friday.
Helicopters were being used to airlift 295 residents from the small mountain mining town of Jamestown northwest of Boulder.
The National Guard was also airdropping food, water and other supplies to people stranded in narrow canyons in the Rocky Mountain foothills.
Evacuations are voluntary, but those who choose to stay with their homes could face weeks without power, water, sewer or cellphone service.
Days of heavy rain sent water rushing from the mountains into communities below, inundating farms and destroyed roads and bridges, turning neighborhoods and towns into islands.
The flooding affects parts of a 4,500-square-mile area, almost the size of Connecticut.
The flooding has caused at least four deaths.
Officials in hard-hit Boulder County say more than 170 people are still unaccounted for, but say that just means they haven't been heard from, not that they're actually missing.