Search and rescue teams have been using boats and helicopters to pull stranded residents to safety in areas where flash floods have toppled buildings, washed out roads and inundated farmland.
The flooding began last week and was triggered by unusually heavy late-summer storms that soaked Colorado’s biggest urban centres, from Fort Collins near the Wyoming border south through Boulder, Denver and Colorado Springs.
Boulder and a string of other towns along the Front Range of the Rockies north of Denver were especially hard hit as water poured down rain-soaked mountains and spilled through canyons that funnelled the runoff into populated areas.
Lyons, a town north of Boulder, was virtually cut off when floodwaters washed out US Route 36, stranding residents without water and power for 48 hours.
At least four people were killed, including a couple swept away in floodwaters after stopping their car north-west of Boulder. The man’s body was recovered on Thursday and the woman’s body was found on Friday.