Boulder, Colorado (CNN) — Help has arrived for Lyons, the small town cut off by flooding in Colorado.
The Colorado National Guard began evacuating the entire town of about 2,000 at daybreak, Gov. John Hickenlooper said.
But the outlook was less upbeat for a broad swath of northern Colorado. State transportation officials issued an emergency alert to residents in four Colorado counties hit hardest by flooding, warning them to stay off roads because many are unstable and could give way without notice. Interstate 25 was closed.
Authorities warned that more rain was on the way, posing the threat of additional flooding.
In Fort Collins, some residents had been urged to leave their homes. And in Denver, police responded when a man was swept into a drainage pipe with his dog. Both were saved after traveling two blocks in the water, police said on Twitter.
The situation is the result of 6 to 8 inches of rain dumped on parts of northeastern Colorado in the last 24 hours, the National Weather Service said. The rains sent virtually every waterway in Boulder County, one of the hardest-hit areas, coursing out of its banks, and massive water flows washed away roads and bridges, flooded homes and stressed numerous other bridges.