About 600 people who had been stranded by a mudslide that hit the Fairmont Hot Springs Resort in southeastern B.C. on Sunday are now able to leave the area, resort officials say.

The mudslide swept down a creek bed through the popular resort town north of Cranbrook at about 4:30 p.m. MT Sunday, as people scrambled to get out of the way.

On Monday morning, most roads in the area were reopened after the mudslide closed Highway 93/95 for several hours on Sunday, forcing the evacuation of large parts of the resort.

Road access to the RV park and campground was reopened about 2:30 p.m. MT Monday, spokesman Marke Dickson said in a release.

"Guests have been able to move freely to and from the RV park, Dickson said. "Parts of the resort are still closed, they are mostly focusing on cleanup now."

The cleanup is expected to be a mammoth job.

"The size and scope of the debris field is staggering," said Loree Duczek, emergency program information officer for the Regional District of East Kootenay Columbia Valley.

"Debris from further upstream created an earth dam, and when it let go late yesterday afternoon, the force sent trees and boulders through neighbourhoods, at one point sweeping vehicles and a large propane tank downstream."

Campers at the Fairmont Hot Springs Resort were stranded when the water and debris tore out the access bridge between the resort and the campground.

"Some family members were separated on opposite sides of the creek, and the resort staff jumped in to try to make sure campers who were unable to return to their campsites were looked after," said Duczek.

Dickson said workers were able to lay in a huge culvert pipe and cover it with dirt, temporarily replacing the washed-out bridge.

Camper Adel Tabsh had said he was prepared for an extended stay.

"We have food, so if it lasts only for a couple of days, we'll be OK," said Tabsh.

People scrambled to get out of the way as the surge of mud and water swept down from high on the mountainside moments after a lifeguard working at the town's hot spring pools noticed the water was getting murky and sounded the alarm, according to Wendy Booth, a director with the East Kootenay Regional District.

"He started to see a bit of brown coming into the pool, into the hot springs pools and so he went up to the intake and saw trees and stuff coming down so he ran back and called 911 and cleared the pools and then the whole thing came down," said Booth.

The torrent of water, mud, boulders, logs and at least one car hit the Fairmont Mountainside Vacation Villas resort and its golf course, and forced the evacuation of four homes.

Search and rescue manager Ian Cunnings said about 100 people were displaced, but so far there have been no reports of major injuries or people missing.

"There have been subjects rescued by the fire department as well as by [search and rescue] resources using rope and helicopter," said Cunnings.

Officials were to get a better look at the damage as water receded on Monday morning, but say it does not appear that any structures have been destroyed, although the damage is extensive.

Witness Doug Clovechok watched the mudslide rush past one resort and toward another down the road.

"There's millions of dollars of damage done here to the resort and it's beyond belief," said Clovechok.

Crews are also working to clear the creek of major debris in the hope of preventing more flooding, but there is more rain in the forecast over the next three days, making for unstable conditions.