The Bear Fire burning in Dinosaur National Monument gathered enough fury over the weekend to jump the Yampa River and threaten private land.
But helicopters carrying water and slurry drew a line of defense in the piand juniper that fuels the blaze.
About 4,500 acres of land are burning near the east entrance in Dinosaur National Monument.
The wildfire, which started Friday and is believed to have been started by humans, scared firefighters and officials Saturday afternoon when it jumped north across the Yampa River near the mouth of Thanksgiving Gorge, officials said.
Thanksgiving Gorge involves steep, inaccessible terrain and officials were concerned that the fire would spread out of the gorge and head toward Bureau of Land Management and private property, Dinosaur National Monument Superintendent Chas Cartwright said.
But an intense effort by aircraft has kept the fire's growth in check thus far.
"When it spotted over to the north side of the Yampa, there was huge concern about the people who live in Douglas and Greystone," Cartwright said. "If it would have gotten up on top of the gorge there was solid pijuniper that would have taken the fire to BLM and private land. But the helicopters hit it hard with retardant and water."
The Craig Interagency Dispatch Center was predicting evacuations Sunday but due to success that day, no evacuations are planned, officials said Monday.
The Moffat County Sheriff's office notified people in the Douglas Mountain and Greystone areas about the fires Sunday. The area is very lightly populated.
Although he said he was optimistic on Monday, Cartwright admitted that no one could predict what course the fire might take.
"The conditions are extreme right now," Cartwright said. "As everyone in the West is learning, just when you think you have a handle on it, you end up with problems."
Thursday is the estimated date for containment of the fire.
"We've got quite a few resources on it," Cartwright said. "We're hoping we can keep it within 5,000 to 7,000 acres.
On Sunday, a Type II Incident Management Team from North Idaho, which had been fighting the PiRidge Fire northwest of Meeker, was assigned to the fire at Dinosaur National Monument.
Resources on the fire include 198 people, three helicopters, two air tankers, five engines and one water tender.
Dinosaur National Monument remains open to the public, but the following roads have been closed as a result of the fire:
n County Road 16 east from the junction with County Road 161.
n County Road 95 north from the junction with County Road 104.
n County Road 16 north from the junction with Highway 40.
n County Road 14 north from the junction with Highway 40.
Cliff Hutton, unit operations manager at the Craig Interagency Dispatch Center, said people should be cautious with the holiday weekend approaching.
"The nation's fire-fighting resources are already stretched thin," he said. "We have trouble getting the people and equipment we need to put out lightning-caused fires. We sure don't want to see human-caused fires. We appreciate people reporting smoke and fires to us so we can get to them before they become big. It only takes a little breeze with the dry conditions we have."
Craig Interagency Dispatch Center Manager Cathy Hutton said the center encourages people to report locations where they see smoke.
"During the past several days, the public has called in 15 reports of smoke," she said. "We're glad everyone is aware of the fire danger and helping us look for new fires."
People who think they have spotted a wildfire should contact the Dispatch Center at 826-5037.
The wildfire burning in Dinosaur National Monument, coined the Bear Fire, is the only wildfire not contained in Northwest Colorado.
The PiRidge Fire that burned all last week 28 miles northwest of Meeker, was 100 percent contained Sunday. It burned 2,400 acres.