The nearly week-old Sheldon Ridge fire in the Columbia River Gorge covered 12,188 acres by Monday, but fire crews reported 70 percent containment.
Fifty fire engines, 772 firefighters, as well as truck and air support, continue to work on the blaze as the risk level for homes and other buildings decreases, Oregon Department of Forestry fire information officer Stan Hinatsu said Monday.
"It was a good night for us last night," he said. "While our acres have grown a little bit, we've been able to contain slop-overs on the fire line."
Further containment in the Mill Creek area near The Dalles has allowed the Wicks water treatment plant to reopen, Hinatsu said.
Workers entered the facility last night to restart the system.
"We felt comfortable enough at the time to say, `All right, get the system back up,'" Hinatsu said.
Currently 620 structures are threatened and eight outbuildings and cabins have been lost, according to Hinatsu.
The voluntary evacuations of Wells Creek Road, Upper Cherry Heights Road, Browns Creek Road and the upper third of Vensel Road remain in place, he said.
Mandatory evacuation was in effect for Mill Creek Road south of the 4500 block. No new locations have been added to the list.
Crews planned to assess the hazard level Monday and fire officials may lift some or all of the recommendations, Hinatsu said.
"Hopefully sometime today or tomorrow we'll be able to lift the evacuation orders," he said. "We want to get folks back into their homes as soon as we can. But we don't want to do it and endanger anybody."
Some of the upper command personnel have been diverted to the Cache Mountain fire near Sisters, Ore., Hinatsu said. Two additional crews may be released to that blaze today as well, he said.
"We're starting to begin the phase of releasing crews," Hinatsu said. "But it's not going to be a massive demobilization. We want to have the resources to deal with anything that comes up."
The reduction in firefighters does not signal that all danger has not passed, Hinatsu said.
Weather plays a major role in fire containment, and officials were expecting 35 mph gusts Monday and higher wind speeds on Tuesday.
"Everybody understands that this fire has the potential to get up and go, especially with the winds expected today and tomorrow," Hinatsu said.
The estimated time of containment for the fire was 6 p.m. Tuesday and the anticipated time of control is 6 p.m. Friday, Aug. 2.
So far this fire season, 306,857 acres in Oregon have been touched by 14 major fires, including the Sheldon Ridge fire that began with a lightning strike seven miles south of Mosier last week.
The situation in Washington has been less grave, though two blazes in the north-central region of the state, covering 38,199 acres, were still burning Monday.
On Sunday, crews battling the larger Deer Point fire 27 miles north of Chelan had achieved 45 percent containment; the Pickens fire five miles north of Tonasket was 80 percent contained.