Bend smoke from 13,000-acre prescribed burn near Chemult

(Update: Smoke blows into Bend from large prescribed burn; air quality improves; small fire stopped near Tumalo Creek)

The smoke that swirled into the Bend area Saturday morning, prompting concern from many residents and worsened air quality, is coming from a 13,000-acre prescribed burn begun Friday about 10 miles southwest of Chemult, a U.S. Forest Service official said.

Earlier, dispatchers said they believed it was from burnout work on the approximately 30-acre Ikt Butte Fire south of Bend surrounded by lava flows.

But Forest Service spokesman Kassidy Kern noted that the Boundary prescribed burn began Friday on the Chemult Ranger District of the Fremont-Winema National Forest, using aerial ignitions on up to 13,000 acres over a 2- to 4-day period.

” The primary objective of the prescribed burn is to safely reduce the buildup of dead/down and live surface fuel to a historic fire-adapted ecosystem, ” according to a Forest Service release on the South Central Oregon Fire Management Partnership Facebook page. ” The area also will be less susceptible to severe impacts if a wildfire occurs in the future. ”

The treatment area begins about four miles west of the Diamond Lake Junction of U.S. Highway 97 and state Highway 138, extending seven miles south of Highway 138 to the junction of Fores Service Road 70 and the forest boundary, and from the forest’s western boundary, bordering Crater Lake National Park.

The SCOFMP reported Saturday morning that all lines held through the evening and smoke had impacted highways 138 and 97 south of Diamond Lake Junction to the Silver Lake Highway.

About 2,000 acres of the project were burned Friday, and officials said the burn operations would continue ” as long as weather remains favorable. ”

Bend’s air quality reading moved into the ” unhealthy for sensitive groups ” category Saturday morning, the worst in the state, according to the state Department of Environmental Quality’s Air Quality Index map. It was down to the ” moderate ” category by mid-afternoon.

Prineville had been in the ” moderate ” category earlier Saturday morning, but improved to ” good. ”

Kern said the weather forecast is favorable for clearing the smoke out of the area through the weekend, improving air quality for the next 24-48 hours.

Meanwhile, the risk of human-caused fires remains high heading toward autumn. Crews on Saturday tackled Incident 982, an abandoned campfire near Tumalo Creek that was lined and contained at 1/10 of an acre, Kern said.

The lightning-sparked Ikt Butte Fire south of Bend is burning in a kipuka — a 33-acre island of forested land, surrounded by a lava flow — on the Newberry National Volcanic Monument in the Deschutes National Forest.

A representative of the Central Oregon Interagency Dispatch Center in Redmond said the fire has been ” black-lined ” by crews, and they are letting the interior burn out. It has consumed about 29 of the 34 acres, he added.

The Ikt Butte fire was reported just over a week ago, about six miles southeast of Lava River Cave. Officials said at the time it was one of two small fires on the forest being monitored “to meet ecological objectives,” the other being in the Mt. Washington Wilderness.

Officials said crews would suppress the fire if it becomes necessary.