A report issued by the U.S. Forest Service for a prescribed fire that escaped on the Dakota Prairie National Grasslands in northern South Dakota last year cited weather as being one of the primary factors in losing control of the fire.
The Pasture 3B prescribed fire was planned at 210 acres, but strong winds on April 3, 2013 caused by the predicted passage of a cold front pushed the fire across a mowed fire line into tall grass and ultimately burned 10,679 acres, (3,519 acres federal and 7,160 acres private). The wildfire, named Pautre Fire, was stopped at 11 p.m. that night.
On April 3, 2013 we wrote about the wildfire:
An article in The Rapid City Journal has more information about the impacts of the fire on the ranchers. Privately owned grazing, hay stacks, and miles of fencing were damaged or destroyed during the ranchers’ calving season. Here is an excerpt:
“Laurie Casper, 36, said the fire destroyed 95 percent of her family’s farmland, which is more than 1,000 acres.
‘We lost all of our calving pasture, we lost our summer grazing, we lost our fall grazing, we lost 100 percent of our alfalfa— which we cut for hay bales in order to feed the cattle this oncoming winter— all that’s completely gone,’ she said. ‘And there’s just just miles and miles of fences that are completely gone.’ “
The prescription in the project’s burn plan for the maximum wind speed at eye level was 15 mph and the maximum wind speed at the 20-foot level was 20 mph. One of the spot weather forecasts for the morning of the prescribed fire predicted the passage of the cold front, with winds shifting from the south at 5 to 11 mph in the morning, to northwest at 25 mph with gusts to 30 mph in the afternoon. The actual weather that day was very similar to the forecast.
About a month later, another prescribed fire not too far away, at Devils Tower National Memorial in western Wyoming, also escaped, due partially to strong winds. That report still has not been posted on the Wildland Fire Lessons Learned Center website. We were told today that was due to a glitch, and it will appear there very soon, possibly as early as today, February 4. (UPDATE, February 5, 2014: the National Park Service arranged to have the Devils Tower report posted late in the day on February 4. We wrote about it here.)
Pautre Fire. US Forest Service photo.
The report said firefighters concluded they would not do much different next time (page 12):
Firefighters did an excellent job of planning, organizing and executing this prescribed fire and adhering to the prescribed fire plan. Following the control of the escaped fire some firefighters had difficulty thinking of anything they would do differently next time. While it is true that we work in a dangerous environment with unexpected changes in weather, we strive to be a learning culture and continuously improve our ability to make decisions that evaluate risk and get work done on the ground.
Some of the issues listed by the Facilitated Learning Analysis team included:
- Improved weather forecasts are needed.
- Consider additional research on methods to predict effects of drought on fire behavior in grass fuel models.
- The nearest remote automated weather station (RAWS) is more than 90 miles away.
- The project was conducted at the critical edge of the prescription.
- Consider gaming out worst case scenario “what ifs” during the planning process, and discuss with participants during the on-site briefing.
- There were problems with radio communications [note from Bill: I don't remember EVER seeing a report like this that did not cite radio communications as being an issue].
The commendations section included this:
The personnel involved in all levels of the Pasture 3B prescribed fire were motivated, worked well as a team, were adequately trained, and appropriately briefed. They had a keen awareness that this was the first burn of the year, and took numerous precautions to ensure successful completion of the prescribed fire.
We did not see any mention in the report of damaged fences, hay, or pastures.
Some ranchers in western North Dakota donated hay to the South Dakota ranchers who lost theirs in the escaped prescribed fire.