Wood River Valley residents can expect to see post-fire erosion and mudslides for another three to five years, a Burned Area Emergency Response team leader said during a public information meeting Thursday.
“There are no treatments that can be utilized to bring this back to pre-fire stability,” Eric Schroder, a U.S. Forest Service employee, told the small group of people at the Community Campus in Hailey. “You can reduce erosion on a hillside scale, but these cycles of hillside erosion and deposition are pretty much inevitable.”
According to information supplied by the Forest Service, BAER teams normally try to implement erosion-control measures before the first heavy rains following a wildfire. In the case of the Wood River Valley, it’s already too late. Thunderstorms last week initiated mudslides that inundated roads and private property in Croy Creek Canyon and Greenhorn Gulch. In the Baker Creek drainage, Ketchum District Ranger Kurt Nelson said Thursday, “probably thousands of yards of debris have come off the hillside.”
The BAER team, which includes a soil scientist, a fisheries biologist, a roads engineer and a hydrologist, began its assessment work Tuesday, Sept. 3. By Thursday, the team had completed a burned-severity map of the 174-square-mile burned area. Schroder said the map was compiled through satellite imagery and ground assessments.
The map divided the burned area into four categories:
- Unburned: 33,000 acres, or 28 percent.
- Low severity: 17,000 acres, or 15 percent.
- Moderate severity: 57,000 acres, or 49 percent.
- High severity: 9,500 acres, or 8 percent.
Schroder said high-intensity burning occurred in forested areas and moderate burning occurred mostly in areas of sagebrush and bitterbrush. He said that in both areas, ground cover has been almost entirely burned, but the high-severity areas have also lost organic matter in the soil.
“We’re looking at much slower recovery time in those areas,” he said.
He added that due to the loss of groundcover, both high- and moderate-severity areas are very susceptible to erosion.
Schroder said that in the low-intensity areas, grass has already begun to sprout.
According to the map, the largest high-severity areas are:
- On the south side of Greenhorn Gulch, and on both sides in the upper end.
- On the south side of Deer Creek, from Clarendon Hot Springs west to about Narrow Gauge Gulch, a distance of about three miles.
- On the south side of Baker Creek, from Alden Gulch west to the end of the road, a distance of about five miles. The fire burned along most of the Baker Lake trail to the east side of Baker Lake. Nelson said the road will probably be closed for the season, at least past the East Fork.
- On the southeast side of Warm Springs Creek from Barr Gulch west to Rough Creek, a distance of about two miles.
- On the east side of Willow Creek in the Fairfield Ranger District.
Schroder said the BAER team will assess threats to water quality and fisheries as well as the potential for faster spread of noxious weeds.
The BAER team was scheduled to complete its burned-area conditions assessment by Tuesday, Sept. 10, and to submit a report with treatment recommendations to the Intermountain Region office in Ogden, Utah, which is scheduled to review the recommendations and approve a plan by Sept. 16.
“We don’t do a lot of things fast in the Forest Service, but this is one of the things that we do do fairly rapidly,” Schroder said.
In an interview, Fire Information Officer John Calabrese said that if the plan contains recommendations expected to cost more than $500,000, it will also have to be approved by the Forest Service headquarters in Washington, D.C.
Schcroder said that if a plan and funding are approved, a BAER implementation team will be created using mostly Ketchum Ranger District personnel.
According to Forest Service information, BAER teams implement erosion-control measures on national forest land only in areas where there are significant threats to public safety or to property and other valuable resources. Those measures can include removal of debris clogging road drainages, seeding of grass to help re-establish ground cover, construction of temporary channels to direct runoff, improvement of drainage on trails, and the felling of trees and construction of straw wattles to slow runoff.
Schroder said mulch applied from the air can be effective in dispersing the force of raindrops on bare soil.
He said the implementation team will remove or increase the size of culverts under roads and trails threatened by debris flows, and action to clear debris could begin immediately.
“We have a huge problem,” Nelson said regarding debris flow into creeks. “We are going to see a rebalancing of the drainages.”
Schroder said dispersed campsites along Deer Creek and upper Warm Springs Creek have been inundated with mud and may not be reopened for a couple of years.
Nelson said the Ranger District has received calls from people offering to volunteer with trail reconstruction. He said people who want to be put on a list of volunteers to help next summer can call Janelle Conners at the Blaine County Recreation District at 578-2279.
Greg Moore: email@example.com
Public meeting set for Thursday
A public information meeting on the BAER team’s report is scheduled for Thursday, Sept. 12, at 7 p.m. at the Community Campus in Hailey. Fire Information Officer John Calabrese said Monday that the team had completed its fieldwork and was engaged in compiling the data.
Fire restrictions lifted
The U.S. Forest Service announced Sept. 9 that restrictions prohibiting campfires have been lifted for all public lands in Idaho.