HAMILTON - When wildfire burns its way through a forest, it's often the immediate and obvious effects that get the most attention: Smoke in the air and homes threatened by flames are at the fore of most people's concerns.

But for forest managers and landowners, fire's impacts on the soil, wildlife, water and other resources can be just as important.

In mid-October, the U.S. Forest Service conducted a Burned Area Emergency Response assessment on the after-effects of the Kootenai Creek fire.

On Monday, they released a report detailing the burn's effects on watersheds.

"It's all based on the extent of the fire and its severity, how much of the area burned at high intensity and where those spots are located," said Bitterroot National Forest hydrologist Ed Snook.

The responses include an initial flush of ash, overland flow and associated erosion on steep slopes, flash floods during rain, and debris flows and an increase in snowmelt water yield due to changes in evapotranspiration.

According to the report, the Brooks Face watershed, which drains to the east between Stevensville and Florence, was hit the hardest, with about 41 percent of the area burning with moderate or high severity.

That area had about 1,120 total burned acres with 560 acres burning at moderate or high severity.

"There are ranches right at the base of that slope and the effects tend to carry as long as you have slope to push it downhill," Snook said. "They may see some localized erosion and some tongues of sediment and ash deposit on the ranch roads and in their headgate areas."

Snook said the Forest Service will contact landowners to tell them what to expect.

The Kootenai-Larson Creek watershed, which held the bulk of the fire, only saw a moderate to high-severity burn on about 13 percent of total acres burned.

In that watershed, 5,388 total acres burned with about 2,694 acres burning at moderate to high severity.

According to the report, the probable watershed responses in those areas could put some manmade resources at risk, including forest road crossings in upper Larson Creek, foot and horse trails in Kootenai Creek Canyon and ranch roads or headgates below Brooks Face.

The report estimates it will take three to five years for vegetation to recover.

The burn is not expected to affect residences in the Kootenai Creek valley bottom because the main fire area within Kootenai Creek Canyon is far enough from homes that debris or flash flooding would dissipate in the several miles of channels before approaching homes.

Residents should avoid crossing flooded ranch roads and be aware they may be stranded in some locations for short periods.

The report's recommendations include cleaning culvert outlets on Forest Road 740 in upper Larson Creek, repairing damaged drainage structures and tread on trails before the next projected damaging storm, and notifying landowners about possible high flows and increased ash and sediment deposit.

Snook said that from an ecological standpoint, the burn presented little out of the ordinary.

"The fire was well within the realms of a natural event," he said. "And despite the fact that so many people were inconvenienced by the smoke, it's really not a bad thing. It's a good thing for the environment for it to burn in pieces like that."

The lightning-caused fire began in July and burned a total of about 6,700 acres.