Wildfire increases risk of flooding in some areas

Oct. 01--ARDENVOIR -- Some homes and people, including the community of Ardenvoir, may be at risk from debris flows or flooding after the Cougar Creek Fire.

The U.S Forest Service conducted a burned soil assessment for the Cougar Creek Fire and found the fire burned primarily within the Mad River watershed, according to a Post-Fire Burned Area Emergency Response Assessment released last week.

A Burned Area Emergency Response Assessment, or BAER Assessment, is a study the U.S. Forest Service conducts of the ability of burned soils to hold water after a wildfire, said Holly Krake, an Okanogan-Wenatchee National Forest public affairs officer. If soils cannot hold water it can cause erosion and debris flows.

Within the Mad River watershed 30 percent of the soil burned at a high severity and 30 percent burned at moderate severity.

* The BAER report reached several conclusions about the Mad River watershed, including:

* The area will see a flush of ash, erosion in drainages and steep slopes, flash floods, increased water and debris flows, according to the assessment.

* Runoff may increase twofold. Pine Flat Campground and downstream private residences are at risk from the increased flows.

* The Potato and Windy creeks areas are of particular concern. Hyper-concentrated flows could also be seen in the Potato Creek, Decker Canyon and Gray Canyon areas.

The community of Ardenvoir has experienced flooding in the past out of the Mad River drainage, said Mike Cushman, Cascadia Conservation District director. Residents should be aware that a large weather event could trigger erosion or debris flows.

"Depending on the type of weather event that we may or may not receive there is a heightened potential of flooding or debris flows, post wildfire, Cushman said.

Cushman wants to remind residents to keep an eye out for large weather events, have emergency plans -- including escape routes -- in place and buy flood insurance, he said. People may also be eligible for a post-fire insurance plan that they should look into.

"You need to be aware and it is dependent on the impact of weather," Cushman said. "But there is evidence of those debris flows in the Entiat River."

Overall, though, the Forest Service had positive news from the BAER Assessment, according to an Okanogan-Wenatchee National Forest news release. Only 2 percent of the total soils in the Cougar Creek Fire burned at high severity and 33 percent at moderate severity, according to the assessment.

The Burned Area Emergency Response team reported that plant roots and soils appear to still be able to hold water and are near normal levels for the vast majority of the land, according to an Okanogan-Wenatchee news release.

But even moderate severity fires can cause some erosion and debris flows, according to the assessment.

The Forest Service plans to do some trail and road work, such as adding drainages, in response to the fire, Forest Service Spokeswoman Carly Reed said.

Reach Tony Buhr at 509-664-7123 or (javascript required to see email).

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