One hazard looming above Davis County will become a sure thing as the hot, dry summer season arrives: There will be brush fires in the foothills.
They happen every summer, sometimes sparked by lightning but more often through human carelessness or, worse still, arson.Since the hazard has a 100 percent certainty rate, the next logical step is to mitigate the effects, members of the county and state Soil Conservation Service said recently, unveiling an ambitious new proposal.
SCS geologist Bob Rasely plans to map and evaluate all of the alluvial fans flowing out of the canyons and streambed cuts in the Wasatch Front foothills in Weber and Davis counties.
By analyzing the sediment and evaluating the drainages above the canyons, Rasely said he can estimate the mudslide potential that would result if a brush fire were to burn off the vegetation above the canyon.
By storing that information on a computer disk and giving it to county planners, a mitigation plan can be put into effect within hours after a brush fire instead of waiting for days or weeks, Rasely said.
And that can be critical because as sure as there will be brush fires, it's just as sure there will be summer thunderstorms, Rasely said.
The quick response plan has another positive point, Rasely said. If the hazard evaluation comes from an SCS source, there may be federal funds available from the agency to help pay for mitigation work such as planting ground cover grasses and building flood control devices.
Rasely said a preliminary survey has identified 90 alluvial fans spreading out from the foothills in the two counties, not counting the Weber and Ogden river systems, which he is excluding.
Each one is different, he said, with different sediment flow potential and canyon configurations that will affect the potential for a mudslide or debris flow after a fire.
Rasely said he's concentrating on the foothill areas, where homes have been built in what he calls the "urban/forest interface areas." Help has been promised by the U.S. Forest Service, which administers most of the land above the cities.
The Davis commissioners were intrigued by the idea.
"It sure makes a lot of sense to have that done in advance," said Commission Chairman Gayle Steven-son.
Commissioner J. Dell Holbrook urged Rasely to begin his evaluation and mitigation program above Centerville, where a grass fire late last summer burned off about seven acres in a steep area.