SALT LAKE CITY — Large wildfires that delivered destruction last summer in two distinct watersheds have long been snuffed out, but their lingering effects include a spring runoff that will happen a month earlier, less water in the creeks and heightened risk for damaging mud flows.
A new report spells out the "considerable" potential for more trouble on the ground and in creeks as a result of the Seeley Fire in central Utah and the Clay Springs Fire north of Delta.
"If we were to get a large precipitation event over either one of these watersheds, you can see that there will be mud and debris flows," said Randy Julander, supervisor of the U.S. Natural Resources' Utah Snow Survey. "It is something we should be a little concerned about."
Julander's monthly report detailing February's accumulation of rain and snowfall across the state was released Tuesday and also included an addendum specifically addressing snowpack behavior, runoff and stream flows in regions dramatically impacted by wildfire.
The Seeley Fire, for example, burned 48,000 acres and wiped out 18,500 acres of the Huntington Creek watershed in the bottom portion of the basin. Because of the burn conditions in the watershed, Julander said he expects the typical April to July snow melt period to be moved up by a month — a condition that could persist for years to come.
A heavy rainstorm in August on the fresh burn scar washed away soils no longer held together by root systems, causing damaging mud and debris flows that closed state Route 31 for a week. The heavy sediment in the creek led to fish kills and caused water filtration problems to a nearby power plant, challenges county officials are still grappling with.
Similar conditions are playing out north of Delta as a result of the Clay Springs Fire, which burned 180,000 acres and damaged close to 97 percent of the Oak Creek watershed.
Julander said if the weather behaves as it has been, the north-facing mountains could begin shedding snow by mid-month. Soil moisture levels at one particular site are already "powder dry," he noted.
Snow survey employees conducted a field visit to the Clay Springs Fire area last week to check snow measuring equipment and investigate snowpack conditions.
Julander's report said the majority of the snowpack is already gone from the mountains facing the south, and the area remains highly susceptible to soil erosion.
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