By Robbie Webber
The 2012 Waldo Canyon and High Park wildfires—two of the most destructive fires in Colorado history—are costing CDOT millions of dollars as fire-scarred hillsides slide down onto major highways and floods cause washouts. Although the problems began last year, dramatic footage showing cars caught up in a mud and debris flow on U.S. Highway 24 went viral last month.
The burned areas not only have little vegetation to hold the soil in place, but the heat of the fires baked the soil, making it even less able to absorb water from summer rains. Key highways, such as Highway 24 between Colorado Springs and Manitou Spring and Highway 14 west of Fort Collins, are expected to experience problems for 3-5 years.
Culverts that previously handled flows are clogging with debris and contributing to flash flooding. “Where there were 2- to 3-foot flows in drainage areas before the High Park Fire, there are now 20-foot-wide slide zones filled with whatever the rain washes down—mud, rocks, muck and debris,” said CDOT Communication Manager Ashley Mohr.
CDOT plans to replace the current culverts with larger ones in many locations. These larger pipes also will diminish the chances that the roadway will be washed out by mud-choked flows that can be much more destructive than water alone.
Because of eroded shoulders and the danger of flooding, CDOT has even closed some popular turnouts where motorists could stop for hiking, fishing, and kayaking.
Earlier this year, representatives from county, state, and federal organizations laid out the dangers to public infrastructure below the Waldo Canyon burn scar. Along with the possibility of losing houses, commercial developments, water, and other utilities, they indicated that an inch of rain could result in highway closures for a few days or weeks, but a major storm could wipe out entire sections of Highway 24.
Robbie Webber is a Senior Associate at SSTI.
By Robbie Webber