Forest Service: Severely burned areas at special risk for flooding

       With chances of rain in the forecast for the next week and a half, the U.S. Forest Service (USFS) is keeping a close watch not only on the sky but where the precipitation lands.

A U.S. Forest Service map shows the watersheds affected by the Waldo Canyon Fire. Most vulnerable on the Westside to flash floods from severely burned areas are Fountain and Douglas creeks.
Courtesy of U.S. Forest Service

       A cloudburst over any of the 3,375 acres of “high severity” areas resulting from the 18,247-acre Waldo Canyon Fire could lead to flash flooding, USFS spokesperson Rob Deyerberg said in an interview this week.
       Such a situation is because such heavily burned areas absorb less water; that, combined with the loss of vegetation means that in a big rain more water cascades downhill - and also at a faster-than-normal pace, fire officials have explained.
       For Westsiders, the main waterways affected by the fire are Fountain Creek (out of Ute Pass) and Douglas Creek (drainage from the Mountain Shadows and Peregrine burn areas).
       Deyerberg estimated that in the event of a downpour in a severe Waldo fire area, high waters would probably arrive in urban areas in 15 to 45 minutes.
       Anyone caught in such a situation is advised to seek higher ground, where possible, rather than to try to outrun the flow, public safety officials have instructed.
       A related flooding concern is that, if rain continues to fall in coming days, the ground in general will become saturated, so that regular runoff will add to that from the burn areas, Deyerberg said.
       The Waldo fire, which moved northeast after threatening the Westside in its early stages in late June, continues to smolder in the area of Blodgett Peak, near the southwestern boundary of the Air Force Academy. About 20 firefighters remain on duty.
       Another part of the rain-related concern is lightning strikes, which could spark a new fire, Deyerberg said. According to USFS computerized data, there were nearly 10,000 strikes “in the vicinity” in just one day (July 30).

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