Concerns rise about flooding, debris flows in Lake Christine Fire burn scar

The forest on Basalt Mountain shed water rather than absorbed it during runoff this spring. The resulting erosion washed out a portion of Basalt Mountain Road below the Mill Creek Trail.
Scott Thompson/courtesy photo

As the temperatures climb and runoff from the snowpack increases, the threat of flooding and debris flows also is on the rise.

Local emergency managers are particularly concerned about flood and flow risks from the Lake Christine Fire burn scar. They will host a meeting at 6 p.m. tonight at the Eagle County office building next to Crown Mountain Park to discuss the risks in those specific areas. The meeting will feature officials from Roaring Fork Fire Rescue, the town of Basalt and the emergency management offices of Pitkin and Eagle counties.

The fire scar creates special concerns.

“Wildfires result in a loss of vegetation and leave the ground charred and unable to absorb water,” said a statement from a consortium of emergency management agencies in the Roaring Fork Valley. “This creates conditions for flooding. Even areas that are not traditionally flood-prone are at risk of flooding for up to several years after a wildfire.”

Roaring Fork Fire Rescue Chief Scott Thompson recently traveled up Basalt Mountain Road and reported that conditions match what fire experts with the U.S. Forest Service anticipated. The soils that experienced the greatest burn severity are shedding the water rather than absorbing it, Thompson said. Water was flowing off hillsides in sheets and eroding the road between the main parking lot and the Mill Creek Trailhead, he said.

The worst-case scenario would be a rapid rise in temperatures for an extended time with periods of heavy precipitation. The best-case scenario is continued slow runoff, with cloud cover and lower temperatures.

Officials are urging residents near the Lake Christine Fire burn scar to register for Pitkin Alert, regardless of what county they live in. When the National Weather Service issues a flash flood warning for the burn scar areas, Pitkin Alert will send out notifications to users who have registered for weather alerts at http://www.pitkinalert.org. Registered users of EC Alert also will receive notifications.

Thompson said there was good utilization by midvalley residents of the alert systems last summer during the fire. The number of people signed up has slipped since then, he said. He wants them to re-engage for their own safety.

A map of the burn scar and areas most susceptible to flooding and debris flows is available at http://www.carbondalefire.org/2019/05/07/lcf_map.

Some steps already have been taken to ease runoff concerns from portions of the burn scar. Colorado Parks and Wildlife used heavy machinery last fall to reseed about 450 acres of the Basalt State Wildlife Area, where the fire tore through in the opening days. Another 625 acres was reseeded in the hills above El Jebel and Basalt this spring. Hand seeding will target areas that were inaccessible by tractor and airplane.

CPW also built check dams and catch basins on its property to slow runoff.

In addition, the town of Basalt, Eagle County, Natural Resources Conservation Service and CPW are teaming on $1.3 million worth of flood control projects. However, much of that work won’t be completed until after this runoff season.

via:: Post Independent