Las Vegas CBS KXNT – Just like wildfire, heavy rains are inevitable in the Spring Mountains. Even without fire, the drenching rains of monsoon season often cause flooding in southern Nevada. Burned soils of the Carpenter 1 fire should increase flooding for two reasons. First, severely burned dirt becomes “hydrophobic.” It gets a glasslike sheen and sheds water rather than absorbing it. Second, the physical effect of fire tends to remove vegetation that holds soil in place, and even loosens rocks and boulders on slopes as the soil bakes.
In this area, flooding after a fire tends to bring black and muddy water rushing downstream. Ash floats upon water until it soaks through. Vast quantities of ash may sweep off hillsides and come to rest several feet deep in creek bottoms where deposited by moving water. Soot and ash from the Carpenter 1 wildfire is expected to wash down from Kyle Canyon with this weekend’s rain, creating a dangerous mess on the roads in the city’s northwest flood plain.
Grand Teton Drive, Farm Road, and Tenaya Way were inundated with debris and ash last weekend flowing down from the Mount Charleston fire area. The city is expecting similar conditions this weekend, with rain in the forecast for the next five days.
“That soot, when it’s wet, is like driving over glass or ice,” Las Vegas City Councilman Steve Ross told KXNT, “and when it’s dry, you’re in a puff cloud, so it’s dangerous either way.”
The city will post flood conditions on twitter at #LVroads.
The most hazardous roads are Grand Teton Drive from North Durango all the way to Rainbow, and the intersections on Shady Pines Street.