Avalanche-Prone Section Of Idaho 21 Closed
Boise County, Idaho - The 12-mile stretch of Idaho 21 between the Grandjean Junction and Banner Summit closed last night,Tuesday, March 12 at 8 p.m. as an avalanche safety precaution, the Idaho Transportation Department announced. The route will be evaluated for re-opening this afternoon.
The road closure is due to high temperatures and avalanche activity. The avalanche risk is "considerable," according to forecasters. This is the fifth closure of this section of road this avalanche season.
During avalanche season last year, there were eight closures between Nov. 1 and March 31, totaling 21.5 days. A total of 50 slides tumbled down on the highway during that time, as the area saw more than 28 feet of snowfall.
The notorious "Avalanche Alley" section between the Grandjean Junction turnoff and Banner Summit is home to about 60 avalanche chutes and 90 percent of the avalanches in the state that affect highways.