It’s known as Avalanche Alley, The 12-mile stretch of Idaho State Highway 21 between Grandjean Junction and Banner Summit and now it has been reopened after being closed as a precaution due to recent snowfall. The Idaho Transportation Department closed the roadway early Friday morning ITD says its forecast team has reduced closures by more than 60 percent since it began forecasting slides and slide threats three years ago. Roughly 45 to 50 slides happen in the area each winter season.