Avalanche threat leads to 3-day closure of Idaho 21 segment
Although snowfall has been scarce in most Idaho locations this winter, enough snow has fallen in the central mountains to warrant intermittent highway closures.
The section of Idaho21 between Grand Jean Junction and Banner Summit, lived up to its nickname “Avalanche Alley” last month when snow, trees and debris rumbled down some of nearly 60 chutes that meet the highway.
ITD closed a 12-mile segment of the highway as a precautionary measure late in the afternoon on Dec. 28 and reopened it nearly three days later, on Saturday, Dec. 31. Snow fields in the rugged canyon were unstable and threatened to send debris onto the highway.