1/3/2007
Idaho 21 closed Wednesday afternoon; ITD crews monitor area's weather and avalanche conditions
GRANDJEAN - Idaho 21 between the Grandjean junction and Banner summit closed Wednesday at about 4 p.m., the Idaho Transportation Department announced.
Transportation department crews are monitoring the section of highway. The closure will remain in effect until conditions are safe for motorists to travel through the area.
On Wednesday afternoon, an inch of snow was falling each hour in the Idaho 21 area and was expected to continue into Thursday. The snow was accompanied by high winds. ITD staff say the snow and winds create cornices, or overhanging ledges, on the upper parts of mountains. When the cornices come loose and fall, they can create avalanches.
Idaho 21 is a regional route between Stanley and the Treasure Valley. The 9-mile section of the highway between the Banner summit and the Grandjean junction, called Canyon Creek, has numerous documented avalanche chutes. Idaho 21 between the Banner summit and the Grandjean junction experiences about 90 percent of the avalanches in the state.
Motorists seeking alternate routes to the area are advised to use Idaho 75 or U.S. 20. From Mountain Home, U.S. 20 heads in a northeast direction and connects with Idaho 75. Idaho 75 then heads north through Bellevue, Hailey, Ketchum and the Sun Valley area. From Twin Falls, motorists can take U.S. 93 to the north. U.S. 93 turns into Idaho 75 and heads north through the same communities.
During the winter months, the ITD advises motorists to monitor road conditions by visiting 511.idaho.gov or calling 511.
Transportation department crews are monitoring the section of highway. The closure will remain in effect until conditions are safe for motorists to travel through the area.
On Wednesday afternoon, an inch of snow was falling each hour in the Idaho 21 area and was expected to continue into Thursday. The snow was accompanied by high winds. ITD staff say the snow and winds create cornices, or overhanging ledges, on the upper parts of mountains. When the cornices come loose and fall, they can create avalanches.
Idaho 21 is a regional route between Stanley and the Treasure Valley. The 9-mile section of the highway between the Banner summit and the Grandjean junction, called Canyon Creek, has numerous documented avalanche chutes. Idaho 21 between the Banner summit and the Grandjean junction experiences about 90 percent of the avalanches in the state.
Motorists seeking alternate routes to the area are advised to use Idaho 75 or U.S. 20. From Mountain Home, U.S. 20 heads in a northeast direction and connects with Idaho 75. Idaho 75 then heads north through Bellevue, Hailey, Ketchum and the Sun Valley area. From Twin Falls, motorists can take U.S. 93 to the north. U.S. 93 turns into Idaho 75 and heads north through the same communities.
During the winter months, the ITD advises motorists to monitor road conditions by visiting 511.idaho.gov or calling 511.