LOWMAN,Idaho -- Alarge avalanche has blocked part of Idaho State Highway 21 about 27 miles north of Lowman. The area is known as Avalanche Alley.
The slide happened two miles beyond the Canyon Creek Bridge, just past Grandjean Road, according to the Idaho Transportation Department.
The roadway was closed to traffic at the time.
An ITD avalanche forecaster discovered the slide around 3 p.m. Thursday while on patrol. The debris pile, up to 50-feet deep, includes broken trees, bushes, and rocks, as well as about five feet of standing water covering the road.
Spokesperson Reed Hollinshead said the avalanche came down a slide path not yet documented by ITD.
The unique thing about this one is there are 53 known avalanche chutes - paths that we've seen avalanches come down before - and this is a new one, Hollinshead said.
ITD says the area is too unstable to get in and attempt any clean-up so crews will have to reassess Monday morning.
Vehicles are required to take an alternate route by driving US Highway 20 to State Highway 75 in order to bypass the closed section.
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