According to the article some of the areas are getting 30 inches of snow and ice!
With drifts easily doubling that, I could see how 20 meters could quickly become near impossible to clear by hand, especially while it's still coming down.
Hardship breeds creativity. Necessity is the mother of invention (except under excessive government intervention, which may be at the root of reservation problems).
Maybe if we could calculate the present day market value of all the land the US government stole from the Native Americans (I've heard we broke nearly every treaty we signed with the Native Americans... to our shame), that could be structural payments to encourage entrepreneurial activity on the reservation