Ice dam

An ice dam (or ice barrier) occurs when water collects due to a blockage or plug produced by ice. Ice dams can occur for a variety of reasons: caused by a glacier, over a river, on the roofs of houses.

An ice dam is formed when a glacier, or an ice sheet, causes a stagnation of the melting waters or natural drainage to form an ice lake.

A small-scale ice dam is a problem in maintaining homes in cold climate areas. This is an ice ridge that forms on the roof that does not allow water to drain from the accumulations of snow on the roof.

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