Avalanche dams (anti-avalanche dams, avalanche protection dams) are a type of avalanche control structures used for protection of inhabited areas, roads, power lines, etc., from avalanches. The two major types are deflection and catchment dams.
Both types of avalanche dams are usually placed in the run-out zone of the avalanche and in the flatter parts of the avalanche path. In other parts of the avalanche they are ineffective because they may be easily overrun or overfilled.