Debris Avalanche

Mount Hood is an active volcano close to rapidly growing communities, recreation areas, and major transportation routes and therefore imposes heightened risk.

Lahars can be generated by hot volcanic flows that melt snow and ice or by landslides (debris avalanches) from weakened rock forming the steep upper flanks of the volcano.

Mount Hood is Oregon's highest peak and an active volcano of the Cascade Range.

Mount Hood, which has been active for at least 500,000 years, occupies a long-lived focus of volcanic activity that has produced ancestral Hood-like volcanoes for the past 1.5 million years.

Both eruptive and noneruptive processes at Mount Hood generate several types of landslides and water-mobilized flows that sweep the volcano’s flanks and surge down river valleys.