Glacier Peak's attractions, as well as its hazards, thus tend to be overlooked. Yet like most other Cascade volcanoes, Glacier Peak has erupted several times since the Iceage glaciers retreated 15,000 years agomost recently around the eighteenth century. Since glacial times Glacier Peak has had larger and more explosive eruptions than any Washington volcano except Mount St. Helens. If similar eruptions took place today, they could place nearby communities at serious risk. This report describes hazards that would accompany future activity at Glacier Peak and shows areas that would most likely be affected.
Lahars represent the greatest hazard, followed by tephra fall.