Volcanic eruptions are most likely to occur in the Pacific Rim states, which include Oregon. The primary danger area around a volcano covers an approximately 20-mile radius, although there is some danger to people within 100 miles or more. Airborne ash from a volcano can affect people hundreds of miles away from the eruption. The most common volcano-related hazards are ash (tephra), lahars (volcanic mud flows), lava and debris flows, avalanches, and pyroclastic flows.These data depict areas where volcanic hazards may occur during or after volcanic activity. Volcanoes can produce volcanic ash, mudflows, debris flows, avalanches of hot volcanic material, lava flows, and landslides. Residents and visitors to these areas should have an evacuation plan ready should volcanic activity begin.

DOGAMI used data from the U.S. Geological Survey (USGS) Cascades Volcano Observatory (CVO) for this web application. CVO maintains proximal and distal hazard zone data for five volcanic areas in the Western Cascades of Oregon. These areas include Mount Hood, Crater Lake, Newberry, Mount Jefferson, and the Three Sisters. HazVu shows these data as two hazard zones: the high hazard zone (proximal zone) and moderate hazard zone (distal zone). Any person or structure located within these hazard zones should have an evacuation plan ready should volcanic activity begin.

More information: USGS Cascades Volcano Observatory or DOGAMI/Mount Hood Risk Study