After eruptions and lahars, debris flows represent the greatest hazard originating from volcanoes. In Mount Rainier National Park, recent debris flows and associated floods initiating near glacier termini on large glaciated volcanoes have extensively damaged highways, forests (Figure 1), and National Park infrastructure. A storm in 2006 dropped approximately 18 inches of rain in 36 hours across the Cascade Range and unleashed debris flows from the proglacial areas of six drainages within the park (Figure 2). Infrastructure damage totaled approximately $36 million in Mount Rainier National Park (MORA) alone, with major damage also inflicted on roads adjacent to Mount Hood in Oregon. This event, combined with other similar events in the early 2000s, caused scientists to hypothesize a connection between climate change, concomitant glacier retreat, and debris flows.