In August of 2020, the Grizzly Creek fire burned more than 30,000 acres around Interstate 70 in Colorado's Glenwood Canyon. The following summer, several rainstorms swept across the area and sent devastating debris flows, fast-moving torrents of mud, rocks, and water coursing across the highway. The road was closed for weeks, causing an estimated economic cost to the national economy of about $1,000,000 every hour.