Last Summer, the Grizzly Greek Fire (which many of us remember acutely) burned in White River National Forest, including the steep walls of Glenwood Canyon, adjacent to I-70. Unfortunately, this has recently translated into dangerous flash flooding and widely disruptive mudslides. These impacts began around the last week of June, and as a result of the size of the burn scar and the terrain of the canyon, mudslides are very likely to wash debris onto the roadway, and total mitigation of this is nearly impossible. CDOT has worked closely with neighboring states to encourage cross-country travelers to select a more reliable route and avoid I-70 all together. “We’re continuing to work with Kansas, Utah, and Wyoming on diverting folks to I-80. We’re warning those states and their customers that people should expect there to be closures on I-70, if they choose to travel it,” said CDOT Region 3, Communications Director, Elise Thatcher, in a statement.
There were five mudslide events over the 4th of July weekend, and there have even been several closures already in the week following it. “There’s unfortunately a lot of soil on those hills that can still move. We can’t really let our guard down this Summer because there’s still quite a bit of soil and sediment that can be recruited to move around the debris flows,” said Francis Rengers, a research geologist with the US Geological Survey. “If we get more than about .3 inches of rainfall in 15 minutes, or more than a half inch in 30 minutes, we have a chance for debris flow. Those are pretty common rainfall events.” CDOT is working closely with NOAA to predict when rainfall will happen, but that isn’t always accurate. This situation is the new normal – for now – as according to Rengers, it will likely take several Summers before there is enough regrowth to hold the soil on the canyonsides in place once again (though this season is expected to be the worst).
Travelers on I-70 this Summer should be prepared for frequent closures at Glenwood Canyon. “While rain events are difficult to predict, it’s not worth losing your patience over because closing the highway could be a lifesaving thing,” added Rengers. For cross-country travelers, CDOT urges avoiding Colorado’s interstate and taking Wyoming’s I-80 instead. For travelers within Colorado, CDOT suggests drivers either wait out the closure at another exit or rest area, or take the roughly two-and-a-half-hour detour through Craig and Steamboat Springs. To do this, Westbound travelers will need to exit at Silverthorne and travel CO-9 to US-40, then head west to Craig and join CO-13 south back to I-70 at Rifle. Eastbound travelers will need to exit at Rifle and travel the reverse route, CO-13 to US-40 to CO-9 and back to I-70 at Silverthorne. Drivers using other routes – such backroads and mountain passes – should know NOT TO RELY ON smartphone map apps, as they these routes most often do not have phone service, and leave drivers without adequate navigational directions. If you do choose these routes, please be prepared for unexpected stops, and bring water, snacks, flashlights, blankets and a MAP. Sign up for travel alerts here, and frequently check Cotrip.org to know before you go. Safe travels!