Alternate Routes for I-70 and Eisenhower-Johnson Tunnel Closures
Interstate 70 is a key route to Colorado’s mountains, but winter weather, crashes, and safety closures can lead to major delays or complete shutdowns. Between October 2023 and April 2024, over seven million vehicles passed through the Eisenhower-Johnson Memorial Tunnel, causing hundreds of crashes and over 200 hours of closures.
If I-70 is blocked, there are three main detour options. While they provide alternate routes, they can add significant travel time depending on conditions.
South Route via U.S. 285 (Best Alternative)
This is the most commonly used detour when I-70 is closed. The route takes about three hours from Denver to Vail, adding one to two extra hours compared to normal travel times.
- Westbound: Take U.S. 6 W to C-470 E, then follow U.S. Hwy 285 S to Fairplay, CO 9 N to Frisco, and I-70 W to Vail.
- Eastbound: Take I-70 E to Frisco, then CO 9 S to Fairplay, U.S. Hwy 285 N to C-470 W, and U.S. 6 E to Lincoln Street in Denver.
North Route via U.S. 40 and CO 9
This route is best if the Eisenhower-Johnson tunnels are closed, but I-70 remains open elsewhere. It adds one to one-and-a-half hours without traffic.
- Westbound: Take I-70 W to the Empire Junction with U.S. Hwy 40, then U.S. Hwy 40 W to Kremmling, CO 9 S to Silverthorne, and I-70 W to your destination.
- Eastbound: Take I-70 E to Silverthorne, then CO 9 N to Kremmling, U.S. Hwy 40 E to I-70 E, and continue to Denver.
⚠ Note: This route still requires portions of I-70 and Berthoud Pass (U.S. 40) frequently closes due to snow and avalanches.
Steamboat Springs Route (Avoids I-70 Completely)
This longest detour is only recommended if I-70 is completely shut down for an extended period. It avoids the interstate but takes several extra hours.
- Westbound: Take 287 W from Fort Collins to Ted’s Place, then CO-14 W to U.S. 40 E to Kremmling, CO 9 S to Silverthorne, and I-70 W to the destination.
- Eastbound: Take I-70 E to Silverthorne, then CO 9 N to Kremmling, U.S. 40 W to CO-14 E, and continue to Larimer County.
Travel Tips
- Always check road conditions before heading out, as weather and crashes can change route availability.
- Be prepared for delays, road closures, and extreme winter conditions, especially in high-altitude areas.
- Carry a winter storm kit with essentials like food, water, blankets, and emergency supplies.
While detours can extend travel time, they ensure drivers aren’t stranded when I-70 is shut down.
