GoI70

In October 2011, the Colorado Transportation Commission approved $60 million in funding for this project.  According to CDOT, the Twin Tunnel project proposes to immediately address safety issues and improve traffic flow at the Twin Tunnels east of Idaho Springs, one of the most critical congestion bottlenecks on the I-70 Mountain Corridor.  This project would build a third lane on eastbound I-70, beginning west of the Twin Tunnels and continue east to the base of Floyd Hill, where eastbound I-70 currently becomes three lanes.

This option includes flattening the curve on eastbound I-70, just east of the Twin Tunnels, enhancing safety and allowing for increased speed through this section. The project does not include westbound Twin Tunnel or westbound I-70 improvements. Furthermore, this project does not violate the long-term solution for the I-70 Mountain Corridor as outlined in the I-70 Mountain Corridor Final Programmatic Environmental Impact Statement (PEIS.)  During construction, traffic will be rerouted around the Twin Tunnels and placed on an improved frontage road.

Implementation Timeline:    The Federal Highway Administration (FHWA) must still approve the project, and is expected to issue a decision by the fall of 2012. If the project receives the federally required approvals, construction would begin in the spring of 2013, and be open to traffic by the end of 2013.

Weekend Travel Forecast:

Here is what history has shown us for this mid-February weekend traffic:

 Westbound to the Mountains

On this Saturday in previous years, traffic delays started at 6:30 a.m. and peaked around 9:00 a.m. with 30 minute delays.  There were delays of under 10 minutes by 10:30 a.m.    The Sunday historic data shows delays of only 20 minutes between 6:00 and 8:30 a.m.

Eastbound to Front Range

The previous years’ Saturday patterns show a build-up at Noon, a peak at 5:00 and diminishing traffic at 6:00 p.m.  Historic data on this Sunday in previous years shows an earlier peak travel time.  Traffic started to build closer to 1:00, peaked between 3:00 and 4:00, and dropped off right around 6:00 p.m.

REMEMBER, it is very possible that CDOT will put either speed harmonization or metering into effect EB on Sunday.  Speed harmonization could start as early as 11:00 a.m. in Silverthorne, and traffic would follow a pace car at a controlled speed to Empire.  Metering means up to 20 minute traffic stops at the tunnel. Metering can sometimes cause the delays to continue past the usual 6:00 p.m. timeframe. 

Check GoI70.com/mobile before you jump on the road to see if CDOT has put these practices into play, and to learn what the traffic is like at that moment.

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