Twin Tunnel on EB I-70 reopens after 9 months of construction
IDAHO SPRINGS, Colo. — Good news for motorists heading out of the Colorado mountains: The newly widened eastbound I-70 tunnel near Idaho Springs opened all three of its lanes on Friday.
The construction of the $106 million Twin Tunnels took nine months. On Monday at 5 a.m., crews began to switch traffic from the detour that has been in place throughout the project to the final configuration through the tunnel. To complete the realignment, crews worked around the clock in order to open the lanes within 72 hours.
While crews worked to get the lanes reconfigured, eastbound I-70 was reduced to one lane. For a portion of the traffic switch, one lane of eastbound I-70 was open on the existing detour route and eventually moved to its final alignment through the tunnel.
All major construction is now complete on this project, and it was celebrated at a ceremony held on Dec. 7.
“How many of you have been in a tunnel this big?” Gov. John Hickenlooper asked a invitation-only crowd inside the tunnel. “I never have… I can’t think of one anywhere that’s quite this, I mean, we should have brought a rock and roll band up here.”
The tunnel, now three lanes wide instead of two, could reduce I-70 congestion, which has become notoriously busy on ski weekends. CDOT estimates the extra lane could cut 10 minutes off a Sunday afternoon commute and reduce crashes in the area by up to a third.
“We deserve this, the state deserves this, the tunnel is exceptional,” said Creek Creek County Commissioner Tim Mauck.
“The pain that we’ve had a little bit through our city of Idaho Springs is well worth the gain and return that we’re going to get from it,” said Idaho Springs Mayor Mike Hillman. “It’s a great project.”
Construction, which included 75 rock blasts, began in April. A frontage road has served as a detour for motorists. That detour could resurface next year if the westbound tunnel is widened, as Hickenlooper would like.
“While this project results in safety improvements and provides travel savings, it still does not solve the I-70 congestion problem,” Hickenlooper said. “It is a stepping stone towards that.”