Hanging Lake tunnel closed indefinitely

GLENWOOD SPRINGS Motorists traveling Interstate 70 through Glenwood Canyon will find the eastbound bore of the Hanging Lake tunnels closed indefinitely. The Colorado Department of Transportation announced Friday that engineers have found a crack in the bore which had widened to a point where it was not longer safe to drive through.Engineers had been monitoring the crack over the past year and an inspection Friday showed that the crack had recently expanded.”We are taking every precaution to ensure public safety,” said CDOT executive director Russ George in a prepared statement. “We believe the tunnel is stable and don’t anticipate a structural failure, however, we’re going to err on the side of caution and make the necessary repairs to be certain there is no risk to motorists before we reopen the tunnel to traffic.”The westbound bore will be open to one-lane traffic in each direction.The 4,000-foot tunnels, completed in 1992, run between two rock outcrops with a five-story control center in the middle. The center was covered with backfill during construction, and over the years rockfall and debris have added excessive weight. The increasing weight opened an estimated 70-foot-long crack in the structure.CDOT project engineer Joe Elsen said the crack is about 105 feet long in a slab of reinforced concrete. He explained that the crack is in a part of the tunnel next to the five story command center. The center rests in a valley between two rock outcrops through which the tunnels run. The area between the rock outcrops was traversed by a “cut and cover” tunnel which was covered with backfill to blend the building into the natural surroundings.Elsen said the original idea was to repair the crack without closing down the bore. “The crack has changed enough and worsened … [and] the more we talked about it, we decided let’s just close it down,” he said.The actual repair process will be decided on next week, but it will involve removing the overburden and repairing the crack, which could take some time.”We would like to have it done before the first snow flies and hope much sooner than that,” he said.This summer CDOT also plans to repave parts of Interstate 70 on the west end of Glenwood Canyon in May and June. That project will reduce traffic to a single lane in each direction.The tunnel bore closure “will not effect the repaving,” said CDOT spokeswoman Nancy Shanks.The first phase of repaving will involve resurfacing eastbound I-70 from the No Name to Grizzly Creek exits. The work will require rerouting eastbound traffic onto one of the normally westbound lanes. That will result in two-way traffic from the No Name Tunnels to the Hanging Lake Tunnels.”We were going to split to four lanes on the west side of the tunnel originally,” Elsen said. “The plan now [is to] run two lanes [and] two-way [traffic] for another 4,000 feet” through the westbound tunnel bore.