In order to provide safer access for pedestrians and cyclists, the City of Billings planned the installation of a multi-use structure under Main Street, the busiest road in all of Montana. It was imperative that traffic flow over the seven lane road be uninterrupted during construction. In order to save time and money, a two-flange galvanized steel Tunnel Liner Plate solution from Contech was chosen.
During the construction phase, all seven lanes of traffic flowed normally because all of the work was done beneath the roadway. The Tunnel Liner Plate was delivered to the jobsite as unassembled curved plates. These plates were then bolted together and installed, plate by plate, as the tunnel advanced.
Stillwater Excavating of Columbus, Montana, installed 199-ft. of Liner Plate. The structure was 14’ in diameter and wide enough to accommodate a 10’ concrete trail running through it. It also included lighting on both the ceiling and the entrances. In addition, the structure provides extra drainage capacity for the adjacent Alkali Creek during flood events.
“By building this path and tunnel, we’re providing a safer alternative for people to cross Main Street when they’re walking or biking” stated Will Robbins, Project Manager with the City of Billings.
Overall, the project was completed in approximately three months without lane closures or any other traffic disruptions. The structure links the existing trails in three areas of the City and is part of 6.5 miles of new trail construction. A grand opening was held in November 2010 with about a dozen cyclists pedaling through a blue ribbon.
The tunnel was funded by multiple sources, including federal stimulus money and state and federal transportation funds. In addition, other monies were contributed by the Recreational Trails Program through the State Department of Fish, Wildlife and Parks, St. Vincent Healthcare, the Sample Foundation and BikeNet, a local bike advocacy group.