Last month, construction crews managed to slide the first of two new bridges at the Blacks Creek Interchange on Interstate 84 into place. The side-in-place maneuver was designed to minimize impacts to the heavily traveled interstate. Crews constructed most of the new bridge right next to the existing structure. Then, the old bridge is demolished and the replacement structure is slid into place.
"The driving force behind choosing a lateral bridge slide method was our focus on the people we serve and their ability to get where they need to go,” said Patrick Kelly, the ITD project manager overseeing the work. “We were able to keep lanes open during the entire bridge construction process. Once it was ready, we closed the eastbound lanes and pushed the new bridge into place.”
The entire process takes two to three weeks. Normal bridge replacements can take several months. Crews still have some finishing touches to complete on the new bridge. This method has been used before 2014 when the Lardo Bridge on Idaho 55 in McCall was replaced.
The second bridge for the westbound lanes has been constructed next to the old structure. Crews are currently finishing up the eastbound side of the interchange. They will be ready to slide the westbound bridge into place this morning using the same method.