MONTANA DEPARTMENT OF TRANSPORTATION
BIG SKY – Some locals remember traveling on newly constructed roads and bridges to attend Big Sky Resort’s opening day in 1973. Critical infrastructure has not only faithfully carried skiers year after year to their destination, it has also withstood heavy equipment as Big Sky grew. Now, nearly 50 years later, drivers once again can enjoy traveling over smooth bridges. The Montana Department of Transportation’s Big Sky Bridge Decks project completed work today on three bridges in the Big Sky area.
“MDT thanks everyone for their patience and understanding during this busy construction season,” said William Fogarty, Butte District Administrator for the Montana Department of Transportation. “These bridges sorely needed these improvements and had not experienced repairs of this scale since they were originally built, when Big Sky was a fraction of the size it is today. These bridges will serve the community for many more years to come.”
Dick Anderson Construction crews began work in late May with repairs to the bridge by the intersection of MT 64 and U.S. 191. They also started work on the bridge by Little Coyote Road. That structure had a longer construction schedule as it was a full reconstruction of the bridge deck. The Little Coyote Road crews had to rebuild the bridge deck from the bottom layers up. Once the bridge by MT Route 64 and US 191 was complete, crews worked on a bridge on U.S. 191, two miles north of the turn to Big Sky.
Repairs were focused on the bridge deck, the surface of a bridge vehicles drive on. A bridge deck is comprised of multiple layers. These begin with a strong base layer that lays on top of supportive beams, include a layer of rebar that reinforces the structure, and finish with a concrete surface. Over time, water seeps into small cracks on and near the bridge, eventually creating larger potholes and cracks. Patches are then used to fill in holes as a quick repair to ensure that deterioration does not continue. However, damage can permeate multiple layers of the deck or patches can become so numerous that large-scale repairs are needed.