MDT to Replace Sportsman’s Bridge

By Beacon Staff

BIGFORK – Anyone who’s driven state Highway 82 between Bigfork and Kalispell is likely familiar with Sportsman’s Bridge, a narrow passage over the Flathead River that often elicits brake lights and tight grips on steering wheels.

Staff members from the Montana Department of Transportation acknowledged this experience at a July 14 informational meeting in Bigfork, during which they discussed MDT’s plans to entirely replace the bridge.

Built in 1955, Sportsman’s Bridge is just wide enough for two, 12-foot driving lanes, which Shane Stack of MDT said makes it “functionally obsolete” for the amount of traffic that crosses it each day.

The bridge is 686 feet long, which Stack said leads to harrowing travels for pedestrians as well as drivers.

“It’s a fairly long structure; 24-feet wide, that’s a fairly narrow structure,” he said.

According to MDT, the bridge sees plus-or-minus 5,200 vehicles a day on average. Stack said that amount of traffic should have at least 40 horizontal feet on a bridge deck.

Stack said the bridge is also “fracture critical,” which means a failure in the steel girders underneath could result in an all-round bridge failure because it was built without redundancy structures found in more modern bridges.

Still, Stack noted that the bridge is not falling apart and is still safe to traverse.

“It’s a perfectly safe bridge; it doesn’t mean it’s falling into the water tomorrow,” he said.

The last bridge inspection at the site was in October of 2010, with the next inspection scheduled for 2012. The bridge’s next underwater inspection will be sometime this year, Stack said.

The latest inspection gave Sportsman’s Bridge a 57.6 out of 100 for its sufficiency rating, Stack said, with points deducted for its age, narrowness and the deck conditions.

As for the new bridge, Stack said MDT is in the absolute beginning stages of designing and considering the project. MDT presented three different options for a new bridge design, none of which has been surveyed, to the audience of about a dozen people.

The new bridge would cost an estimated $15.2 million, and would take at least two years to complete. It would be built alongside – either north or south – of the current structure, Stack said, because Sportsman’s Bridge was built in such a way that would be impossible to cut it in half during construction.

New designs show two, 12-foot lanes along with 8-foot shoulders on both sides.

Stack said rough estimates put the project’s start in 2016, but that would be dependent on future MDT budgets.

Roadwork on either side of the bridge would also be redone with plant mix paving, seal and cover, striping, guardrails and 8-foot shoulders.

Members of the public at the meeting described the bridge as “hair-raising” at times and said it is imperative to replace the structure.

Jim Watson, a member of the Flathead County Weed, Parks and Recreation, told MDT staff that the bridge is a high priority in the county’s trail plan, and that new designs should consider isolating bike and pedestrian lanes from traffic.

Henry Oldenburg, who lives near the current structure, expressed deep concern for high floodwaters, to which Nigel Mends of MDT said project engineers would consult hydrologists during the projects and take a look at historical flood records.

Oldenburg also noted that vehicles entering the highway from the west side of the bridge could be endangered by added curves in the road due to visibility.

MDT staff discussed the slopes on either side of the project, which would expand the width of the construction on the roads leading up to the bridge. Mends said there would be a two-foot horizontal expansion for every vertical foot added to the road.

This would mean procuring right of way from adjoining landowners, Stack said.

The deadline for comments and opinions on the project is July 28. MDT can be contacted via email, telephone and written letters. Comment forms can be found at www.mdt.mt.gov/mdt/comment_form.shtml and mail can be sent to Shane Stack, Missoula District Preconstruction Engineer, MDT, Missoula district office, PO Box 7039, Missoula MT 59807-7039

Stack said MDT would hold more informational meetings in the future once the project takes shape.

Stay Connected with the Daily Roundup.

Sign up for our newsletter and get the best of the Beacon delivered every day to your inbox.