Glacier Park finds new route for bridge replacement

Glacier National Park officials met with stakeholders for the second time Tuesday afternoon to discuss the proposed replacement of the Upper McDonald Creek Bridge, one month after a contentious first meeting left the future of the project in question.

After four weeks of redesign and tweaking, the new version of the project appears to meet the approval of both sides and is scheduled to begin work with tree clearing as soon as Sept. 12.

“That first plan did not really take into consideration the landowners ability to get back and forth and also, our communication could have been better,” Glacier Park Superintendent Dave Roemer said. “So, we went back to the drawing board and looked at how we could alter that design so that the project could succeed without having an undue impact on the landowners and their access to their lands.”

The original design involved building the new bridge above the existing one, which would have severely restricted access to the west side of the creek during construction. The redesigned project now has the new bridge being constructed approximately 30 feet upstream from the current bridge, preserving the use of the old bridge until construction is complete and the old bridge is removed.

“I think we have got it right with this new design,” Roemer said. “This design balances the concerns that we have heard in a way where we all win. All of this reviewing of plans and coming back again may have looked a bit humorous at the beginning, but I think we got to where we wanted to be.”

The planned project would replace the existing single-lane bridge and its two in-stream piers with a single-lane, clear span bridge with two sidewalks, one on each side. In addition, the project would formalize parking for the Upper McDonald Creek Trailhead west of the bridge, likely with 10 delineated head-in parking spaces. The new bridge would be approximately eight feet higher than the existing bridge.

The first bridge over the creek was constructed in 1926. That bridge was reconstructed in 1936 after repeated flood damage. After the 1964 flood washed out the bridge, the existing bridge was built in 1965.

Severe flooding in 2006 damaged the bridge, including a crack in a central girder and collapsing piers. Repairs over the years have resulted in short-lived improvements, but the current structural condition of the bridge is considered poor with loads crossing the bridge restricted to 15 tons.

“From a bridge engineering standpoint, the current bridge is becoming structurally obsolete. As we continue in time, the timber is not getting any younger and will deteriorate more and more. To continue to invest in the current bridge with more repairs is not the right thing to do,” Federal Highway Administration Project Engineer Michael Traffalis said. “It’s the right time to replace the bridge before its load capacity becomes so low that you could maybe drive a Prius across it. We don’t want to get to that point.”

Even with the new design, access to the area will be restricted and delays are expected.

The existing bridge would continue to be available for Park Service and landowner access during construction. The construction area would be closed to public access for the duration of the work. Traffic delays would be minimized as much as possible, with 30 to 60-minute closures expected. Full closures, possibly for two to three days at a time, would be necessary at times for safety (such as during crane operations).

The construction area, extending approximately 100-feet from Going-to-the-Sun Road to Upper McDonald Creek Trailhead, would be closed to public access for the duration of construction.

In an effort to mitigate impacts on wildlife, restrictions have been placed on the new construction, mostly during nighttime and corpuscular hours at sunrise and sunset.

In addition, tree clearing work would be completed before Oct. 1 of this year to limit the impact on nesting bird species in the spring.

A biological impact study completed by the park found the project could disturb or temporarily displace grizzly bears and Canada lynx, but effects would not alter the large-scale distribution of either species. The project could also disturb or displace individual bull trout, but the effects would not impact bull trout populations or persistence.

“A lot of the environmental compliance and analysis goes back two years, so that gave us a huge advantage to be able to redesign the project. That being said, we have put a lot of work into it over the past couple of weeks,” Roemer said.

Replacing the Upper McDonald Creek Bridge with a new bridge slightly offset from the existing location and alignment was approved under a categorical exclusion in May of 2021 and the park believes the redesigned project could still be categorically excluded and would not require preparation of an environmental assessment.

The park plans to implement erosion and turbidity control to help combat minor sedimentation that may occur during the project and will minimize tree removal whenever possible. Sensitive species of plants would be salvaged for replanting.

The overall permanent impact of the project is expected to be 0.7 acre after restoration, including the area of the existing bridge, is completed.

Public scoping is being conducted based on the redesign to determine if there is any other information or additional concerns the park is not aware of that might result in the need for an EA.

Comments can be posted on the NPS PEPC website or sent by mail to Superintendent, Glacier National Park, Attn: UMC Bridge Replacement, P.O. Box 128, West Glacier, Montana, 59936. The comment period ends Aug. 30.

Reporter Jeremy Weber can be reached at jweber@dailyinterlake.com.