MDT expects Dalton Mountain Bridge replacement in 2023

Although it was the last major point of discussion at Lincoln Government Day, an update on the progress of the Dalton Mountain Road Bridge replacement was a key subject during the Aug. 2 meeting.

Montana Department of Transportation District 3 Administrator Jim Wingerter and Jimmy Combs, the District 3 pre-construction engineer were on hand for the meeting, to hear concerns about local MDT efforts, as well as to provide their perspective.

The Dalton Mountain Bridge has been a particular concern for Lincoln since MDT agreed to include it in their Off-Systems Bridge Program in 2019.

The bridge has been limited to one lane of traffic for the last four years due to failing bridge piles, prompting residents of the area to question both the length of time it's taking to get a new bridge in place, and when they can actually expect to see it.

Currently the state is looking at a construction date in 2023, based on the scheduling for design and prep work and where it fell on the Off-System Bridge Program funding plan.

Estimated replacement dates have changed from 2019 to 2020 under Lewis and Clark County to 2022 and now 2023 under MDT.

Last fall, MDT hired Great West Engineering of Helena, which developed the Preliminary Engineering Report for the county in 2017 and 2018 for the Treasure State Endowment Program grant application for the project.

Karl Yakawich of Great West explained where things currently stand.

"Where we're at right now with the project, we are into a 30 percent design stage." he said. "We've got some initial road alignments down; we've got our bridge alternatives that are on paper and we're going to be submitting that to the Department of Transportation and the county."

"We started this past fall and were able to get all the field surveys done," Yakawich, said. Crews completed terrain and river surveys, property line surveys, cultural surveys, mapped utilities and conducted soil investigations at the bridge site down to 100 feet.

"One big driver of this project is what the river looks like when it floods," Yakawich said. "What does that 25-year event or 100-year event look like?"

He said that information lets them set the bridge elevation, which will likely be about three feet higher that it is now.

Yakawich said they are considering three designs: a single-span pony truss, a two-span concrete, or a three-span concrete bridge.

In early discussions about the bridge replacement at the county, a single-span bridge seemed to be the best bet but was more expensive. Initially under MDT, a double span with one pier in the river seemed more likely.

Ron Zarr, vice chair of the Upper Blackfoot Valley Community Council and a resident of the area south of the bridge questioned the need for the three options. Yakawich said they were tasked with looking at three so they could understand the hydraulic impact as well as the differences in cost. He said the pony truss, supported by a series of steel trusses the length of the bridge, is looking like a good alternative, both in terms of allowing debris to pass underneath it and because it would save construction time with less work in the river.

"Our next step is to present those (bridge options) to the public this fall, seek your input," Yakawich said. "We have some plans down on paper. we want your thoughts on what you like and what you don't like. We're really starting the public outreach component this fall."

Ultimately, Pat Hagen, a resident of the area accessed by the Dalton Bridge, asked the question on many people minds: why does the date keep getting pushed back?

"The bottom line is they have to jump through more hoops than the county does," said Eric Griffin, Lewis and Clark County Public Works Supervisor.

"When we get involved with federal highways and their funding, there are a whole lot of boxes we have to check. that all takes time," Wingerter added. "It just boggles my mind to get a project from 'hey, what if we do this?' to when we actually put boots on the ground and are working on the project"

He also said the changing timeframes aren't due to animus toward Lincoln. He noted that the night before, they were in Belt to kick off the final phase of the Belt North and South Project on U.S Highway 87, a project that has been ongoing for 20 years.

"Yes, it does take a lot of time. Yes, it is frustrating for you folks. I understand that; we understand that as an agency," he said.

Last September the bridge replacement was projected to cost $2.387 million under the Off-system Bridge Program. The state is funding the cost of all the survey and design work, with the county contributing the funds from the TSEP grant.

'When they start construction...we get a notice of that. We go sign a check for the entire TSEP grant and we hand it to them," said Lewis and Clark County Engineer Dan Karlin.

Karlin provided a background on the bridge issues, which were first flagged in 2016. Late that summer, a bi-annual inspection of the bridge found issues with some of the wooden piles that needed to be addressed. He said they started planning in December for work that could have restored them to full capacity, but by the spring of 2017 the pile had deteriorated further. "We knew we had to get something done. We got everything ordered. Things take a while, especially specific things like that, to get in," Karlin said, but also noted that when wood piles start to deteriorate, they can go really fast.

In early August, 2017 another inspection found several failed piles that spanned side-to-side across the bridge, which led to the bridge closure Aug 3. 2017.

"'We chose to repair four of those piles on one single lane so we could keep the bridge open," Karlin said.

The bridge re-opened as a single lane with a 10-ton weight limit Sept. 14, 2017, and the County set to work preparing a grant application for the Treasure State Endowment Program to help fund the cost of replacing the bridge.

The Montana Legislature approved the $558,806 grant during their 2019 session and Lewis and Clark County began discussion with MDT to include it in their Off-System Bridge Program. MDT agreed to team up with the county in November of 2019.

A word on speed, no passing zones

Before the meeting dove into the Dalton Bridge issue, Jimmy Combs explained where things stand with the change to the speed limit from the east edge of Lincoln to the Lincoln Airport, as well as with the status of the requested "no passing" zones both east and west of town.

"We did get the speed zone approved by the transpiration commission," he said. "We're in the process of ordering signs now. As soon as we get them done, we'll get those signs installed."

He said they also did some observations related to the "no passing" zones.

The request for a no passing zone west of town stemmed from a number of accidents, and the potential for more, near the entrances to the Lincoln Ranger Station and Sculpture in the Wild.

"One of the things we noticed is that the Forest Service office is closed," Combs said. "Part of what we're looking for is how much traffic is turning on and off the highway."

With the office closed it doesn't; provide the most accurate picture of the situation

"There are fairly specific warrants for just about anything we do travel-control wise," he said. "We've got to be able to justify it. we're trying to collect some data, some meaningful data, we can look at to see if we can justify a passing zone or not."

Although Sculpture in the Wild was able to provide visitor counts for the study, the Forest Service doesn't maintain visitor logs that could help provide insight into traffic in and out of the station. Lincoln District Ranger Rob Gump said he's aware of two employees who were in accidents while turning into the station from the westbound lane. That prompted the policy that, if there is traffic, Forest Service vehicles in the westbound lane should go into town and turn around, so they can turn into the station from the eastbound lane.

Wingerter, who explained that District 3 extends from Helena to the Ft. Belknap Reservation, then west along the Canadian border to the Blackfoot Reservation and south again to Helena, said everybody in the district wants some sort of sign or no passing zone, but doing so affects efficiency of traffic, as well as the bottom line in the budgets.

We have to, as Jim says, meet the warrants we receive for putting in no passing zones," he said. "We will do what we can to meet the warrants and provide what we can in the community itself."