[W]ESTMINSTER – Within the past five years, the state Agency of Transportation has undertaken more than $100 million worth of bridge work on Interstate 91 in Windham County.
And there’s more on the way.
Agency officials say they’re planning a major repair project on two interstate bridges stretching over the Saxtons River and Route 121 in Westminster. Work has been pushed out to 2020-2021 due to a lack of funding for a project carrying an estimated $10 million price tag.
Officials say similarities in age and design – as well as exposure to winter weather – are driving multiple expensive bridge repair and replacement projects on I-91.
“I think it’s mainly that the concrete decks are at the end of their useful life,” said Mike Chenette, a South Burlington-based engineer who’s involved with the Westminster project. “That’s pretty general, right up all the way through 91. (And) they’ve all been salted about the same amount.”
The state recently wrapped up four years of work on a $60 million new bridge carrying I-91 over Route 30 and the West River in Brattleboro.
A short drive up the highway, work began this year on a $44.3 million replacement of an interstate bridge in Rockingham. Traffic has been reduced to one lane each way for the project, which is expected to finish in early 2020.
That’s just in time for the Westminster project to start.
Located about 2.5 miles north of Exit 5, the two bridges over the Saxtons River are more than 500 feet long and are made up of multiple spans. They carry an average of 6,400 vehicles daily.
Officials say the bridges, which were built in 1963, have a substandard width and deteriorated decks. Leaks from the decks have damaged structures below.
“The major problem is that the decks are saturated with salt … that leads to rusting of the reinforcing that’s in the decks,” said Chenette, who works for Stantec Consulting, the project’s design engineering firm.
The project will include deck replacement and pier repairs. Officials also expect to slightly expand the shoulder area, which they say may prevent accidents.
“The shoulders are pretty narrow. We’re going to try and widen them as much as we can in this project,” Chenette said. “We can’t go quite as far as we’d like to, because we’d have to increase the width of the substructure, and we don’t want to get into modifying that.”
Crews also will be eliminating and replacing joints in the bridge decks, “so it’s going to be a much smoother ride and less leakage,” said Wendy Pelletier, project manager for the Transportation Agency.
The plan is to keep two lanes of I-91 open during the project. All traffic initially will be diverted onto the southbound bridge and then switched to the northbound bridge when work is completed on that side.
Chenette said there will be lane closures on Route 121 underneath the bridges. Also, “there could possibly be some very short periods where they need to close (Route 121) – like 15 minutes or less,” he said.
Construction could have started as soon as next year, but there’s not enough money to move forward at this point. So the plan is to start work in spring 2020 and finish in fall 2021.
“Unfortunately, the big problem is funding on this project,” Pelletier said. “It’s about a $10 million project, because all the steel is going to be cleaned and painted, and that’s quite involved.”
Still, the repair job features a much lower price tag than other recent I-91 bridge replacement projects in the area. Pelletier said the agency is “trying to do more of these repairs to extend the useful life” of interstate bridges before they must be replaced.
“The buzzword is ‘asset management’ now,” Pelletier said. “We have a group that tries to strategize where we can put the money and get the most (results).”
The repairs planned for the Westminster bridges are expected to be good for 40 years, officials said.
The Transportation Agency is planning a similar project on an I-91 bridge in Weathersfield at Exit 8, Pelletier said. It’s possible that project could be on the same schedule as the Westminster work, but that’s dependent on the availability of state and federal funding.
“What we’re doing now is trying to get as many designs done as we can and put them on the shelf” for when funding is available, Pelletier said.
