I-89 Bridges on To-Do List; 10-Year Plan Calls for Widening Spans Beginning in 2018
Surveyors Ted Bemetter, left, and David Cloutier from the New Hampshire Department of Transportation collect data near the I-89 bridge in West Lebanon, N.H., on March 25, 2014. "They'll make a three-dimensional map (from the data) and figure out what the best design will be for what they want to do," Bemetter said. (Valley News - Will Parson) Purchase photo reprints »
Lebanon — About 38,000 vehicles each day cross the Interstate 89 bridges spanning the Connecticut River between Lebanon and Hartford.
“More people drive over those bridges than any other piece of infrastructure in our region,” said Nate Miller, executive director of the Upper Valley Lake Sunapee Regional Planning Commission.
The nearly 50-year-old twin bridges are slated for rehabilitation beginning in 2018, according to the state’s draft 10-year transportation improvement plan.
“That should happen ... short of federal aid getting cut back,” said state Rep. David Campbell, D-Nashua chairman of the Public Works and Highways Committee.
The project will address safety concerns by widening the southbound side of the highway to create a longer merge lane. Currently, a ledge outcropping restricts sight distance for those entering I-89 South from I-91, forcing drivers already traveling on I-89 to move to the left lane to accommodate entering traffic.
“It was one of the things you could see pretty early we’re going to correct,” said Bob Landry, consultant design chief for the Department of Transportation.
A traffic study, completed last April, suggests that lengthening the merger lane may help to decrease accidents in that area.
Officials will also widen the shoulders — now three feet on either side — to 10 feet on one side, creating a breakdown lane, and four feet on the other.
Landry anticipates scheduling public information sessions this year in Lebanon and Hartford. Those events will give residents an opportunity to hear details about the project and to provide feedback to officials.
Specifically, the public might provide Landry with information about special circumstances that might alter traffic patterns or volume, or about common “near miss” safety concerns, he said.
The project aims to repair the bridges’ decks and some details of the steel supporting structures, which have deteriorated since their construction in 1966.
The state of the bridges and their importance to the region is such that they are now ranked 36th and 37th on the state’s “red list,” flagged bridges in need of repair or replacement.
Being on the redlist — as 145 New Hampshire bridges are — means that Department of Transportation officials inspect them every six months, said Landry.
The twin bridges are an example of high priority needs, deserving of their share of the state’s scarce resources, said Campbell.
He said the state’s 10-year plan, which the House of Representatives approved Tuesday, is “fiscally constrained” and based on the federal aid it anticipates.
“We worked in a bipartisan manner to really scrub it from projects that really aren’t ready,” he said.
Landry estimates the project — including design and construction — will cost $32 million, which will be shared between the twin states. New Hampshire will shoulder 76 percent, while Vermont will chip in the rest. Landry’s estimate, which does not take into account inflation, is down from the $38 million included in the draft 10-year plan.
The state has contracted design work — slated to be completed by the end of the year — to McFarland Johnson, an engineering firm with an office in Concord.
Planned repairs include improvements to the bridge decks and replacement of some elements of the steel structures, Landry said.
To accommodate traffic flow on the bridges during construction, Landry anticipates maintaining two lanes for each direction of travel, he said.
He said he had hoped to find a way to “stay out of the water” by finding an innovative way to work between the piers, but it now looks as though that will not be possible. Instead, the plan is to install another column and “fill-in in-between,” he said.
Construction will likely take place in three phases over three years, as is typical, he said. The first phase will be to install the new pier in the water and create temporary lanes between the two bridges. Work will proceed by replacing the deck on one side of the bridge and then the other.
Landry said he anticipates the work to be completed entirely within the state’s right of way, which will help to streamline the process.
Before creating a precise schedule for the project, Landry said his department will communicate with environmental groups on both sides of the river: the New Hampshire Department of Environmental Services, Vermont’s Agency of Natural Resources, as well as federal groups such as the U.S. Army Corps of Engineers, the U.S. Coast Guard and the U.S. Fish & Wildlife Service.
They will consider concerns such as fish spawning patterns in determining when to perform work in the river, he said.
Nora Doyle-Burr can be reached at firstname.lastname@example.org or 603-727-3213.