LITTLETON — The state of New Hampshire is mulling options for the nine-decade-old bridge that spans the Connecticut River on Route 18 and connects Littleton to Waterford, among them rehabilitating its structures for continued vehicle use or closing the bridge to vehicular traffic to create a multi-use path.
The state has a budget of up to $4.1 million for rehabilitating the bridge.
A detour will be put in place as the work, under the current schedule to begin in 2025, is carried out.
During the Littleton Select Board’s meeting on July 25, New Hampshire Department of Transportation Senior Engineer Kevin Daigle and NHDOT Project Manager Jennifer Reczek briefed the board on the four alternatives and the time line, and encouraged residents with input or concerns to reach out to NHDOT.
“We’re here tonight as an introductory meeting on this project,” said Reczek. “This is something that we started working on and we wanted to get some feedback and make sure this town is aware that this is something we’re working on and we’ll be back to do some larger public meetings as the project progresses.”
The bridge was built in 1934 and was rebuilt in 1980, when the deck was removed and replaced with a wider deck and modifications were made to the piers, said Daigle.
In 2012, scour prevention measures were installed around the piers.
“The piers were getting undermined during high floods,” said Daigle.
Currently, the bridge is ranked eighth on the New Hampshire State Red List, with the deck having a condition rating of 6 out of 9 and both the superstructure and substructure a rating of 4 out of 9, ratings that Reczek called “a little unusual.”
Its substructure has been on the state red list since 2014.
The bridge is a 5-span continuous steel girder bridge with a concrete deck that has a total length of 529 feet and total width of 30.5 feet.
The existing bridge accommodates about 1,500 vehicles per day, about 8 percent of them trucks.
The NHDOT plans to address the poor structural condition of the bridge, specifically the superstructure and substructure, and extend the service life of the bridge and remove it from the red list.
As for the current condition, the corrosion is occurring on the spans and girders, there is considerable deterioration on the Vermont-side abutment, water is leaking through parts of the bridge and is causing more deterioration, and Pier 2 has considerable deterioration, said Daigle.
Littleton Select Board Chairman Roger Emerson is a boater who has been underneath Pier 2 when big trucks cross above.
“You will have concerns,” said Emerson. “Guaranteed. It moves.”
Pier 1 also has advanced deterioration, said Daigle.
NHDOT has conducted an in-depth analysis of the steel and piers to test for current strains and is now analyzing the data, he said.
Data collection includes a topographic survey, traffic data completed in July, a bridge inspection done in November 2020, and pier concrete testing done in late 2021.
The department has completed its data collection and is now embarking on an engineering analysis, which will be followed by a development of alternatives to present for public input, a selection of an alternative, a public meeting and hearing if required, and then final engineering and environmental permitting.
The need for acquisition of property rights is not expected.
Considerations that members of the public can weigh in on are any wetlands, threatened and endangered species, or conservation land in the vicinity of the bridge, as well as cultural and archaeological resources, said Daigle.
Because the construction was funded through the National Recovery Act of 1933, the bridge is eligible for placement on the National Historic Register, he said.
“We’re looking at four alternative for this project and will do an analysis and then come back to the town with what we are looking at, and then select one and go through the final design phase,” said Daigle.
The first alternative is to replace the deck to match the existing width and conditions.
The second alternative is to replace the superstructure.
The third is a superstructure replacement with widened deck and an accommodation of a multi-use path, an alternative that Daigle said will be more involved.
The fourth alternative is to rehabilitate the bridge to create a multi-use path, and then close the bridge to vehicle traffic and transfer ownership to the towns.
All alternatives involve rehabilitating the substructures, rehabilitating and painting any remaining steel, rehabbing the piers, and replacing the deck and bridge rail, said Daigle.
Alternatives 1 and 2 would retain the current 2-girder system and alternatives 3 and 4 would replace the steel with a multi-girder system, he said.
On this particular bridge, Reczek said New Hampshire owns 67 percent and Vermont 33 percent.
Two detours for traffic control are being studied.
One uses existing exits along Interstate 93, at Exit 1 in Vermont and Exit 44 in New Hampshire, for a total detour length of 17 miles.
The second detour alternative would total three miles and would involve the construction of a partial exit on I-93, a northbound off-ramp and southbound off-ramp.
Littleton Fire Rescue Chief Michael McQuillen favored the second detour alternative and said a shorter 3-mile detour would be preferred over one that is 17 miles because it will allow first responders to get off the highway and be able to more quickly get into Waterford or Concord if they need to.
Under the current schedule, the alternatives analysis will take place during the winter of 2023, the design phase in 2023 and 2024, and the beginning of construction in 2025.
While the current budget is $4.1 million, the final number is subject to change depending on the alternative chosen, said Daigle.
Public input is needed for such things as emergency response routes and mutual aid from adjacent states and towns; historic, environmental and safety concerns; pedestrian, bicycle and snowmobile use; recreational boating and boat launch use; and for any other concerns or comments, he said.
Emerson said his concern is construction not beginning until 2025.
Reczek said the state bridge team will speak with NHDOT’s bridge inspection team regarding his concern with Pier 2 to see if an interim repair would be necessary before the big work begins in 2025.
Although closing one lane of the bridge to create a snowmobile path in winter was discussed in Littleton in 2019, during a meeting of town officials in Waterford and Littleton and members of riding clubs in both states, it was not acted on because of concerns about traffic flow and safety.