BELLOWS FALLS — Engineers from the Vermont Agency of Transportation told Rockingham and Bellows Falls officials last week that the original plan to replace the historic Depot Street Bridge has dramatically escalated in price because of complications associated with the Great River hydro facility.
The bridge, which is one of two bridges that connect The Island to the rest of downtown Bellows Falls, crosses the Bellows Falls Canal, which is owned by the power company and acts as the main penstock for the Great River Hydro facility.
The original plan for the $3.4 million new bridge, which would have strongly resembled the current 1909 bridge with a concrete arch, would require the hydro plant to cease power generation for several months, and could trigger $120,000-a-hour power generation fines in the event of a regional power emergency, the engineers said.
Great River Hydro expects to be reimbursed for any lost revenue, he said.
The news of the financial ramifications from the nearby hydro plant were not discussed 18 months ago, when the Rockingham Select Board voted 3-2 to endorse replacing the bridge largely in its current location.
The main alternative to the current location is to build a new bridge, slightly north of the existing location, with a new truck-friendly alignment that would start near the rear of the old Bellows Falls Garage, which is about to be converted into housing.
A proponent of the new location, Bellows Falls Trustee Stefan Golec, said the high costs associated with the hydro plant complications should push the Rockingham board to revisit moving the location of the new bridge.
Engineer Scott Burbank of consulting firm VHB said the state would have to build a coffer dam in order to build a new arch, which would require the canal/penstock to be largely left dry. The canal walls are in such poor shape that the coffer dam is required, he said, adding $2.1 million to the cost.
The loss of electrical revenue could run between $200,000 to $600,000 a month, Burbank said, adding another $1.6 to $4.8 million, plus the potential $120,000 hourly fine from ISO-New England in the event of power emergency.
In addition, the 1909 Depot Street Bridge is considered historic and is on local and state registers, according to Kyle Obenauer, the senior architectural historian for the Agency of Transportation. The state is now proposing a steel truss bridge, which actually resembles the bridge that was there prior to the current bridge, the state said.
Originally, the state planned to replace the bridge with a 102-foot-long precast concrete arch.
The bridge has “spalling” or peeling concrete, exposed rebar, and is considered “structurally deficient,” by the state.
The high costs of the original plan stunned the boards, but they didn’t make a decision on which route to take. They asked the Agency of Transportation, and its consulting engineers, to get back to them with firm financial estimates of the various options.
One of those options includes turning the current bridge into a recreation pedestrian and bicycle bridge, like the famous “Bridge of Flowers” railroad bridge in Shelburne Falls, Mass.
The town and the village of Bellows Falls is coping with four different bridges in various states of disrepair in the downtown area. The New Arch Bridge, also known by New Hampshire authorities as the Church Street Bridge, is undergoing repairs this summer and fall and is down to one lane. The Vilas Bridge is closed, the Depot Street Bridge is in significant disrepair and about to be replaced, and the Bridge Street Bridge, which is located near the Bellows Falls Post Office, is also in need of significant repair.
In 2019, concerns were raised about the turning radius needed for large trucks on the west end of the Depot Street Bridge, Selectboard Chairman Peter Golec said.
Burbank said the engineers took a look at that issue, and slightly adjusted the bridge to improve those angles. Nonetheless, he said, it still encroaches on ongoing traffic at the stop sign.
The town owns the bridge, and would have to pay a portion of the replacement costs, including any power costs, according to Jon Griffin from the Agency of Transportation. Griffin said the state also found environmental contaminants in the area, adding clean up costs.
The Agency of Transportation will return to the Rockingham board with updated cost estimates.
“I think we need to know what is the cost difference,” said Rockingham Select Board member Bonnie North, who said while she wasn’t on the board for the 2019 vote, she favored the so-called “off-alignment” location.
Town Manager Scott Pickup questioned whether the delay in engineering would jeopardize any funding deadlines, but was reassured by the state engineers it would not.
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