VTrans outlines Main Street bridge replacement plan, flags contaminated‑soil costs and scheduling risks

Gary LaRoche, project manager for the Vermont Agency of Transportation, presented final plans for replacing the Main Street bridge in Northfield Village during the Northfield Select Board meeting. He said the two‑abutment, single‑span bridge would be about 140 feet long, replace the existing three‑span structure and remove in‑channel piers to improve debris flow. The design includes wider sidewalks (7 feet), an 11‑foot travel lane, and a 5‑foot bike lane separated by a 3‑foot buffer.

LaRoche said VTrans has completed final plans, specifications and an engineer’s estimate and expects to advertise the contract on Sept. 10, 2025, with construction starting April 1, 2026. He described a planned 12‑week full bridge closure for major construction and a regional truck detour of roughly 26 miles. "We're planning to detour truck traffic on a regional route and provide a local detour for bikes and pedestrians," he said.

The presentation flagged two community concerns that shaped the design and construction plan. First, LaRoche said the project must provide an ADA‑compliant temporary pedestrian detour because the existing bridge has sidewalks; that detour will be treated as temporary work the contractor removes after the project. Second, extensive utility relocations are under way and the project has executed utility agreements with the town to move overhead lines underground and install duct banks.

LaRoche warned about contaminated soils encountered in and near the project limits. He said the project must follow a soil management plan approved by the Vermont Department of Environmental Conservation and that the agency estimated a worst‑case soil disposal cost of $500,000 — an allowance included to avoid underbudgeting for petroleum‑contaminated soils. "We estimated, kind of worst‑case scenario, $500,000 for disposal of soils," LaRoche said, adding the town can apply for reimbursement through DEC’s petroleum unit when eligible.

On project cost sharing, LaRoche said the town’s share would be 5% of total construction if the board agrees to the 12‑week full closure; had a temporary bridge been used instead, the town’s share would have been about 10 percent. He gave a preliminary engineering estimate and line items for design, construction engineering and contingency; LaRoche noted rising inflation and additional design work related to removal of the nearby Cross Brothers Dam had increased construction estimates.

Board members and residents pressed LaRoche on operations: how the detour would route pedestrians across existing railroad crossings, whether Amtrak and New England Central Railroad had been or would be notified, and whether temporary stop signs or signals could be installed at local intersections. Nancy Avery, VTrans work‑zone safety engineer, said signal warrants have to be met and that temporary signs are more typical for the pedestrian detour. LaRoche said the right‑of‑entry agreement with New England Central Railroad and other clearances are required before we advertise; he told the board the Federal Highway Administration requires VTrans to document permits and clearances for stewardship and oversight reviews.

LaRoche also warned of a scheduling risk: budget and revenue forecasts at the state level could delay project advertisement and construction. "Only an hour, like, an hour before I got here, I received a phone call from our program manager. Due to budget revenue forecast, there's possibility of revenue downgrades...the project may need to be pushed because there's no money to build it," he said.

The presentation concluded with schedule milestones and contingency planning. LaRoche said his team is moving contract plans forward, expects to advertise in September, and intends to have the bridge open for traffic by Labor Day 2026 following the 12‑week closure. He invited follow‑up technical questions about soil testing and permitting from the DEC contamination unit.

Next steps: VTrans will finalize contract plans, coordinate utility clearances and right‑of‑entry with the railroad, and notify the town if state funding forecasts change. If the town directs permanent traffic changes (for example, installing stop signs by ordinance), that would be a separate local decision that could affect what temporary work the project does during construction.