The historic Tilton Island Bridge is on track to get repaired after being shut for five years unless the Trump administration decides to yank back a federal grant.

The Tilton Select Board unanimously approved a $524,800 contract Thursday night with Arnold M. Graton, a Holderness company that specializes in restoring historic bridges. Company representatives told the board that the firm would remove the 145-year-old cast-iron bridge with a crane, take it to their shop to fix it over the winter, then replace it next year.

But that depends on a $500,000 grant from the U.S Park Foundation coming through. The grant was awarded, but its status is unclear due to confusion over what the Trump administration is doing with grants throughout the federal government.

“We have no answer yet, but we are moving up on the schedule; might have approval as soon as June 1,” said Town Administrator Scott Hilliard.

If the grant comes through, Hilliard said, the plan is to start work sometime after the Laconia Motorcycle Week in mid-June. It would not happen during the annual event because removing the 85-foot bridge in two sections using a 475-ton crane will require closing Route 3 for a period, which would snarl the heavy traffic that uses the road during Bike Week.

The pedestrian bridge was built in 1881 to connect the town with Tilton Island Park, which has long been used as a public gathering place on a small island in the middle of the Winnipesaukee River. It is a rare surviving example of a bridge made with cast iron using a patent issued to Lucius Truesdell. The bridge was listed on the National Register of Historic Places in 1980.

The bridge was closed in 2021 because of safety concerns related to the condition of the iron. Timothy Dansereau, a vice president with the Graton company, said the problem was especially bad on the end adjacent to Route 3, where road salt has caused the metal to rust.

The hardest part of the repair, he said, would involve replacing decorative cast-iron pieces that give the bridge its unusual appearance.

“The longest part of the process will be casting new upright, ornamental pieces. They have to have sand casts made for the pieces and that takes months. It would be done through the winter,” Dansereau said.

Cast-iron pieces are made by pouring molten metal into moulds, where it is allowed to harden before being removed from the cavity. Sand casting, as the name implies, uses moulds made of sand that can be destroyed to release the iron piece.

Until 2021, the island park was split between Tilton and Northfield, with the border running down the middle, even though Northfield never had a bridge connecting to it. In that year, both towns approved moving the border so that Tilton owns the entire island.

David Brooks can be reached at dbrooks@cmonitor.com