Photo: 20190417-news-bridgework

On Tuesday, employees of Miller Construction Inc. of Windsor, Vt., began a six-month rehabilitation of the US 302 Bridge in Bethlehem by removing the median island on the bridge.

BETHLEHEM — Drivers should expect delays and detours here and in neighboring Franconia as the New Hampshire Department of Transportation on Tuesday started one bridge-repair project and began finalizing a second.

In the former project, Miller Construction Inc. of Windsor, Vt., is charged with doing a variety of work, at a cost of $1.33 million, to help protect the integrity of the U.S. Route 302 Bridge over Interstate 93 at Exit 40.

That work, said Dan Caouette, who is a member of the NH DOT’s Construction Bureau and the contract administrator for the project, will entail removal of the median island on the bridge, which, thanks to a large crane, began Tuesday; repairs to both the bridge deck and piers; replacement of the granite curb with concrete curb; and new pavement.

During construction, which is expected to be completed by Oct. 18, the speed limit in the project zone will be reduced to 35 miles per hour. While the NH DOT believes two-way, two-lane traffic will be the norm, the agency cautioned that there may be “short-term periods of one-lane, alternating two-way traffic.”

Caouette described the work on the U.S. 302 Bridge as “a pretty typical project for us,” adding the bridge is like hundreds of others in New Hampshire.

That said, the bridge is important in that it does carry some 3,200 motor vehicles daily.

“We’re just trying to extend the life it already has,” explained Caouette. “Basically, we’re replacing the joints on it which leak and are causing issues on the piers below and we’re also going to repair any of the concrete which was impacted.”

A couple miles to the east in Franconia, the New Hampshire Route 18 Bridge over Lafayette Brook will get a more robust rehabilitation, one that will entail its closure, said Caouette.

Subject to coordination with utility companies that have assets in the area, the bridge, which is on the NH DOT’s “Red List,” may be closed as soon as sometime next week, said Caouette, or the week thereafter.

Traffic for the New Hampshire 18 Bridge will be detoured via Interstate 93 and New Hampshire Route 141 during construction, which entails removing and replacing the bridge deck and support beams; repair and reconstruction of the abutments and wingwalls; and the construction of stone-slope protection along Lafayette Brook.

NH DOT spokesman Bill Boynton said the New Hampshire 18 Bridge project will be done by Austin Construction of Concord, Vt., at a contracted cost of $1,007,031.

Caouette said the bridge should be re-opened by mid-June and work should be completed by the end of July.