KENNEBUNK – Traffic along Route 35, the main road into Kennebunkport, was rerouted early Tuesday as work got under way on a replacement for a bridge that was damaged beyond repair in July.

A temporary span has been in place since the old bridge over the railroad right of way used by Amtrak’s Downeaster buckled during a track overhaul.

The Maine Department of Transportation has set Nov. 22 as the tentative target date for completion of the new bridge. It will be built of concrete resting on steel pilings driven down through 60 feet of soft clay to bedrock.

The Kennebunk-Kennebunkport Chamber of Commerce opposed the plan to close the bridge this fall, saying it would hurt seaside businesses that earn a quarter of their annual income between October and December.

The MDOT brushed aside a chamber official’s proposal to keep one lane of Route 35 open until Christmas, then close the bridge during January’s tourism slowdown.

That option would have added several months and at least $1 million to construction costs that are expected to exceed $1.5 million.

While business owners on Routes 35 and 9A from the Summer Street Bridge to Lower Village agree that the work is needed, they expect a drop in sales during the construction period.

“We’re the most affected,” said Morey Highbarger, owner of The Landing Store. “Look at the detours. Our business relies on drive-by traffic.”