East Lyme — Amtrak says it needs to close the new Niantic River Bridge for 48 hours in July, and the local boating community isn’t happy about it.

A two-day closure at the height of the summer season would be a severe financial burden, several area business owners said.

“We would lose thousands of dollars,” said Bob Wadsworth, owner of the Sunbeam Fleet in Waterford. “You can’t make up those days. There are only so many days in the summer.”

The structure that opens the new bridge has to be moved half an inch, Peter Finch, the project manager for Amtrak, said Thursday. Finch said it compressed more than the mathematical models predicted it would and now the lift span is too low. The gears that lift the bridge will quickly wear out if the alignment isn’t corrected, he added.

The lift span was supposed to remain upright so boats could pass underneath while the construction continues. But, Finch said, it has to be closed so the contractor, Cianbro/Middlesex Joint Venture, can use hydraulic jacks to adjust the alignment.

“We wait for this time of year,” said Matt Hillyer, co-owner of Hillyer’s Tackle Shop in Waterford. “This is where we’ve got to make it. And to lose two days in July, I’d rather lose January and February. That’s what it means to all of us down here, probably even more. Throw in March, too.”

The contractor reported the problem to Amtrak in May. The engineering and design teams for the project finalized their recommendations for how to correct it early this month.

On Wednesday, Amtrak submitted the proposed schedule for the closure to the Coast Guard. The channel would remain open to marine traffic, but to go through boats would need to be able to pass underneath the lift span, which has a 16-foot vertical clearance restriction. The old bridge, still in use by rail traffic, can be opened.

The exact date in July has not been set.

Wadsworth said his four boats won’t fit and neither will most of the local charter boats. If the bridge could be closed only at night, Wadsworth said, that would minimize the impact substantially.

Hillyer said no one will be getting supplies at his tackle shop if the boats can’t get out.

“We need a new bridge there and we’re getting one. That’s good. But two days out of a summer season for this community is a lot,” said Hillyer, who also was worried about the people who come from far away to use the boat launch and wouldn’t necessarily know about the closure.

Lee Deer, general manager at Three Belles Marina in Niantic, said he will be dealing with a lot of upset customers if they can’t get their boats out of slips they have paid for during their summer vacations. Amtrak has proposed closures at inopportune times in the past that created a stir in the boating community, Deer added.

“We raise up enough of an uproar and they back down,” he said. “I’m hoping that will be the case again. This will probably promote a dialogue, and hopefully we’ll come to a compromise.”

j.mcdermott@theday.com