PORTSMOUTH, N.H. — The final span of the new Memorial Bridge connecting New Hampshire and Maine is scheduled to be floated into place.

The U.S. Coast Guard has closed the Piscataqua River to maritime traffic early Monday to allow contractor Archer Western full access to the bridge and start the float-in.

Archer Western had assembled the span aboard the barge Cape Cod, which is docked at the Port of New Hampshire.

It’s the most complicated of three spans to put into place. The barge needs to be removed from the channel, requiring an adjustment to 64 counterweight rope connections, and electrical connections to the towers will be time-consuming.

River traffic won’t be allowed for five days as the bridge is hooked up and tested. Traffic would resume on June 22.

The arrangement is similar to a three-day closure in February 2012 that took place when the old bridge’s center span was removed.

The new bridge is replacing a nearly 90-year-old bridge connecting Portsmouth to Kittery, Maine. The design reuses the original 1922 piers as the base for the modern supports. It will continue to display the 1924 memorial tablet and beaux arts decoration fabricated by the Gorham Bronze Co. of Providence, R.I.

The float-in was originally scheduled for June 10, but equipment repairs needed on a large crane delayed the date.

Project manager Stephen DelGrosso said it is too early to tell if the bridge opening date will be affected.

“We still expect to open the bridge to traffic in July,” he said.