Stonington — Work to replace two bridges on Route 1 that cross Stony Brook and Quanaduck Cove is expected to resume Tuesday, according to a state Department of Transportation spokesman.

The $3.1 million project to replace the two spans began last September and continued through the spring. During that time, an alternating one-way traffic pattern controlled by a stop sign was put in place. Cars proceeded three at a time from each side.

Town officials requested that construction be stopped from Memorial Day to Labor Day so as not to affect the tourism season.

DOT spokesman Kevin Nursick said crews will return Tuesday and traffic will return to the alternating one-way pattern.

Nursick said that keeping bridges open while work is bring done to replace them significantly extends the length of a project. But he said the project remains on schedule and is slated to be completed in May 2013.

The two bridges were built in 1939 and were considered to be structurally deficient when the replacement began. In addition to increasing safety, the flow of water under the bridges will be improved with new culverts.