State Considers Route 3 Toll Lanes

State transportation officials are considering adding paid express lanes on a section of Route 3 south of Boston in an effort to ease congestion and improve safety.

The Massachusetts Department of Transportation is considering two optional toll lanes along a 17-mile stretch of the highway from the Norwell-Marshfield line, north of Exit 12, to the Braintree split.

Agency spokesman Michael Verseckes says a private entity such as a bank or investment firm would pay for the costs of construction, which could run as high as $800 million and would recoup those costs through toll revenues.

He says there are no plans for wider north-south tolls.