Interstate 495 traffic is following a new pattern today in the Lawrence and Andover areas as demolition begins on portions of the bridges over Route 28.
Lanes were scheduled to begin closing Sunday night, while detours go into use overnight from 10 p.m. to 5 a.m. the following morning for approximately three weeks.
The Massachusetts Department of Transportation said there will be lane closings on I-495 and full shutdowns of Route 28 north and south where it passes below the interstate to allow crews to demolish portions of the bridges carrying I-495.
Police details and signage will be used to assist traffic flow around the work zones.
During the closure of Route 28 under I-495, traffic that would normally travel overnight along Route 28 southbound and then reverse direction to access destinations on Binney Street or Shepley Street will not be able to do so. To maintain access to residential areas, the section of Route 28 locally known as South Union Street will operate in a two-way condition with police details.