Construction work to rebuild seven deteriorating bridges over the Vine Street Expressway has begun.

Construction for the four-year, $64.8-million project started early morning of Tuesday, April 14.

The project will replace seven structurally deficient bridges over Interstate 676 in Philadelphia: 22nd Street, 21st Street, Benjamin Franklin Parkway/20th Street, 19th Street, 18th Street and the Free Library and Family Court pedestrian bridges.

Crews are slated to paint new pavement markings, shift travel lanes, and install concrete barriers next week, prompting closures and detours on I-676 between Interstate 76 and Broad Street from 12:01 a.m. to 5 a.m.

Eastbound I-676 is set to be closed during those hours on Tuesday, April 14, and Thursday, April 16, while westbound lanes are set to be closed Wednesday, April 15, or Friday, April 17. An additional eastbound or westbound closure is possible Saturday.

The first of the aging structures expected to be demolished and replaced is the Family Court pedestrian bridge, scheduled to close on May 4.

Buckley & Company, Inc. is the contractor for the project, which is expected to finish in fall 2019.

Construction will be suspended during September's World Meeting of Families, PennDOT said.