The MBTA will close the Red Line north of Harvard Square on four weekends in November and December in a continued effort to remove and replace corroded stretches along the track.
Buses will replace the trains along the stretch of the Red Line on the weekends of Nov. 17-18; Nov. 24-25, Dec. 1-2 and December 8-9, according to the MBTA.
The Porter, Davis and Alewife stations have about 21,000 passenger boardings on a typical Saturday, and about 14,000 boardings on Sundays.
MBTA spokesman Joe Pesaturo said Wednesday that the work is an extension of construction that began last fall along the same stretch of track forcing closures of the stations and shuttle bus service on weekends for four months.
Pesaturo said the MBTA made it clear last year that the work would be a multi-year project.
The work this fall is part of a $34 million project being funded through the MBTA’s capital improvement plan and crews will be removing and replacing corroded concrete slabs along the track, according to the MBTA.
The portion of the Red Line track opened in 1985, and uses concrete slabs resting on absorbent rubber disks to cushion noise and vibration for above-ground neighbors.
Workers will also be replacing track and the power rail and will address leaks in the tunnel to prevent further deterioration.
The stations have to be closed on weekends because the work can not be completed during the short overnight periods in which the Red Line is not operating, according to the MBTA.