THE MBTA says it expects to replace 10,700 feet of rail by the end of May on portions of the Blue, Red, and Green lines to address slow zones.
The raw number is difficult to place in context without additional information, but it suggests the transit authority must complete a huge amount of track work over the course of this year to eliminate speed restrictions of 10 miles per hour and return to the standard speed limit of 40 miles per hour.
According to the MBTA’s dashboard, speed restrictions are in place on 24 percent, or 32.5 miles, of subway track on the Red, Blue, Orange, and Green lines. Speed restrictions are safety measures – by lowering the speed that trains travel the T reduces the risk of some sort of incident on defective track.
The largest amount of track replacement in May – 8,300 feet, or a little over 1.5 miles — is slated for the Red Line, where speed restrictions currently cover 65,916 feet, or nearly 12.5 miles, of track. Current plans call for 1,950 feet of track replacement on the Blue Line and 450 feet on the Green Line.
As a point of comparison, the T replaced 14,000 feet of track on the Orange Line during the one-month shutdown of the entire line last year to bring it up to par. That line currently has speed restrictions in place on 25,000 feet, or 4.7 miles, of track.
The T’s initial plan for addressing slow zones calls for doing the work at nights and on weekends and replacing subway service with bus service.
The currently scheduled Red Line work covers the track from Park Street Station south to JFK/UMass and from there to the Ashmont and Braintree stations at the end of the line’s two southern branches. The Blue Line work is confined to the stretch of track between Government Center and Wonderland stations.
It appears a large amount of the speed restrictions were put in place after the T discovered that rail inspections using various technologies to detect defects were not followed up on with repair work.
MBTA officials have declined to say what went wrong with the inspection and repair system, saying they intend to wait until an investigation is completed by Charles L. O’Reilly of Carlson Transport Consulting, who was hired “to conduct a comprehensive review of the MBTA’s track safety inspection procedures, record keeping practices, and documentation of planning and implementation of corrective activities.”