Over the following year, SEPTA undertook a 10-month, $354 million (equivalent to $ million in ) project to overhaul the viaduct, labeled "RailWorks." The viaduct was shut down completely from April 5 to October 3, 1992, and from May 2 to September 4, 1993, with the R6 Norristown, R7 Chestnut Hill East, and R8 Fox Chase lines suspended. Other Reading lines only came as far into the city as the Fern Rock Transportation Center, where riders had to transfer to the Broad Street Line. Express trackage was added to the Broad Street Line to improve travel times from Center City to Fern Rock. Nonetheless, the number of subway trains needed to carry both regular Broad Street Line riders, as well as passengers transferring to the subway because of RailWorks, exceeded the capacity of the above-ground, two-track, stub-end Fern Rock terminus. In 1993, SEPTA added a loop track to Fern Rock Yard, so that northbound trains did not need to use the crossovers at the station throat, somewhat ameliorating the problem. During peak hours, SEPTA ran several diesel trains from the Reading side branches, along non-electrified Conrail trackage, to 30th Street Station.