Subway Extension Price Jumps in Philadelphia

A proposal to extend the Broad Street subway line in Philadelphia is intended to attract new commercial and residential development in the city's Navy Yard. A change in construction technique is driving up the cost, however.

1 minute read

April 8, 2018, 9:00 AM PDT

By James Brasuell @CasualBrasuell


Jim Saksa reports from Philadelphia: "Extending the Broad Street Subway to the Navy Yard would cost upwards of $380 million more than originally anticipated when the proposal to extend the city’s north-south transit line down to the growing South Philadelphia business hub was first introduced in 2008."

SEPTA is wrapping up a feasibility study of the subway extension, planning to release the study in the coming weeks. The study was originally scheduled for release last summer.

The extra costs arise from the need to use a tunnel boring machine rather than cut and cover. According to Saksa's reporting the boring machine could complete the project faster and with no impact on traffic, but will likely cost 40 to 50 percent more.

The report will detail three alternatives for project.

Friday, April 6, 2018 in PlanPhilly

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