Re:An interactive exploration of Boston's subway system
by cowsandmilk on Tuesday June 10, 2014 @12:29PM
(#7873521)
> tunneling is monstrously expensive
it is even more expensive in parts of Boston known for having the worst problems. The Green Line (which isn't even analyzed) runs through Back Bay, which is largely landfill[1] without very good engineering properties. Combine this with running under many buildings that are National Historic Landmarks[2][3][4] and have shown shifting with bits of construction such as adding an elevator[5], these tunnels are pretty much impossible to expand.
it is even more expensive in parts of Boston known for having the worst problems. The Green Line (which isn't even analyzed) runs through Back Bay, which is largely landfill[1] without very good engineering properties. Combine this with running under many buildings that are National Historic Landmarks[2][3][4] and have shown shifting with bits of construction such as adding an elevator[5], these tunnels are pretty much impossible to expand.
[1] http://www.bc.edu/bc_org/avp/cas/fnart/fa267/boston/bos1820.... [2] http://en.wikipedia.org/wiki/Boston_Public_Library,_McKim_Bu... [3] http://en.wikipedia.org/wiki/Old_South_Church_in_Boston [4] http://en.wikipedia.org/wiki/Trinity_Church,_Boston [5] http://www.boston.com/news/local/massachusetts/articles/2008...