Tobin Bridge is structurally deficient - SoxFan now has something else to worry about besides the Red Sox. The Federal Highway Administration has rated 588 bridges (including the Tobin Bridge) in Massachusetts as "structurally deficient," 100 busiest structurally deficient bridges in Massachusetts. http://www.boston.com/news/local/massachusetts/articles/2007/08/03/busiest_deficient_bridges/ It's not hard to guess why the Tobin Bridge is so busy.