Photo taken by Denimadept
License: Creative Commons Attribution (CC BY)
View this photo on Wikipedia
The bridge is open to traffic.
http://articles.courant.com/2010-11-03/community/hc-marteka-railroad-swing-bridge-110720101103_1_swing-bridge-arrigoni-bridge-providence-worcester-railroad
If this is the bridge I think it is, just downstream from the Arrigoni Bridge, it's NOT open to traffic. On Wikipedia, it's known as http://en.wikipedia.org/wiki/Providence_%26_Worcester_railroad_bridge