This is a bridge opposite State Street. The house you can see in the background is stone/slate, which matched the house in the historical photograph. This may not be the same site. The original image may be the main stem Winooski River. Matt Bansak writes on 2009-05-04:
The bridge in the historical photo is likely the Main St. Bridge. The bridge in this reshoot is the Langston St. bridge.
I believe my submission is also incorrect in stating that this is the Granite St. Bridge. Upon comparison with other photos of Main St, it is more likely the Main St. Bridge.