The piers with reddish stone and angular ends are original B&P construction
circa 1870. To reduce flooding concerns, during 1898 the Wilson Brothers
Company contracted to lengthen the bridge via three new stone piers. Those
have rounded ends, such as the closest in this view. At the same time the
company likely also widened the bridge from two to three tracks.
The "1928" embossed in concrete reveals when the piers were widened on
this, the downstream side, in preparation for electrification of the line.
A fourth track is scheduled for addition here during the 2020s. Whether
that will require a total rebuild of this bridge is not yet clear. Perhaps
it can be tacked on in the manner of the prior expansions.
Link to older picture: