I think this bridge may be the one referenced here: https://books.google.com/books?id=lCzkKkyRrS0C&q=white+bridg...
Cast portal elements would suggest ca. 1880
More than likely.
Would the bridge have been located on the river's old alignment to the east, on the other side of the dyke?
Luke the text ties into the likelihood that the bridge was close to the railroad on bridge street. I'll move the marker to where I think it should be. Let me know what you think.