If this was really a railroad bridge I think it would be hard to even consider the Pratt a 1909 structure, let alone the Whipple. By 1909, railroad bridges were far more massive than this. Could this be a bridge relocated and reused in this place in 1909?
Either way, an excellent find, I was unaware of this rare bridge in DC.
This bridge looks to be much older than dated.
The Pratt could be 1909 but the Whipple would be pre-1900.
Bridge has a curve built it. Not sure of the builder though. Here is a image from the deck where you can see the curve. http://www.flickr.com/photos/mvjantzen/248793397/
Bridge was added to most endangered list by the local historical group.
This bridge was built in 1831, not 1800, by Isaac McCord and Co. See the Historic Resource Study by Harlan D. Unrau at www.nps.gov/history/history/online_books/choh/unrau_hrs.pdf
This bridge is much more than is currently described here. Sealed within this bridge is one of only two cast iron deck arch bridges in the United States (the other of course is Dunlaps Creek Bridge in Brownsville, PA). The Pennsylvania Avenue Bridge is unique, as the cast iron tubular arches of this bridge were designed to carry water within themselves. In other words, the arch ribs of the bridge are water mains. According to HAER they still carry water, encased within the 1915 arch bridge. They are visible both in HAER documentation and in Google Street View.
This page is a double listing, here is the main page: http://bridgehunter.com/dc/washington/632IIII3300015P/
Found this blog post with a photo of this bridge being built - just the formwork was up.
whoops, looking again I see I'm not quite right. This page is for the smaller bridge; I believe this photo is of the larger neighboring bridge.
Found this blog post with a photo of this bridge being built - just the formwork was up.