I'm pretty familiar with the Boonville Bridge dispute. A few observations:

(1) In response to Mr. Thiel's posting of 11/1, railroad bridges in the first part of the 20th century were very definitely over engineered, primarily because of several major railroad bridge collapses in the late 19th and early 20th century (one of which was a big bridge in Canada that was being constructed by none other than Mr. Cooper - the person who developed the Cooper rating system). No self respecting bridge designer of the day wanted his name attached to yet another bridge disaster. That has served the rail industry well, as the existing bridge infrastructure has been able to accomodate modern loadings.

(2) In response to Mr. Thyle's 11/1 posting, reusing bridge spans is an old tradition in the rail industry. One current example is the new UP Kate Shelly bridge in Iowa, which is using bridge spans from the former Milwaukee Road bridge over the same river valley, which was dismantled a few years ago.

(3)In response to Mr. Sabath's note of 11-5-07, everyone that wants the Boonville Bridge preserved so that people can ooh and ah over it are forgetting some hard truths. First, the Coast Guard doesn't permit unused bridges to be remain over navigable waterways. In fact, they have been demanding that UP remove the Boonville Bridge since at least 1992. There's an interesting filing by UP on the STB's website in May 2005 (a "consummation notice") that contains correspondence from the Coast Guard on this point (as well as other info on the Boonville Bridge) which is well worth reading if you're interested in this subject. Third, it would be very difficult and expensive to restore and operate this bridge for "use". It's a lift bridge, and the bridge has been left in the "up" position for water traffic. To use the bridge, one would either have to make the lift span operational and staff it with a bridge tender, or build a bridge within an bridge to carry an ADA compliant walkway over the raised span. Who is going to pay for this? Fourth, I question whether the bridge could even be left in its current condition indefinitely. It appears to me that the lift span is simply hanging on its lift ropes. Bridges like this are not designed to be left this way for years on end - they are designed to be left down and raised only when necessary. The ropes will eventually have to be replaced. Again, who's going to pay for it? Needless to say, a failure would lead to collapse of the span (recall the former M&STL Keithsburg Bridge, another unused lift span left in the up position, which collapsed into the Mississippi when a fire caused the grease impregnated lift ropes to fail). And finally, this is the railroad's property. I don't see people lining up money in hand to buy the bridge from the railroad.