The 1893 rebuild (which recently was lost) was a George S. Morison project. HAER #NE-2 has a section on the bridge as well as a nice set of drawings of a number of Morison rail bridges.
Saturday, Jan. 29 demolition operations were taking place on this bridge. Apparently something went wrong and there was an unplanned explosion. No injuries were reported but the BNSF line was closed for a few hours because of it. The Amtrak California Zephyr was one train which was detoured.
Photos of work on the new vertical lift span on the BNSF Burlington Mississippi River bridge.
Answered my own question. Looks like BNSF's replacing the bridge's approach spans, and replacement of the swing span with a lift span is in the works too.
I wonder what type of span they’re going to replace it with? IIRC, an all-new rail bridge across the upper Mississippi hasn’t been built since the early 1960s, and most of the other low-clearance bridges they simply replaced the swing span with a lift span.
Six span pin-connected Whipple truss bridges plus a swing span from the 1800s? Boring... these are a dime a dozen! Must be hundreds of these around... What's that you say, you want me to list some of the other examples? Sorry, I can't think of any right now... but there must be hundreds more, right? That being the case, LETS TEAR THEM ALL DOWN NOW!!!!
Alright, dripping sarcasm aside, BNSF Railroad with the cooperation and support of our wonderful history loving Coast Guard, is beginning project to demolish and replace the Whipple truss spans of this bridge. And since we live in the 21st Century where the only thing we recycle is Coca Cola bottles, I doubt the Whipple truss spans will be moved onto local roads or non-motorized trails as was done in decades past.