On days when it’s very cold, the Chicago River does occasionally freeze over. If the ice is at all thick, they send a big ice-breaking boat up and down the river periodically to avoid damage to all of the other vessels that pass through.
Spotted this just after dusk as I left the office a few weeks ago. Taking long exposures on this bridge is particularly tricky though – all of the bridges over the river are movable (technically, most are “bascule” bridges). What this means to me as a photographer is that there is a gap in the middle that is not physically stabilized – if you stand in the middle when anything goes across the bridge, the whole structure acts a little like a diving board. Stabilizing the camera against the railing (or even with a tripod) is fairly useless if a double-long bus goes by just as your shutter finger comes down.
Which doesn’t really get too frustrating until after the fourth or fifth time. In a row. Needless to say, there were a few throw-aways from this set… here’s the best of the bunch: