Hey FRED,
It used to happen all of the time, but with global warming an all this will probably be the last time... :lol:
No, really, it freezes up about once every four or five year. This year is a lot worst than usual. Most of the time we just have ice flows coming down river. There is a dam at Alton and its not uncommon to have a build-up above the dam, but the "channel" is usually open for the barges. This year they have had to close the locks a time or two to work the ice away from the lock so they will work properly.
Actually, since it usually doesn't freeze solid like this, the Alton area has become to be know as the Bald Eagle capital from late Dec. through Feb. every year. It easy to see dozens of them "fishing" along the Mississippi on a clear day. Some of them nest along the bluffs and stay here year long.