I just saw this thread, I hit this about a year ago, the Knot draws just short of 6', I don't remember the date but I do remember the water was pretty low. No damage but a quick hard hit, there is a mention in the 2018 Waterway Guide about a "unmarked wreck of an old iron barge just south of #5" on page 707. It's on the south side of the channel, but definitely in the channel, as I recall.