It's downright creepy how much natural and man-made stuff there is on the bottom (and sometimes top!) Of that river. The changing tides deposit old stuff in new places all the time. You can see it all at low tide, but it doesn't take long for the incoming tide to bury a lot of nasty stuff a couple inches under the surface, and the growing river makes it hard to pinpoint where obvious stuff you saw earlier will be lurking.

I bob around in the area in question in a pontoon boat quite a bit this time of year. I've bumped into and slid over all kinds of stuff with my feet. So far, nothing too life-threatening, but I've gotten pretty spooked several times. It's easy to let the river's big, slow character lull you to sleep and lose sight of just how dangerous it can be, but anyone who fishes it a lot eventually learns to respect it, most often after a good scare, and in a few unfortunate cases like this one, after a serious accident. Glad to know everyone's alive, and equally glad I'm not nursing a 20-staple leg laceration. As SZ said, "Ouch."