Yup, better know where you're going especially on some rivers.
This was a back channel off the Upper Kenai River in Alaska.
A group of 5 borrowed a 16' pontoon to float the river and went down a back channel that is known to be almost impassable.
The raft actually stopped upright when it hit the sweeper. It wasn't until one of them got off onto the log when things went bad in a hurry. All went into the water and 2 older gentlemen (over 80) nearly drowned.
My buddy and I rescued the raft so that the owner could retrieve it.