Having paddled the Okefenokee swamp a time, I will tell you not to be worried. I think our gator count for day one was like 67. Much of our time paddling was through canoe "trails" which are 3 foot wide cuts in the swamp, that aren't very deep. If you are the lead canoe through those, and you accidentally hit one on the head with your paddle, he doesn't like it. Lets just say I was lead man in lead canoe, and his head looked a lot like a log until it moved. And, it didn't move until after I hit it (thinking it was a log I was going to push off of). Then, it about got into the boat. One claw was completely over the side, and both my scoutmaster (backseat of said canoe) and I thought he was coming in. Apparently, he was just trying to get away. Scared the living daylights out of me.
Anyway, in your case, don't stand right at the waters edge. 3 feet will be more than plenty, and don't mess with a sleeping gator on the shore. Those are the ones to be afraid of. Give them some space.