I was fishing above little hole one day and low and behold here comes an oar floating by so I pick it up and put it on shore. A bit later here comes an overloaded canoe towing half a canoe behind it. I gave them their oar back.
Difficult no but there are definitely things you need to be aware of that can wrap or dump a canoe pretty easily depending on your skills and stability/agility of your canoe. This particular group had wrapped on the rock in Mother-in-Law that eats quite a few boats every year. Just do your research and you should be fine.
We floated the next day and sure enough that rock was colored bright canoe red and I think it stayed that way for some time after.