I was prairie dog hunting on a ranch in S. Dakota, and I had to cross a smallish river each day to get to the best dog towns. The water level is up more than usual, and on the last evening, crossing the river for the last time, I swamped it! Not a good feeling. I started across in the same spot, and everything seemed fine at first. Then I noticed the water was getting deeper and running faster than it had been that morning. Before I could do anything about it the wheeler started tipping to it's left side. Now, this water is only about 2 feet deep normally. Well, I threw my left leg down to stabilize it, but no deal. My feet never touched bottom. So, the wheeler and me gets tipped over and starts going down river. I quickly regain my footing and bring it to a rest. I still don't know exactly what happened, but I did notice that the current was washing the gravel (on the bottom of the river) away. I think there may have been a soft spot there because it sure got A LOT deeper in a hurry.
I'll skip the rest of the details, but I'll add these last two items: always have the necessary tools with you when you know you're going to be going through water. Tools like a wrench to pull the spark plug. I stupidly didn't think of that. I was alone that time and had to walk 6 miles (roundtrip) back to camp. And then I ended up having to change out all the fluids. Sucked!!!!!