Yes that is a lot of water Tbar. (I watched the video now that it is fixed).
I was a little paranoid about my dock and set the bottom of the steel truss about 6" above where the emergency overflow would start to flow water. Then the top of the dock is another 10" above that. It would be nice at times if my dock was a little closer to the water, but I have a floating portion on the end for that.
But I probably don't have near the watershed area running into my pond as you do. It may not be common, but we can get a foot of rain in 24 hours "here" and it happens at least every few years. So we are kind of used to seasonal flooding. We don't like it, but are somewhat used to it.
