Ice Out Dock lost

[winterh]

I don't think your loss of power would have made much difference. It is my understanding that the ice can attack your dock in two ways and a bubbler only protects it from one. When the ice freezes solid around your fixed posts it can move them up, down sideways...with the movement of the ice. A bubbler keeps the ice from forming and moving your posts.
The second cause of damage is wind driven icebergs moving in the spring. These can be huge and weigh thousands of tons. There is pretty much nothing that can stop them and your dock is at the mercy of the wind direction. By the looks and timing of your damage it looks like it got hit by a sheet of ice. Even if your bubbler was going 24/7 it would not have made much difference.
I ran my bubbler all winter a few years back. I thought I was in the clear when an ice flow took out my dock just days before ice out. it was painful to watch this sheet of ice come out of nowhere and destroy everything in its path.