There were thousands of slips and boats damaged a couple of years ago with a similar winter storm at Lake of the Ozarks. Insurance claims were a real mess, as some policies did not cover certain issues, and of course many needed "riders" that they did not have. At the very least, it is a good thing to remind everybody to check policies. Our covered slip was covered by one insurance, and the boat (it was totalled) was covered by another insurance company. We were much luckier than alot of folks. There were several 40+ foot crusiers that sunk with all of the weight on them.
Good luck with your process.