I've seen it on the St.Croix many years ago. Marina operators are worried about the water suddenly coming up at night and floating the boats off of the jack stands and other supports. No problem if someone is around to put in the plugs and put the boat into a slip. If no one is around however................ well you get the picture. Other marinas will follow suit if the water continues to rise. This one good thing about keeping the boat in the water, at the slip all year long.