Person parks boat on lake in front of my property?

I own waterfront property on a lake and it is only a small parcel. My neighbor has a semi-large boat parked next to his deck that sits at an angle so that it is blocking the water directly in front of about 1/4 to 1/2 of my property that touches the water. I used to use that land to put my own boat in and out of the water but can no longer do that because his huge boat is floating in the way. Is there some kind of law that says you can't do that? Do I own the rights to use the water directly in front of my property? Help, this is so frustrating!