I went to the Gilford tax map and the amount of land on the water side of route 11 that the Park actually uses is only 23 acres. According to the state website the land on the opposite side would be very difficult to develop for campsites. Unfortunately the size of the map file is to large to post.
Here is a link for the map. You can zoom in to it and it will give acres.
http://www.mapsonline.net/gilfordnh/