As I was walking my dog down around Birch Bay I was seeing something close to surface of water. The object was like skipping on the water like a stone as it crossed the bay. It was no more than 200 to 300 feet from me. As it crossed in front of me I thought I saw someone sitting in it driving it like a car. I was so amazed that I stood there dumbfounded as it passed me. I am thinking it was 7 to 10 feet or more in diameter. I thought it was water craft of some kind until it shot up into the air very quickly and out of sight.