drinking too much water?

Question
My boyfriend and I rescued our black lab mix, Hunter last June. He is 8 months old now and getting HUGE- which is fine, my boyfriend always wanted a big dog. I have 2 questions. We don't know what hes mixed with, mostly lab definitely, but I was wondering if you could tell me when most dogs stop growing? lol because hes kind of out growing our apartment and slams into walls and makes a lot of noise now. Hes actually not TOO big right now, probably about 40lbs, but I just wanted to know if you had any idea, or if you know of another expert I should ask. Another thing you should know about Hunter, him and his entire litter were found in the woods and were extremely underweight and malnourished. Hunter was in the worst shape with terrible mange and was also the runt. Anyway, ever since we got him, he hoards water like hes never going to have any ever again. When we take him to the dog park he will stand by the water bowls and drink continuously until we tell him to get away. We
saw this same behavior with food, but he has slowed down a lot with his eating. Will he continue to be a camel due to his early life in the woods? Or do you think it could be a more serious medical issue that is unrelated? Thanks so much, I hope you can help. Please let me know if these questions are outside your expertise so I can ask someone else. Thanks so much for your time!


Answer
At 8 months, his growth may be slowing, and he will level off around 50 pounds at a year old.  They are not consistent about that.  He could keep on growing fairly rapidly and turn out to be closer to 70 pounds.  

I think I have seen the water hoarding.  Sometimes when we have guests, it turns into competitive water drinking, each puppy wanting to make sure it gets its share.  Sometimes we take the water bowl up.