Yes it will but the amount of water is not the key but rather how much you pee out although drinking to much water over a short period of time is harmful
Depending on how often you smoke and for how long you have been smoking weed has to clear itself out of your system. Water can't hurt but if your asking this question for drug testing no way you will fail.
NO! It will not! It will stay in your body for approx. 30 days. Just don't do drugs, ok?