Drinking alot of water helps not only for getting weed out of the system but for detoxing any kind of poison in the body.But for the sake of water poisoning watch your water intake, too much could be dangerous for the body.
For the sake of reference check out this article on Water Poisoning on Wikipedia. Stay Clear of too much water.
Water can be considered a poison when over-consumed just like any other substance. The recommendation from the medical field is to drink at least 1 to 2 liters per day depending upon body mass. Water intoxication would only occur at levels far higher than that.
