The water thing is the reason people die from taking ecstacy normally in England. They drink so much that they get water poisoning.

Smoking cannabis heavily wont do anything though. You'd never be able to overdose on it, no one can, and it wont cause any problems with breathing because the THC dilates the bronical tubes and the whole throat. That's why its a good asthma cure, but oh no, the government wont give it out because its a "drug" ... My fucking ass, synthetic drugs kill more each yeah than the illegal ones.