How much water would one have to drink before you overdose on it?

DEPENDS HOW FAST. It is not really how much water you drink, but rather how fast you drink it. Normally, a person requires about 3 quarts of water each day where most of it is from food so 8-12, 8oz glasses a day is the recommended intake in addition, the average healthy person should ingest no more than 8 oz. (240ml) in roughly an hour giving the body adequate time to absorb it. Max appeares to be < 1liter/hour.