Since no one is being quantitative, here's a medical source: https://my.clevelandclinic.org/health/diseases/water-intoxication https://my.clevelandclinic.org/h

Since no one is being quantitative, here's a medical source: https://my.clevelandclinic.org/health/diseases/water-intoxication https://my.clevelandclinic.org/health/diseases/water-intoxic... > In some people, water intoxication symptoms can develop after drinking about a gallon (3 to 4 liters) of water over an hour or two. > More than 32 ounces (about a liter) of water per hour is probably too much.