Water...

Wondering at what point a person can consume too much water and begin retain it (or it simply shows up as a gain on the scales)??? I drink a typical 8-14 glasses a day...but noticed I gained ~ 1# the day after my bowling league (at which I drank 2 pitchers of water). Granted it was gone 2 days later, but wondering at what point a body begins to retain? 120 ounces? 160 ounces? Anyone have any idea???