"lose water weight"
no, one cannot lose "water weight" by increasing water intake. the only natural way to lose water-weight is through exercise, and then as soon as one goes through the recovery phase, post-workout, one drinks water (and takes in electrolytes) and then the water-weight is regained.
trying to permanently keep off water-weight (aka live dehydrated) will cause severe health problems almost immediately, and in extreme persisting cases, even death.
weight fluctuates naturally, and this is due to many factors, but the main one is water-weight. it is nothing to fluctuate anywhere from 5-10 lbs.(respective to bodyweight) on a weekly basis. if one is seeking, longterm, to lose a significant amount of weight outside of this range, then a different approach must be taken.