I also consume about 6 liters of water during the working hours, so there ya go.
Unless you have a very physical occupation, this may be too much H2O

You Can Drink Too Much Water
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
I also consume about 6 liters of water during the working hours, so there ya go.
I think flushing the wetsuit depends on the suit. I have a couple of old ones that flush well, and a new one that will not. It is tighter and firmer.... And pee-free, so far!
Basically the only way to achieve that (as the article also kinda states) is to only drink excessive ammounts of water, without eating or taking mineral additions..