Hey does drinking water increase cum
Some people say it does, but I'm pretty sure it is a myth. Put it this way - I don't think you would see a decline in semen volume unless you were extremely dehydrated (almost ready to die from dehydration).
Excess water that is in your bloodsteam ends up going to the kidneys for processing, then passed to your bladder. This process should have no effect on the semen producing glands such as the prostate and seminal vesicles.