As a kidney stone sufferer.....another HUGE reason to drink alot of water is the benefit of flushing your kidneys of excess minerals and toxins.
All of the vitamins and many of the medications we take are filtered through the kidneys.
If an adequate amount of water is not taken in....the leftover "junk" in our kidneys can crystalize and form kidney stones.
Since there is a correlation between UC and kidney stones - I think it's another good reason to increase your water intake.
My urologist has told me I should drink a minimum of 8 glasses of water per day - spread out over the full day to keeps the kidneys well hydrated
As someone who does not like the taste of plain water.... I have taken to loving Propel and Vitamin Water. I usually do 50% plain water and 50% flavored water.