If he dreams of drinking all the water it means his life span is completed; he should now prepare for the hereafter.
If he drinks the water partially it means he still has a number of years to live.
The same interpretation is given if, instead of water, the contents of the bowl or dish is thareed*.
(*Thareed: Pieces of bread steeped in broth)
What Does Water In A Dish Or Bowl Mean In Dream?