Water is always an issue in the Book Cliffs. I wouldnt say that is enough of a factor to push deer out of the area though. I think the herd is there to stay. Of course the abundance will positively affect horn growth, but it will also negatively affect your chances of finding deer. There are plenty of places in the Books that hold water and the deer know where they are. In times when water is scarce, they seem to stay near these holes. When there is a lot of water out there, they dont feel as committed to their usual water spots.
I hunted there in 2002 and 2005 and shot both of my deer near their watering holes. My 05 buck was seen at the same water hole twice in 12 hours. We were tipped on to a very large buck that was at this water hole, but after several occasions of watching, we never saw him return, though his tracks were definitely there before. I think he just moved on to another water source. I have seen the smaller/medium size bucks commit to water holes, while it appears the the larger bucks are more prone to roam around.
Good luck on your draw out there. If you get a tag, let me know and Ill do what I can to fill you in on the area.
-Travis