What I find most interesting is that the city actually gave him a permit originally to build a 30 ft water tower! I guess that's only as big as a three-story building, but still, he must be pretty far out in the country to get something like that approved in the first place.
West Lake Hills is one of the more "elite" areas on the outskirts of Austin. Lots of huge lots with multi million dollar estates and homes. I don't know all the restrictions on construction there, as I live 35 - 40 miles away by road.
He needs to make it look like the water tower at the Lady Bird Johnson Wild Flower Center:
http://www.wildflower.org/
(the stone tower in the center is the cistern)