Bob
My club in Adelaide has a couple of large dams built 50 years ago. One of the dam walls needed rebuilding the other year, at a cost of about $80,000. It provides perhaps three weeks water for the course. The main dam provides perhaps seven weeks water. This is in an area with heavy winter ainfall, but also in an area where it might not rain at all for a couple of months at all, and irrigation is needed for six months of every year no matter what.
The main water source is bores, which probably involves about $10,000 a year in relining costs, plus about $15,000 in electricity for water extraction costs. The Government has talked about charging for capture of surface water in the dams, and for extracting the bore water, but it hasn't happened yet. The club is limited with the water quantities that are extracted, but this is adequate for responsible irrigation of the whole course.
Water access has been the key asset for this particluar regular club, and has differentiated it from its neighbouring competitors for membership and in course set-up. Pre 2000, it was a very wet course!
The wtare bills you are talking about exceed the annual income of my club!
James B