Most of us, in the United States at least, grew up where the supply of water was so simple. Your house was automatically connected to the city water mains when it was built and for a few dollars a month all the water you needed was supplied at the turn of a tap.
My first home made water supply was out in the Louisiana swamps where average rainfall was more than fifty inches a year. It was a simple matter to build a catch system that caught the rain off the roof. But it was full of crud. A simple little device to catch the first of the rain in a bucket and when the bucket was full it pulled the outlet over to the big cistern and I had a water supply.
Later I moved to the desert and water got a lot more tricky, with rainfall of eight inches a year the rules are different. The biggest projects were a series of about five thousand small enclosed catch basins which were burried in every little dry creek bed to catch what little water there was for birds to drink. Yes, it may sound silly, but that's what the people with the money wanted.
As for this book, I only wish that I had known what contained in it when I started. Everything he says sounds so simple, makes so much sense that I wonder why I had to spend so much time making mistakes that taught me these same things.
If you're going to go play in the water business, either for yourself, or even for a water department read this book first.