Every homeowner dreams of a water feature on their property at least once in a while. But should it be a cement pool for the kids to swim in, or a nature pond with plants and fish? David Pagan Butler said, "Why not both?"
He began with digging up the entire back yard and centered a very deep hole, lined with cement and concrete blocks. But that's just the foundation. It was overlaid with various layers of protection, drainage, and organic materials to bring nature back to the big hole. That's a lot of work, but the result is a swimming hole that will last forever.
Since he constructed this pool ten years ago, Butler has started a business building such ponds and teaching people how to do it. You can read a free 30-page overview of the process here.