The Wastewater Gardener is an interesting read. The author gives a historical review of "waste" management through the last couple centuries, how the bigger cities developed sewage systems and helped control waterborne illness to indoor plumbing. Through the invention of indoor plumbing, and other uses of our now fresh water system, he has shown the importance of water conservation and how to recycle both black water and gray water to an advantage.
The one downside to this book is there is some technical information the author shares, which is not a bad thing, but not being a scientist, took a bit to get through. The majority of his "biospheres" that have been created have been done in the south and in the southern hemisphere. I would be interested if this works as well in northern areas.
This is something I would definitely recommend to homesteaders and others looking into sustainable living.
***I received this book free from the publisher through a Goodreads giveaway****