Water issues dominate the thinking and efforts of agriculturists in dry areas, where what little rain that falls commonly occurs in intense storms and provides only short-term benefits to the growing crops. By encouraging and collecting runoff, water harvesting increases and extends the availability of water for crops and reduces risk. The basic principle is to harvest the water from one area of land to support cropping on another. The water is also used for livestock and human consumption.

Eight chapters of this book describe the principles and practices of rainwater harvesting in dry areas, covering a wide range of water harvesting systems, from those developed by ancient societies to present-day systems, which can now be designed using remote sensing and modern tools such as Google maps. Throughout the text are line drawings and photographs, which are particularly well done, as are the additional 25 pages of colour plates. The last two chapters, which address associated socio-economic and environmental aspects of rainwater harvesting, complement the strong practical engineering focus of the book.

Readers will find this book to be a valuable source on rainwater harvesting. Its appeal could have been broadened by discussing in considerably more detail topics such as the geographic scope and agroecological definition of ‘dry areas’; the methods used to distribute water to crops; and the potential role of crop simulation and risk analysis in managing water supplementation, which is an increasingly pertinent issue as the climate changes.