They are unknown but they cover an area of more than one million hectares, which is close to 10% of all irrigated land in Pakistan: spate irrigation systems. Also called 'rod kohi' 'sailaba' or 'nai' in different parts of the country. Dependent on making the most out of short duration floods. They embody a unique and ancient culture of water sharing.
This book describes for the very first time these special systems and the societies they have given rise to.