The ancient Hohokam inhabitants of the Salt River Valley constructed an extensive system of irrigation canals that allowed them to live and prosper in the arid desert for a thousand years, a remarkable achievement for a pre-industrial society. More than a century of research by archaeologists and geomorphologists has revealed that Hohokam farmers built the largest network of canals in the New World, with more than 1000 miles of canals constructed between AD 500 and 1450. Dr. Bostwick will talk about the evolution of the canal systems, how they were engineered and maintained, and challenges the Hohokam had to overcome such as floods and droughts. In addition, ideas will be presented about how the Hohokam organized themselves in order to best manage their complex irrigation systems. Illustrations, graphs, and photographs of canals excavated by archaeologists in the Salt River Valley will be shown to help explain the amazing ingenuity and skills of the Hohokam canal builders.