The Impact of Flooding on Hohokam Canal Irrigation Agriculture

​By Kyle Woodson

Kyle Woodson is an archaeologist who has conducted extensive primary investigations of the Gila River Hohokam (near modern-day Phoenix, Arizona). In Chapter 6, he investigates an important question, that of the relationship of river behavior and Hohokam irrigation. A common claim in studies of Hohokam irrigation agriculture is that flooding events were problematic or even disastrous for canal system infrastructure and for irrigators. The sources for these hypotheses include records of historic floods in the Phoenix Basin, reconstructed streamflows based on tree-ring research, and the geological history of river environments. This chapter examines what we do and do not know about floods, the effects of flooding on the landscape and on canal irrigation agriculture, and the human responses to flood impacts. Woodson describes the reasons why we need to know more about flooding and flood impacts on prehistoric irrigators, and he outlines a method for learning more about these topics. He also presents the types of evidence that can be used to test hypotheses about the impact of flooding on Hohokam irrigation agriculture.