The Operation and Evolution of an Irrigation System: The East Papago Canal Study

Archaeological investigations sponsored by the Arizona Department of Transportation (ADOT) were conducted by Soil Systems, Inc. (SSI) at several sites within the East Papago Freeway corridor, including El Caserío (AZ T:12:49(ASM)), La Lomita (AZ U:9:67(ASM)), and La Lomita Pequeña (AZ U:9:66(ASM)). During the investigation of these sites, a significant number of canal alignments were encountered, prompting the sponsoring of the East Papago Canal Study by ADOT.
Canal System 2, traversed by the East Papago Freeway corridor, consisted of prehistoric main canals that headed on the Salt River, as well as a variety of other types of canals (distribution, cross-cut, branch, and field laterals). For this project, these canals were examined in terms of morphology (length, gradient, width-to depth ratio, discharge capacity) and chronology (continuity of use, reuse, abandonment sequences) in order to reconstruct how the system operated. Reconstruction of Canal System 2 also involved the examination of canal cross sections from other projects in the vicinity. This provided information on distant segments of the same canal, thus allowing for a more accurate correlation than had been previously possible. In addition, a series of maps of Canal System 2 has been generated from the data collected by this project. These maps are available at ADOT, Arizona State Museum, Pueblo Grande Museum, and the State Historic Preservation Office.