Hohokam Irrigation Canals, Pueblo Grande Museum, Phoenix

Source document Quoted word for word from HAER AZ-89. Not written, edited or summarised by this site.

The Hohokam irrigation system in the Salt River Valley, which reached its peak between the years and was the largest prehistoric water supply system in the United States. Only a few sections of Hohokam canals are left in the Salt River Valley due to urban development. The canals at Pueblo Grande are among the best preserved sections remaining. Description: The total length of the Hohokam canals in the Salt River Valley is estimated to be about 150 miles. Some canals were over 30' wide and 10' deep.1 The canals have been abandoned since the fourteenth century, and today only two short sections have been preserved at the Pueblo Grande Museum. These sections are located near the Salt River where water was diverted into them by stones or brush diversion dams.

A cross-sectional excavation of the two canals revealed the south canal to be older and V- shaped. From its lowest level to the present surface, the canal measured 15' and 22' to the top of the bank. The north canal was found to be three times wider than the south canal. It was lined with clay on its bottom and lower sides to prevent seepage in those areas where the canal cut across layers of sand and gravel. History: Over time, the Hohokam developed an extensive network of canals extending over 150 miles in the Salt River Valley, resulting in the largest prehistoric irrigation project in North America. About twenty-two villages and many smaller communities were spread out over this network of canals, with Pueblo Grande as one of the large villages.

Since the Hohokam did not have large earth-moving machinery, construction of these canals was done entirely by hand using stone and 1 Emil W. Haury, Arizona s Ancient Irrigation Builders, Natural History LIV (September HOHOKAM IRRIGATION CANALS HAER No. AZ-89 (Page 2) wood tools. The Hohokam canal builders had a good understanding of the engineering principles involved in canal design. Sometimes they used sedimentation basins to prevent silting of canals. Proper grades were used to pass water through canals without causing erosion of the banks. The Hohokam also made use of storage reservoirs along their canals. Los Muertos, a prehistoric community south of the Salt River, was supplied with water from a reservoir that had a single canal for both its inlet and outlet.

The amount of land irrigated by the Hohokam during any period in their civilization is not known, but experts agree that the entire Salt River Valley system, built over a span of 500 to 700 years, was capable of irrigating acres. Because of attacks from other American Indians, and the fact they had waterlogged their fields with irrigation, the Hohokam abandoned the Salt River Valley by C.E. in order to return to the Gila River.

Source document Quoted word for word from HAER AZ-89. Not written, edited or summarised by this site.

Haury, Emil W. Arizona s Ancient Irrigation Builders. Natural History LIV (September Haury, Emil W. and Helga Teiwes. First Masters of the American Desert; the Hohokam. National Geographic Magazine CXXXI, no. 5 (May Hess, Ralph H. The Beginnings of Irrigation in the U.S. Journal of Political Economy 20 (October Hiser, Donald H., City Archeologist, Pueblo Grande Museum. Interview by the field team, August 6, Hodge, Prehistoric Irrigation in Arizona. American Anthropologist (July Gladwin, Harold S., Emil W. Haury, E.B. Sayles, and Nora Gladwin. Excavations at Snaketown. Material Culture. Tucson: The University of Arizona Press, Schroeder, Albert H. Prehistoric Canals in the Salt River Valley, Arizona. American Antiquity VIII, no. 4 (April Shetbone, Henry C.

A Unique Prehistoric Irrigation Project. Annual Report of the Smithsonian Institution Turney, Omar. Prehistoric Irrigation in Arizona. Phoenix: Arizona State Historian, HOHOKAM IRRIGATION CANALS HAER No. AZ-89 (Page 3) Woodbury, The Hohokam Canals at Pueblo Grande, Arizona. American Antiquity XXVI, no. 2 (October Historians: T. Lindsay Baker and Steve Rae, August 7 and October 22, January 3,

Source document Quoted word for word from HAER AZ-89. Not written, edited or summarised by this site.

The Hohokam Irrigation Canals were inventoried for the Historic American Engineering Record as part of the Southwest Water Resources Project, a joint project with the Texas Tech Water Resources Center. The survey was subsequently published as Water for the Southwest: Historical Survey and Guide to Historic Sites by the American Society of Civil Engineers in September