This map, produced in 1891 by the United States Department of Agriculture’s Office of Irrigation Inquiry, is titled Map Illustrating the Progress of Irrigation Within the Arid and Semi-Arid Region of the United States West of the 97th Degree of Longitude West from Greenwich. It reflects the federal government’s efforts to document and assess irrigation practices in the western United States during the late 19th century, a time when water management was vital for agricultural and economic development in the arid West.
The map covers the regions west of the 97th meridian, including states such as Arizona, California, Nevada, Utah, Colorado, and parts of Oregon, Washington, and Texas. It extends north to the Canadian border and south to the U.S.-Mexico border. Geographic features such as rivers, mountain ranges, and settlements are meticulously detailed, while irrigated areas are shaded in blue to highlight the extent of water management and cultivation efforts.
Accompanying the map is a statistical table that provides comprehensive data on irrigation and water use by state and territory. This includes figures on the acreage of land "under ditch" (prepared for irrigation), land actively cultivated with irrigation, and the number of artesian wells in operation. For example, the table notes substantial irrigation progress in California, Utah, and Colorado, reflecting significant infrastructure development during this period. The text also emphasizes the experimental and practical challenges of tapping underground water sources and expanding irrigation systems.
The map was prepared by Frank Blaisdell, a civil engineer, as part of the federal government’s broader initiative to transform arid landscapes into productive farmland. This initiative included not only mapping but also promoting technological innovations, such as artesian wells, and creating policies to encourage settlement and agricultural development in areas with scarce rainfall. The accompanying notes further contextualize the challenges and achievements of irrigation in these regions, offering a snapshot of how water management was evolving.