Excerpts from the report: The San Juan River Basin is located in the Four Corners area of Arizona, Colorado, New Mexico and Utah. It includes 8 percent of New Mexico, 5.5 percent of Colorado, 5.1 percent of Utah, and 4.5 percent of Arizona. The basin extends approximately 250 miles east and west, and 160 miles north and south. It is entirely within the Upper Colorado Region and drains an area of 24,945 square miles (15,965,200 acres) or about one-fourth of this region. The New Mexico portion comprises 39 percent of the basin and includes nearly all of San Juan County and parts of Rio Arriba, Sandoval, and McKinley counties. Slightly more than 23 percent of the basin is within Colorado. Included are La Plata, most of Archuleta, Montezuma and San Juan, and parts of Dolores, Hinsdale and Mineral counties. Very small areas of San Miguel, Rio Grande, and Conejos counties are also included in the basin. Arizona has a little over 20 percent of the area of the basin which consists of parts of Apache, Navajo and Coconino counties. The remaining portion of the basin (about 17 percent) is in San Juan county, Utah. The northern and northwestern boundary of the basin is defined by the Gunnison, Dolores, and Colorado River divides. The eastern and southeastern boundary follows the Continental Divide. The southern and southwestern boundary is the divide of the East and West Puercos and the Little Colorado Rivers. The extreme western boundary is the divide of the Colorado River. This report presents information concerning water and related land resources of the San Juan River Basin located in the "Four Corners" area of Arizona, Colorado, New Mexico and Utah. The broad objective of the study area is the collection and development of information on water and related land resource use and management, with particular regard to multiple use. This information will provide a basis for effective coordination of USDA programs for watershed protection, flood prevention, agricultural water management, recreation, fish and wildlife development, municipal and industrial water development, and associated national forest administration, with the related activities of local, state, and other federal agencies
