This atlas was prepared to meet the need for information on the areal distribution, quantity, and availability of ground water in the lower Colorado River region, an area of about 140,000 square miles in parts of Arizona, Nevada, New Mexico, and Utah. The lower Colorado River region is divided into three water provinces--the Basin and Range lowlands province, the Plateau uplands province, and the Central highlands province. The annual precipitation in the region ranges from 3 inches near Yuma, Ariz., to as much as 35 inches on the highest peaks, such as those of the Chiricahua Mountains in Arizona. The precipitation in the lowlands ranges from about 10 to 12 inches per year. In the Basin and Range lowlands the hydraulic conductivity of the aquifers can be as much as 130 feet per day. In the Plateau uplands province most of the groundwater occurs in three multiple-aquifer systems. For the most part, the multiple-aquifer systems do not transmit water readily, and the hydraulic conductivity generally is less than 1.3 feet per day. The Central highlands province is a mountainous area that separates the Plateau uplands from the Basin and Range lowlands in most of the lower Colorado region. The principal discharge area for ground water in the highlands occurs along the base of the Mogollon Rim. (Woodard-USGS)
Additional Publication Details
USGS Numbered Series
Preliminary maps showing ground-water resources in the Lower Colorado River region, Arizona, Nevada, New Mexico, and Utah
4 maps on 3 sheets :col. ;105 x 148 cm. or smaller fold. in envelope 30 x 24 cm.