Water-resources investigations of the U.S. Geological Survey include the collection of water-quality data on the chemical and physical characteristics of surface and ground-water supplies of the Nation. These data for the 1966 water year for the quality of surface waters in Arizona are presented in this report. The data were collected by the Water Resources Division of the U.S. Geological Survey under the di rection of H. M. Babcock, district chief.
Water-quality information is presented for chemical quality, fluvial sediment, and water temperatures. The chemical quality includes concentrations of individual dissolved constituents and certain properties or characteristics, such as hardness, sodium-adsorption ratio, specific conductance, and pH. Fluvial-sediment information is given for suspended-sediment discharges and concentrations and for particle-size distribution of suspended sediment and bed material. Water temperature data represent once-daily observations, except for stations where a continuous temperature recorder furnishes information from which daily minimums and maximums are obtained.
The Geological Survey published the annual series of water-supply papers, "Quality of Surface Waters of the Unit ed States," from 1941 through 1963, which contained the chemical-quality, temperature, and suspended sediment data of the water. Each volume covered an area whose boundaries coincided with those of certain natural drainage areas. The records for Arizona are contained in part 9 of the water-supply paper series. (See table, p. 12.) These publications are available in most public libraries. Beginning with the 1964 water year, water quality records for surface water obtained by the Geological Survey have been published in a new series of annual releases on a State boundary basis. This report is primarily for local and immediate use, and its distribution is limited. The records will be published in Geological Survey water-supply papers at 5-year intervals. The first compilation will cover only the 1964 and 1965 water years.
