Maps showing ground-water conditions in the eastern part of the Salt River Valley area, Maricopa and Pinal counties, Arizona, 1976

In 1976 about 1.68 million acre-feet of ground water was pumped in the Salt River Valley, Ariz. Since 1923, more than 73 million acre-feet has been withdrawn, which has resulted in a general decline in water levels. Water levels in the eastern part of the Salt River Valley area have declined as much as 420 feet. Information on the maps includes altitude of the water level, depth to water, change in water level (1923-76), and irrigated area. Hydrographs of the water level in selected wells, a table of historical pumpage, and a brief discussion of the chemical quality of the ground water are included also. (Woodard-USGS)