Ground Water Availability in the United States

Ground water is among the Nation's most important natural resources. Large-scale development of ground-water resources with accompanying declines in ground-water levels and other effects of pumping has led to concerns about the future availability of ground water to meet domestic, agricultural, industrial, and environmental needs. The challenges in determining ground-water availability are many.  One of these challenges is obtaining the necessary data of ground-water levels, ground-water quality, and aquifer properties and boundary conditions.  These data are fundamental pieces in the larger puzzle of ground-water availability at any scale.

This presentation examines what is known about the Nation's ground-water availability and outlines a program of study by the U.S. Geological Survey Ground-Water Resources Program to improve our understanding of ground-water availability in major aquifers across the Nation. Water availability is a function not only of the quantity and quality of water in a basin or aquifer system but also the physical structures, laws, regulations, and socioeconomic factors that control its demand and use. The approach of the U.S. Geological Survey effort focuses on determining the quantity and quality of the ground water in regional aquifer systems and is designed to provide useful objective regional information for use by the State and local agencies who manage the ground-water resources.  These regional evaluations are only as good as the data used as the foundation of the evaluation.  Efforts like the National Ground-Water Monitoring Network proposed by the federal Advisory Committee on Water Information Subcommittee on Ground Water would provide valuable additional data, and thus may improve nationwide estimates of ground-water availability.  This regional information and advances in scientific methods will provide fundamental information needed for a national assessment of ground-water availability.