D.B. Knowles 1955 <p>The objective of the Ground Water Branch is to evaluate the occurrence, availability, and quality of ground water. &nbsp;The science of ground-water hydrology is applied toward attaining that goal. &nbsp;Although many ground-water investigations are of a qualitative nature, quantitative studies are necessarily an integral component of the complete evaluation of occurrence and availability. &nbsp;The worth of an aquifer as a fully developed source of water depends largely on two inherent characteristics: its ability to store, and its ability to transmit water. &nbsp;Furthermore, quantitative knowledge of these characteristics facilitates measurement of hydrologic entities such as recharge, leakage, evapotranspiration, etc. &nbsp;It is recognized that these two characteristics, referred to as the coefficients of storage and transmissibility, generally provide the very foundation on which quantitative studies are constructed. &nbsp;Within the science of ground-water hydrology, ground-water hydraulics methods are applied to determine these constats from field data.</p> application/pdf 10.3133/ofr5585 en U.S. Geological Survey Ground-water hydraulics - A summary of lectures presented by John G. Ferris at short courses conducted by the Ground Water Branch, part 1, Theory reports