This data set consists of the administrative hydrographic area (HA) boundaries for Nevada at 1:750,000-scale and estimates of natural recharge, artificial recharge, pumpage, and net ground-water flow for each basin where the information is available. Formal hydrographic areas in Nevada were delineated systematically by the U.S. Geological Survey and Nevada Department of Conservation and Natural Resources, Division of Water Resources (NDWR) in the late 1960's (Rush, 1968; Cardinalli and others, 1968) for scientific and administrative purposes. The official hydrographic area names, numbers, and geographic boundaries continue to be used in U.S. Geological Survey scientific reports and NDWR administrative activities.
Although the boundary lines between hydrographic areas generally coincide with true topographic basin divides, some of the lines are arbitrary divisions that have no topographic control. The pumpage, recharge, and interbasin flow estimates were derived from a variety of sources and methods. The data were tabulated and published by Lopes and Evetts in 2004.

References Cited

Cardinalli, J.L., Roach, L.M., Rush, F.E., and Vasey, B.J., comps., 1968, State of Nevada hydrographic areas: Nevada Department of Conservation and Natural Resources, Division of Water Resources map, scale 1:500,000.

Lopes, T.J. and Evetts, D.M., 2004, Ground-water pumpage and artificial recharge for 2000 and average annual natural recharge and inter-basin flow by hydrographic area:
U.S. Geological Survey Scientific Investigations Report 2004-5239, 81 p.

Rush, F.E., 1968, Index to hydrographic areas in Nevada:
Nevada Department of Conservation and Natural Resources,
Division of Water Resources, Information Report 6, 38 p.

Rush, F.E., 1974, Static ground water levels of Nevada: Nevada Department of Conservation and Natural Resources,
Division of Water Resources map, 1 sheet, scale 1:750,000.