Julia A. Huff 2004 The U.S. Geological Survey, Water Resources, in cooperation with Federal, State, and local agencies, obtains a large amount of data pertaining to the groundwater resources of California each water year (October 1?September 30). These data constitute a valuable database for developing an improved understanding of the water resources of the State. Beginning with the 1985 water year and continuing through 1993, these data were published in a report series entitled ?Water Resources Data for California, Volume 5. Ground-Water Data.? Prior to the introduction of this series, historical ground-water information was published in U.S. Geological Survey Water-Supply Papers. application/pdf 10.3133/fs20043061 en Availability Of Ground-Water Data For California, Water Year 2003 reports