Established in 1879, the USGS has a distinguished history of leadership serving the nation by providing scientific data to describe and understand Earth systems and by providing unbiased assessments to facilitate management of the nation’s natural resources. Since its beginning, the USGS has been the primary federal agency responsible for assessing the quantity and quality of the nation’s surface water and groundwater. Hydrologic research and hydrologic data collection and analyses are implemented through the USGS Water Resources Discipline, one of four broad earth science Disciplines around which the USGS is organized (Biology, Geography, Geology, and Water, and a directorate for geospatial information). At present, the Water Resources Discipline has a workforce of about 3,300 water scientists and technicians working in 181 offices throughout the country. The USGS maintains Water Science Center offices (or integrated Science Centers offices) in every state and three major regional research offices (western, central, and eastern). The Water Resources Discipline has evolved throughout the history of the agency, yet Water’s mission has remained constant—“to provide reliable, impartial, timely information needed to understand the nation’s water resources.”
Because the USGS is a science agency with no regulatory or management responsibilities, the Water Resources Discipline is recognized as a source of unbiased scientific information and hydrologic data. USGS research, studies, and data are used by other federal agencies; state, local, and tribal governments; the private sector; and academia as a basis for a wide range of water resources research and water planning and management decisions, including: water infrastructure design and maintenance, flood monitoring and emergency notification, drought monitoring, water rights administration, water quality management, and other related services. The USGS is also a trusted source of hydrologic data and science for resolving inter-jurisdictional disputes, such as water disputes between states.
The USGS carries out its water resources mission through several individual programs (Box 1-2) that cumulatively support the nation's hydrologic data network and provide hydrologic assessments at the national, regional, state, and local scale. USGS data and information from these programs are integrated into the National Hydrologic Information System and provided freely to all parties via the internet. These data are used by a wide audience for many purposes and serve as an important national resource of hydrologic information.
Most of these WRD programs are familiar to water resources interested parties; most are also identified as budget lines for the agency. To