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. USGS carries out its water resources mission through several individual programs spread throughout the agency (Box 1-1) that cumulatively support the nation’s hydrologic data network and provide hydrologic assessments at the national, regional, state, and local scale. One of these is the National Water-Quality Assessment (NAWQA) program.
NAWQA was designed and tested in the late 1980s and was implemented at full scale in 1991 to assess historical and current water quality and future water quality scenarios in representative river basins and aquifers across the country. NAWQA’s primary objectives are to assess the status of the nation’s groundwater and surface-water resources; evaluate trends in water quality over time; and understand how and to what degree natural and anthropogenic activities affect water quality. Taken together, NAWQA’s goal is to provide a national synthesis of the interaction between natural factors, human activities, and water-quality conditions to define factors that affect national water resources.
NAWQA’s goals are achieved through a design that stresses long-term, standardized collection and interpretation of physical, chemical, and biological water-quality data. NAWQA is not a research program per se; it uses known tools and understanding of processes to probe relevant water-quality topics. Research conducted by USGS’s National Research Program and the Toxic Substances Hydrology Program, for example, helps define NAWQA methodologies and topics for the future, but NAWQA does not employ untested methods for probing water quality. Perennial water-quality data collection and sequential assessments in river basins and aquifers as well as regional and national syntheses are key features of the NAWQA program. These activities not only define the status of and trends in water quality, but they also build an evolving understanding of regional and national water quality achieved through careful analysis and interpretation of these long-term water resource data sets.
NAWQA’s first decade (Cycle 1, 1991-2001) focused on a baseline assessment of status of the nation’s water-quality conditions. The second decade (Cycle 2, 2002 to the present) focused on a more broad-based water-quality assessment, building on the Cycle 1 status monitoring and identifying trends in water quality. Now, USGS scientists are planning for NAWQA’s third decade of water-quality assessment (Cycle 3, 2013-2023) and approached the National Research Council’s (NRC’s) Water Science and Technology Board (WSTB) for perspective on past accomplishments as well as the current and future design and scope of the program. The NRC