National Water-Quality Assessment Program - cycle II regional assessments of aquifers

Abstract

U.S. Geological Survey Fact Sheet 2005-3013 May 2005 Printed on recycled paper In the second decade (or “Cycle II”) of the U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) Program, a major focus is on regional assessments of ground-water quality conditions and trends. The assessments will evaluate those conditions and trends in 19 aquifers, most of which underlie multiple States (see map inside). These regional ground-water assessments will build on NAWQA findings from 1991 to 2001 (“Cycle I”) in 51 “Study Units” across the Nation. (Summary reports of findings from the Study Units are available online; see back page). Regional assessments will complement and extend the findings of the Study Units to fill critical gaps in our understanding of ground-water quality and flow over broad regions, and determine trends at sites that have been monitored for more than a decade. The assessments will increase our understanding of how natural features and human activities affect ground-water quality. For example, regional differences in climate, geology, land use, and other factors can lead to regional differences in water quality among aquifer systems. Such regional variations can be analyzed using the large data set from NAWQA’s Cycle I. Water-quality information in a regional context will be useful for regional monitoring councils, States, and localities in addressing priority water-quality and drinking-water issues in their areas. For example, regional-scale analyses, models, and other scientific tools will help with extrapolating findings to unmonitored, comparable areas in other parts of the regions. Data sets from multiple States representing similar hydrogeologic settings can be used by States and localities to assess, protect and manage their water resources more cost effectively. Other activities planned during Cycle II include regional assessments of streams and rivers; continuing national syntheses of information on pesticides, volatile organic compounds (VOCs), nutrients, and selected trace elements; and national topical studies of mercury, the fate of agricultural chemicals, effects of urbanization on stream ecosystems, nutrient enrichment, and the transport of contaminants to drinking-water wells (Gilliom and others, 2001; see back page for on-line sources of information about these activities and information).