Groundwater-Quality Sampling for the USGS National Water-Quality Assessment Program in Nebraska During 2015

During spring and summer 2015, the U.S. Geological Survey (USGS) Nebraska Water Science Center conducted extensive groundwater quality sampling as a part of the USGS National Water Quality Assessment (NAWQA) program. The main goal of NAWQA is to provide high quality, long-term datasets to aid in understanding natural and anthropogenic factors that affect water quality. Data from three separate NAWQA studies—Principal Aquifer, Vertical Flow Path, and Agriculture and Land Use—is being used to characterize the water quality of three different aquifers in Nebraska. All samples collected for these three studies were analyzed for organic, inorganic, and age-dating constituents. For the Principal Aquifer study, 32 public-supply wells, screened in the deeper portions of the High Plains aquifer, were sampled to evaluate the quality of public drinking water supply. For the Vertical Flow Path study, 15 moderate-depth domestic wells and 15 shallow-depth monitoring wells, screened in shallow quaternary aquifers within the High Plains aquifer in eastern Nebraska, were sampled to evaluate age-related trends of constituents across different land uses. For the Agriculture and Land Use study, 30 monitoring wells in the shallow glacial aquifers of eastern Nebraska were sampled to evaluate the amount of agricultural chemicals. All samples were collected and analyzed using the rigorous and comprehensive NAWQA protocols and methods ensuring high quality, consistent, and reliable data.