Groundwater provides nearly 50 percent of the Nation’s drinking water. To abet protect this vital resource,the U.
S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Project assesses groundwater quality in aquifers that are important sources of drinking water (Burow and Belitz, 2014). The Rio Grande aquifer system constitutes one of the important areas being evaluated.
Source: usgs.gov