This report describes the environmental characteristics and water quality at 14 benchmark basins in the Midwestern United States. The information in this report was compiled to aid in the application and interpretation of historical water-quality data collected by the U.S. Geological Survey Hydrologic Benchmark Network program. The streams discussed in this report drain either forested areas or grasslands with a variety of land-use activities that range from recreational use, timber harvesting, and military training on publicly owned land to agriculture and residential development on privately owned land.