The Great and Little Miami River Basins form a National Water Quality Assessment (NAWQA) Program study unit for studying the status, trends, and changes affecting the nation's water quality. Site links to data, publications, maps, and results.
Measured concentrations of many compounds in water people use. Some compounds are regulated as health hazards; a few of these were over the benchmark limits. Others may become issues of concern, so studies such as this give us helpful background levels.