Watershed Approach for the Protection of Drinking Water Supplies in Central Illinois

A number of communities in Central Illinois that depend on surface water supplies for their drinking water have been experiencing water quality problems in recent years. Since the dominant land use in the region is agriculture, most of the water quality problems are generally attributed to changes in agricultural practices, especially application of fertilizers and pesticides. The most pressing drinking water quality problem in Central Illinois is high nitrate concentration. The maximum contaminant level (MCL) for nitrate in drinking water is set at10 milligrams per liter. A Technical Advisory Committee developed a set of recommendations on how to implement watershed-based solutions to the water quality problem in Central Illinois based on the results of several hydrologic and water quality studies.