Significant quantities of mercury have been found in many Indiana streams and in our air. The Indiana Department of Environmental Management maintains a list of which Indiana water bodies are not expected to meet applicable federal water quality standards.
Mercury is one of the pollutants of concern that water quality testing screens for. Indiana water bodies with mercury levels above the federal standards are identified on this list.
The Indiana State Department of Health issues a fish consumption advisory for fish in many Indiana streams because of mercury contamination. This listing places specific fish species, located in specific water bodies, into five different categories based on the amount of contaminant they contain. More information including healthy fish consumption guidelines and information about how consumption advisories are developed is available from the State Department of Health.
Most mercury that is released into the air from coal-fired power plants, incinerators and industrial boilers comes back to earth's surface with rainfall. According to the Indiana Department of Environmental Management (IDEM), mercury has been detected at precipitation monitoring stations throughout North America. IDEM and the U.S. Geological Survey operate a precipitation monitoring network in Indiana. IDEM publishes the currently available data summaries for the Indiana Monitoring Network.