Groundwater Impacts on Coastal Ecosystems

Groundwater seepage (GWS) from coastal aquifers to the ocean, lakes, and rivers has been recognized as an overlooked major source of nutrients (nitrogen, phosphorus, and sulfur) and toxic contaminants (copper and mercury) to aquatic environments. Nutrient and contaminant concentrations in groundwater are often much higher than those in river water. As a consequence, nutrient fluxes from groundwater discharge can exceed fluxes from local rivers. The role of GWS and its impacts is an emerging science. To discuss these issues, a special scientific session was organized and conducted by the Illinois State Geological Survey (ISGS) and the National Oceanic and Atmospheric Administration (NOAA) Center for Sponsored Coastal Ocean Research and Department of Oceanography of Florida State University. The session was held during the AGU/ASLO 2010 Ocean Sciences Meeting, February 22 to 26, 2010, in Portland, Oregon. The goal of the session was to examine the interaction between GWS, watersheds, and coastal waters in order to understand, forecast, and manage impacts to regional coastal ecosystems. More than 30 scientists from the United States, Israel, Brazil, and Australia presented and discussed their scientific findings during the session. Results of this session will help ISGS scientists to develop the NOAA-National Science Foundation collaborative research project entitled "Groundwater/Surface Water Exchange in Lake Michigan: Implications for Nutrient/Trace Element Cycling, Associated Ecological Significance and Climate Change." More information can be found on the Ocean Sciences Meeting web site.

Illustration of groundwater seepages into lakes