MODFLOW-NWT model used to evaluate potential effects of alterations to the hydrologic system in the vicinity of Long Lake, Indiana Dunes National Lakeshore, near Gary, Indiana

A three dimensional groundwater flow model (MODFLOW-NWT) was developed to examine the effects of changes to engineering controls and Lake Michigan surface water levels on the distribution of ponded water near Long Lake in Indiana Dunes National Lakeshore, near Gary, Indiana. The steady state model was calibrated to relatively low groundwater level condition of October 2002 and a relatively high groundwater level condition of March 2011. Scenario models were generated that examined the effects of (1) removing the beaver dams in US-12 ditch, (2) discontinuing seepage of water from the filtration pond east of East Long Lake, (3) discontinuing discharge from US-12 ditch to the Gary Sanitary District sewer system, (4) decreasing discharge [...]