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 from us 12 ditch to the gary sanitary district sewer system 5 connecting east long lake and west long lake 6 deepening county line road ditch and 7 raising and lowering the water level of lake michigan this usgs data release contains all of the input and output files for the simulations described in the associated model documentation report https pubs usgs gov sir 2013 5003