{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Alexander D. Riddle", "hasEmail": "mailto:ariddle@usgs.gov"}, "description": "A previously developed three-dimensional groundwater-flow model that used the MODFLOW-NWT code \nwas updated to simulate the effects of various proposed drainage modifications aimed at reducing \ndischarge to a sanitary sewer system near Long Lake in Indiana Dunes National Lakeshore, near Gary, \nIndiana. The original steady-state model documented in the USGS report (https://pubs.usgs.gov/sir/2013/5003/) \nand data release (https://doi.org/10.5066/F7D21VS2) was calibrated to a low groundwater level/dry weather \ncondition of October 2002 and a high groundwater level/wet weather condition of March 2011. For this study \nthe 2002 and 2011 simulations were updated with elevation data collected from a 2017 survey of primary \nsurface-water features that affect groundwater levels to create dry- or wet-weather \u201cbase\u201d simulations \n(figs. 1 and 2). Eight scenario models were created by modifying the updated 2002 and 2011 base \nsimulations. The scenarios examined the effects of potential modifications to the hydrologic system: \n(scenario 1a) diverting water from US-12 weir (site CS-1) to County Line Road ditch through underground \npipes [figs. 3-6], (scenario 1b) diverting water from US-12 ditch to Spencer ditch, then trenching Spencer \nditch to the County Line Road ditch to drain to the Little Calumet River [figs. 7 and 8], (scenario 2) \nExtending and altering US-12 ditch to flow east toward County Line Road ditch and drain to the Little \nCalumet River [figs. 9 and 10], and (scenario 3) installing culverts under US-12 and adjacent railroad \nlines to connect US-12 ditch with West Long Lake [figs. 11-14]. This data release contains all files and \nassociated information needed to run these additional simulations.\n\t\t\nChanges in water-table position for each scenario simulation are categorized in figures in this data release as \n(1) within 7 feet of the land surface, (2) within 3 feet of the land surface, or (3) above land surface and are \nexpressed relative to the water-table position simulated in the updated dry- or wet-weather base simulations. \nThe descriptions focus primarily on changes to the distribution of groundwater towards the center of the \nmodel domain. Groundwater distributions towards the western edge (west of Grand Blvd.), southwest \n(south of US-20), and eastern edge (towards Ogden Dunes) of model domain show relatively small variations \nin the scenario simulations and are outside of the primary area of interest.\n\t\t\nThe scenario of rerouting water from entry into the Gary sanitary sewer system at the weir at site CS-1 to \nCounty Line Road ditch through underground pipes (scenario 1a; figs. 3-6) used the MODFLOW Drain \nReturn Package to transmit water from the US-12 ditch to a drain return cell at the intersection of County \nLine Road ditch and 5th Avenue. This simulated hydrologic modification produced an expanded area of \nshallow groundwater within 7 feet of the land surface in the areas surrounding the drain return cell location. \nA small groundwater mound developed in the dry-weather underground pipes simulation at the intersection \nof County Line Road and 5th Avenue, with the water table within 3 feet of the land surface. In the dry-weather \nunderground pipes simulation (figs. 3 and 4), the portions of the area between Union Street and County Line \nRoad ditch were inundated. Water-table position changes north of US-12 or west of Spencer Street were \nminimal. In the wet-weather underground pipes simulation (figs. 5 and 6), water ponded at the intersection of \nCounty Line Road and East 5th Avenue. Both dry- and wet-weather underground pipes simulations exhibited \nsimilar patterns of water-table changes, but differences between water-table positions in the underground pipes \nand updated wet-weather base simulations were minimal in areas away from the drain return cell.\n\t\t\nThe scenario of diverting water from US-12 ditch to Spencer ditch then trenching to the County Line Road ditch \n(scenario 1b; figs. 7 and 8) required creation of new drain cells to connect the southern terminus of Spencer \nditch to County Line Road ditch at 5th Avenue. These new drain cells were assigned bottom elevations derived\nfrom the 2017 ditch elevation survey. The simulated diversion and trench decreased the water table throughout \nthe model domain, particularly in the area south of East 4th Avenue, where expansive areas of shallow \ngroundwater were nearly eliminated. Between Spencer ditch and Union Street, the area of groundwater within \n7 feet of the land surface was reduced in both dry- and wet-weather diversion and trench simulations. In most \nof the area just south of US-12 ditch between the US-12 weir (CS-1) and Union Street, the water table was \nsuppressed to more than 3 feet below the land surface in both scenario simulations. In the wet-weather diversion \nand trench simulation, flooded areas south of US-12 and west of County Line Road ditch were minimized and \nchanges to the water-table position north of US-12 or east of County Line Road ditch were minimal.\n\t\t\nThe scenario of extending and altering US-12 ditch to flow east towards County Line Road ditch and drain to the \nLittle Calumet River (scenario 2; figs. 9 and 10) required creation of drain cells to connect the two ditches. New \ndrain cells were assigned bottom elevations derived from the 2017 ditch elevation survey which intersected the \nsimulated water table of the updated dry- and wet-weather base simulations. The result from the extended \nUS-12 ditch simulation was a suppression of the water table throughout the model domain, with a pronounced \nreduction of shallow groundwater between Union Street and County Line Road ditch. In the dry-weather scenario \nsimulation, the occurrence of ponded water was virtually eliminated in the area of interest, while areas simulated \nto have a water table within 3 feet of the land surface were highly reduced, generally only occurring near West \nLong Lake, East Long Lake, and along some parts of US-12 ditch. Between Spencer Street and Union Street, \nthere were only limited areas with a water table within 7 feet of the land surface. In the wet-weather scenario \nsimulation, groundwater altitudes were sufficiently suppressed as to eliminate nearly all of the inundated areas \nwest of County Line Road and east of Spencer Street (including most of the areas surrounding West Long Lake).\n\t\t\nThe scenario simulating the installation of a culvert under US-12 to connect US-12 ditch to West Long Lake \n(scenario 3; figs. 11-14) utilized MODFLOW\u2019s Drain Return Package to transmit water removed by the US-12 \nditch to a drain return cell in the lake just north of the US-12 and Spencer Street intersection. The general effect \nof this scenario was a substantial increase in water-table altitude throughout the model domain, particularly north \nof US-12. In the dry-weather culvert scenario simulation, the West Long Lake basin defined as the vacant area \nenclosed by US-12 to the south, County Line Road to the east, and Gary neighborhoods to the north was nearly \ncompletely inundated. Several areas of ponded water also developed between Union Street and County Line Road \nDitch. In both the dry- and wet-weather culvert scenario simulations, shallow groundwater extended north from the \nWest Long Lake basin into nearby Gary residential areas. Some isolated areas of ponded water were simulated in \nthe area north from the lake to Lake Michigan in the wet-weather culvert scenario simulation. East of County Line \nRoad ditch, water-table altitudes increased slightly in both dry- and wet-weather culvert scenario simulations but \nthe extent of shallow groundwater did not change or substantially expand when compared with the updated \nwet-weather base simulation. Limited water-table position changes were depicted west of Union Street and south \nof US-12 ditch in both dry- and wet-weather culvert scenario simulations.", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/F7ZP45D5", "description": "Landing page for access to the data", "format": "XML", "mediaType": "application/http", "title": "Digital Data"}, {"@type": "dcat:Distribution", "description": "The metadata original format", "downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.f15061cf-4404-484c-8897-4fa1498dc4f2.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_f15061cf-4404-484c-8897-4fa1498dc4f2", "keyword": ["Calumet aquifer", "Great Lakes", "Groundwater", "Groundwater Flow Modeling", "Indiana", "Indiana Dunes", "Lake Michigan", "MODFLOW-NWT", "NPS", "National Park Service", "USGS:f15061cf-4404-484c-8897-4fa1498dc4f2", "environment", "geoscientificInformation", "groundwater model", "inlandWaters", "usgsgroundwatermodel"], "modified": "2020-11-17T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-87.30, 41.57, -87.16, 41.65", "theme": ["geospatial"], "title": "MODFLOW-NWT model scenarios used to evaluate potential effects of proposed drainage modifications on groundwater discharge in the vicinity of Long Lake, Indiana Dunes National Lakeshore, near Gary, Indiana"}