{ "culture": "en-US", "name": "Aquifer_Recharge_Near_Surface_IN", "guid": "", "catalogPath": "", "snippet": "This data set was created to support a statistical regression analysis of groundwater recharge rates in shallow unconsolidated aquifers, Indiana.", "description": "Aquifer_Recharge_Near_Surface_IN is a raster data layer that displays the results of a regression analysis to determine the estimated rate of diffuse groundwater recharge to the water table in shallow aquifers in Indiana based on numerous landscape-level variables as predictors. The goal of this project was to use an objective, reproducible methodology to estimate groundwater recharge rates in both glaciated and driftless environments. This groundwater-recharge raster layer was developed by combining a multiple regression analysis of groundwater recharge with characteristics of near-surface geologic materials. The groundwater recharge data used in the multiple regression analysis was derived from calculations of groundwater baseflow and surface-water runoff for 279 streams in Indiana. Estimates of groundwater base flow were determined using hydrograph separation analysis (Institute of Hydrology, 1980) determined using a local-minimums approach with a recession slope test, and were converted to recharge by multiplying by using estimates of runoff following Wolock (2003). The baseflow index (BFI) provides the proportion of runoff that is assumed to be groundwater contribution, so recharge was estimated as BFI * interpolated statewide runoff (not runoff per basin). The average annual rate of groundwater recharge (in/year) was used as the dependent variable in a multiple regression analysis using ordinary least squares with several landscape and morphometric independent variables representing geologic, terrain, climate, and hydrogeologic characteristics. The regression model developed for Indiana had a global R2 value of 0.50, and the most influential variables at the 95% confidence level were:\n\n- Cumulative percent area of upstream impervious surfaces\n- Surface clay thickness\n- Percent of clay in soil\n- Average annual air temperature\n- Presence/absence of unconsolidated aquifers\n- Slope of ground surface\n- Cumulative percent area of upstream water bodies\n- Sand composition of water well boreholes\n- Cumulative percent area of upstream medium-height vegetation\n- Hydrologic group classification of soil (A,B,C,D - SSURGO)\n\nThe regression model was used as a mapping tool to spatially distribute estimates of recharge across Indiana, incorporating details of the important landscape variables.", "summary": "This data set was created to support a statistical regression analysis of groundwater recharge rates in shallow unconsolidated aquifers, Indiana.", "title": "Aquifer Recharge Near Surface IN", "tags": [ "geoscientificinformation", "Indiana Geological Survey (IGS)", "groundwater", "recharge", "aquifer", "regression", "probability", "landscape variables", "aquifer sensitivity", "contamination", "Indiana", "Adams County", "Allen County", "Bartholomew County", "Benton County", "Blackford County", "Boone County", "Brown County", "Carroll County", "Cass County", "Clark County", "Clay County", "Clinton County", "Crawford County", "Daviess County", "Dearborn County", "Decatur County", "Dekalb County", "Delaware County", "Dubois County", "Elkhart County", "Fayette County", "Floyd County", "Fountain County", "Franklin County", "Fulton County", "Gibson County", "Grant County", "Greene County", "Hamilton County", "Hancock County", "Harrison County", "Hendricks County", "Henry County", "Howard County", "Huntington County", "Jackson County", "Jasper County", "Jay County", "Jefferson County", "Jennings County", "Johnson County", "Knox County", "Kosciusko County", "Lagrange County", "Lake County", "LaPorte County", "Lawrence County", "Madison County", "Marion County", "Marshall County", "Martin County", "Miami County", "Monroe County", "Montgomery County", "Morgan County", "Newton County", "Noble County", "Ohio County", "Orange County", "Owen County", "Parke County", "Perry County", "Pike County", "Porter County", "Posey County", "Pulaski County", "Putnam County", "Randolph County", "Ripley County", "Rush County", "Scott County", "Shelby County", "Spencer County", "Starke County", "Steuben County", "St Joseph County", "Sullivan County", "Switzerland County", "Tippecanoe County", "Tipton County", "Union County", "Vanderburgh County", "Vermillion County", "Vigo County", "Wabash County", "Warren County", "Warrick County", "Washington County", "Wayne County", "Wells County", "White County", "Whitley County" ], "type": "Image Service", "typeKeywords": [ "ArcGIS Server", "Data", "Image Service", "Service" ], "thumbnail": "", "url": "https://portal.igs.indiana.edu/arcgis", "minScale": 9225483.461124822, "maxScale": 72074.08954003768, "spatialReference": "NAD_1983_UTM_Zone_16N", "accessInformation": "", "licenseInfo": "DATA DISCLAIMER:\nThis data set was compiled by Indiana University, Indiana Geological\nSurvey, using data believed to be accurate; however, a degree of error is\ninherent in all data. This product is distributed \"AS-IS\" without\nwarranties of any kind, either expressed or implied, including but not\nlimited to warranties of suitability to a particular purpose or use. No\nattempt has been made in either the design or production of these data to\ndefine the limits or jurisdiction of any federal, state, or local\ngovernment. These data are intended for use only at the published scale\nor smaller and are for reference purposes only. They are not to be\nconstrued as a legal document or survey instrument. A detailed on-the-\nground survey and historical analysis of a single site may differ from\nthese data.\n\nCOPYRIGHT 2015, THE TRUSTEES OF INDIANA UNIVERSITY, INDIANA GEOLOGICAL SURVEY, ALL RIGHTS RESERVED\n\nCREDIT\nIt is requested that the Indiana Geological Survey be cited in any products generated from this data. The following source citation should be included: Aquifer_Recharge_Near_Surface_IN: Groundwater recharge rates to shallow aquifers, Indiana (Indiana Geological Survey, 100-Meter TIFF Image), digital compilation by Sally L. Letsinger, 2015.\n\nWARRANTY:\nIndiana University, Indiana Geological Survey warrants that the media on\nwhich this product is stored will be free from defect in materials and\nworkmanship for ninety (90) days from the date of acquisition. If such a\ndefect is found, return the media to Publication Sales, Indiana\nGeological Survey, 611 North Walnut Grove Avenue, Bloomington, Indiana 47405\n2208, and it will be replaced free of charge.\n\nLIMITATION OF WARRANTIES AND LIABILITY:\nExcept for the expressed warranty above, the product is provided \"AS IS\",\nwithout any other warranties or conditions, expressed or implied,\nincluding, but not limited to, warranties for product quality, or\nsuitability to a particular purpose or use. The risk or liability\nresulting from the use of this product is assumed by the user. Indiana\nUniversity, Indiana Geological Survey shares no liability with product\nusers indirect, incidental, special, or consequential damages whatsoever,\nincluding, but not limited to, loss of revenue or profit, lost or damaged\ndata or other commercial or economic loss. Indiana University, Indiana\nGeological Survey is not responsible for claims by a third party. The\nmaximum aggregate liability to the original purchaser shall not exceed\nthe amount paid by you for the product.", "portalUrl": "" }