{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Michael E. Wieczorek", "hasEmail": "mailto:mewieczo@usgs.gov"}, "description": "This data set represents the average contact time, in units of days, compiled for every catchment of \nNHDPlus for the conterminous United States. Contact time, as described in Wolock and others (1989), \nis the baseflow residence time in the subsurface. The source data set was the U.S. Geological Survey's \n(USGS)  1-kilometer grid for the conterminous United States (D.M. Wolock, U.S. Geological Survey, \nwritten commun., 2008). The grid was created using a method described by Wolock and others (1997a; \nsee equation 3). In the source data set, the contact time was estimated from 1-kilometer resolution \nelevation data (Verdin and Greenlee, 1996 ) and STATSGO soil characteristics (Wolock, 1997b).\n\t\t\nThe NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates \nmany of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset \n(NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, \nnaming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments \n(drainage areas) produced using a drainage enforcement technique first widely used in New England, \nand thus referred to as \"the New England Method.\" This technique involves \"burning in\" the 1:100,000-scale \nNHD and when available building \"walls\" using the National Watershed Boundary Dataset (WBD). The \nresulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree \nwith the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey \n(USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method \nproduces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus \ndataset is organized by 18 Production Units that cover the conterminous United States.\n\t\t\nThe NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's  Major River Basins (MRBs, \nCrawford and others, 2006).  MRB1, covering the New England and Mid-Atlantic River basins, contains \nNHDPlus Production Units 1 and 2.  MRB2, covering the South Atlantic-Gulf and Tennessee River basins, \ncontains NHDPlus Production Units 3 and 6.  MRB3, covering the Great Lakes, Ohio, Upper Mississippi, \nand Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9.  MRB4, covering \nthe Missouri River basins, contains NHDPlus Production Units 10-lower and 10-upper.  MRB5, covering \nthe Lower Mississippi, Arkansas-White-Red, and Texas-Gulf River basins, contains NHDPlus Production \nUnits 8, 11 and 12.  MRB6, covering the Rio Grande, Colorado and Great Basin River basins, contains \nNHDPlus Production Units 13, 14, 15 and 16.  MRB7, covering the Pacific Northwest River basins, \ncontains NHDPlus Production Unit 17.  MRB8, covering California River basins, contains NHDPlus \nProduction Unit 18.", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/P9NYJRJC", "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.802df197-dacb-4061-befe-a10991a4cbd7.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_802df197-dacb-4061-befe-a10991a4cbd7", "keyword": ["CALI", "COGB", "California", "Catchment", "Contact time", "Conterminous United States", "GLMR", "Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy", "Inlandwaters", "LMTG", "Lower Mississippi, Arkansas-White-Red, and Texas-Gulf", "MORI", "MRB", "MRB1", "MRB2", "MRB3", "MRB4", "MRB5", "MRB6", "MRB7", "MRB8", "Major River Basin", "Missouri", "NAWQA", "NEMA", "NHDPlus", "New England and Mid-Atlantic", "PANW", "Pacific Northwest", "Rio Grande, Colorado, and Great Basin", "SAGT", "SPARROW", "South Atlantic-Gulf and Tennessee", "USGS:802df197-dacb-4061-befe-a10991a4cbd7", "environment", "geoscientificInformation", "inlandWaters"], "modified": "2020-11-17T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-127.910792, 23.243486, -65.327751, 51.657387", "theme": ["geospatial"], "title": "Attributes for NHDPlus Catchments (Version 1.1)for the Conterminous United States: Contact Time, 2002"}