{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Jeremy Decker", "hasEmail": "mailto:jdecker@usgs.gov"}, "description": "The U.S. Geological Survey (USGS), in cooperation with the U.S Fish and Wildlife Service, \nhas investigated the hydrology of the Great Dismal Swamp (Swamp) National Wildlife Refuge \n(Refuge) in Virginia and North Carolina and developed a three-dimensional numerical model to \nsimulate groundwater and surface-water hydrology. The model was developed with \nMODFLOW-NWT, a USGS numerical groundwater flow modeling program, in combination \nwith the Surface-Water Routing Process, a software package that simulates dynamic \nsurface-water flows, water-control-structure management, and groundwater/surface-water \ninteractions.  The steady-state model was calibrated to average spring conditions using \nautomated parameter estimation software (PEST) to reduce simulation errors and assess \nmodel parameter sensitivity.  The model was then used to simulate wet and dry climatic \nconditions and a variety of hypothetical scenarios in which water levels in the Swamp were \nraised and lowered by simulated management of water control structures.  Results of the \nmodel simulations indicate that, under average spring conditions, precipitation is the primary \nwater input (92%); surface-water (5%) and groundwater (3%) inflows make up the remainder. \nThe primary outflow (or loss) is evapotranspiration (55%), with surface outflows (about 41%) \nand groundwater outflow (about 4%) making up the remainder.  Simulated adjustment of \nwater-control structure weir levels demonstrates that groundwater levels are affected by water \nlevels in adjacent ditches and that surface-water and groundwater levels can be controlled \nthrough management of water control structures, allowing the Refuge to better manage fire \nrisks and preserve forested-wetland ecosystems in the Refuge.  The 13 water control \nstructures proposed in the simulated scenario representing possible future conditions \neffectively raised simulated water levels in the northeastern corner of the study area, a goal \nof the Refuge management.  Results of this study demonstrate use of MODFLOW with the \nSurface-Water Routing Process for simulating water management options in peat wetlands \nand will help Refuge managers to better understand existing hydrologic conditions, assess \nthe hydrologic effects of planned changes to water control structures, and apply the new \nsimulation tool to guide water management on the Refuge.", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/P9445ZGC", "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.5ccdf90a-4bce-402c-a82f-e5c0ba0115b8.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_5ccdf90a-4bce-402c-a82f-e5c0ba0115b8", "keyword": ["Great Dismal Swamp", "Groundwater", "Groundwater Model", "InlandWaters", "MODFLOW", "North Carolina", "PEST", "Surface-water", "USGS:5ccdf90a-4bce-402c-a82f-e5c0ba0115b8", "Virginia", "environment", "geoscientificInformation", "inlandWaters", "usgsgroundwatermodel"], "modified": "2020-11-17T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-76.5788611, 36.4132932, -76.3244162, 36.7693925", "theme": ["geospatial"], "title": "MODFLOW-NWT datasets for simulations of groundwater and surface-water in the Great Dismal Swamp of Virginia and North Carolina"}