This dataset represents data derived from the NLCD dataset and the National Hydrography Dataset version 2.1(NHDPlusV2) (see Data Sources for links to NHDPlusV2 data and NLCD). Attributes were calculated for every local NHDPlusV2 catchment and accumulated upstream catchments riparian area to provide watershed-level metrics for imperviousness values within the NLCD. This data set is derived from the NLCD Impervious Surfaces raster(imp2001) which describes percent imperviousness (continuous data type). Values indicate the degree to which the area is composed of impervious anthropogenic materials (e.g., parking surfaces, roads, building roofs). This raster was produced based on a decision-tree classification of circa 2001 Landsat satellite data.(see Data Structure and Attribute Information for a description of each metric).
OwnerUnited State Environmental Protection Agency - view all
Update frequencyunknown
Last updatedabout 1 year ago
Format
Overviewalabamaarizonaarkansascaliforniacanadacoloradoconnecticutdelawareecosystemenvironmentfloridageorgiaidahoillinoisindianainlandwatersiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimodelingmonitoringmontananatural resourcesnebraskanevadanew hampshirenew jerseynew mexiconew yorknorth carolinanorth dakotaohiooklahomaoregonpennsylvaniarhode islandsouth carolinasouth dakotasurface watertennesseetexasunited statesunited states of americausautahvermontvirginiawashingtonwest virginiawisconsinwyoming
Additional Information
KeyValue
dcat_issued2015-01-21
dcat_modified2015-01-21
dcat_publisher_nameU.S. EPA Office of Research and Development (ORD) - National Health and Environmental Effects Research Laboratory (NHEERL)
guid{A2FD5534-7D59-4E60-BD61-8C2FD95F9D37}
ib1_trust_framework[]
languageen-US