{831D980C-FA14-4093-9BE9-CDE589C35339} eng utf8 dataset dataset EnviroAtlas Coordinator U.S. Environmental Protection Agency, Office of Research and Development - Center for Public Health and Environmental Assessment (CPHEA), EnviroAtlas Geospatial Data Owner (919) 541-3832 109 T.W. Alexander Drive Research Triangle Park NC 27709 EnviroAtlas@epa.gov https://www.epa.gov/enviroatlas pointOfContact 2025-07-23 ISO 19139 Geographic Information - Metadata - Implementation Specification 2007 102039 Esri 8.1.2 EnviroAtlas - 2019 Percent Impervious Cover by 12-digit HUC for the Conterminous United States 2021-11-18 creation 2022-03-25 publication U.S. Environmental Protection Agency (US EPA) originator U.S. EPA Office of Research and Development (ORD) - Center for Public Health and Environmental Assessment (CPHEA) Research Triangle Park, NC publisher tableDigital This EnviroAtlas dataset represents the percentage of land area within each 12-digit hydrologic unit code (HUC) in the conterminous United State that is impervious to water infiltration using the National Land Cover Database 2019 (NLCD2019) Percent Developed Impervious dataset. This dataset was produced the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets). This dataset is useful for evaluating the potential value of ecosystem services provided by vegetation communities, and the impacts of developed land cover. The overall goal of EnviroAtlas is to employ and develop the best available science to map indicators of ecosystem services production, demand, and drivers for the nation. completed EnviroAtlas Coordinator U.S. Environmental Protection Agency, Office of Research and Development - Center for Public Health and Environmental Assessment (CPHEA), EnviroAtlas Geospatial Data Owner (919) 541-3832 109 T.W. Alexander Drive Research Triangle Park NC 27709 EnviroAtlas@epa.gov https://www.epa.gov/enviroatlas publisher asNeeded Alabama Arizona Arkansas California Colorado Connecticut Delaware Florida Georgia Idaho Illinois Indiana Iowa Kansas Kentucky Louisiana Maine Maryland Massachusetts Michigan Minnesota Mississippi Missouri Montana Nebraska Nevada New Hampshire New Jersey New Mexico New York North Carolina North Dakota Ohio Oklahoma Oregon Pennsylvania Rhode Island South Carolina South Dakota Tennessee Texas United States Utah Vermont Virginia Washington Washington DC West Virginia Wisconsin Wyoming place EPA Place Names 2015-01-31 publication Ecosystem Environment Human Risk Surface Water Water theme EPA GIS Keyword Thesaurus 2007-11-02 publication 020:072 theme Federal Program Inventory 2013-09-16 publication 12-digit HUCs Ecosystem Services EnviroAtlas Environment Environmental Atlas Land Cover theme User 2022-01-11 publication None. Please check sources, scale, accuracy, currency and other available information. Please confirm that you are using the most recent copy of both data and metadata. Acknowledgement of the EPA would be appreciated. EPA Public Domain License licenseUnrestricted https://edg.epa.gov/EPA_Data_License.html unclassified https://project-open-data.github.io/schema/#accessLevel textTable eng utf8 Microsoft Windows 10 Version 10.0 (Build 18363) ; Esri ArcGIS 12.7.0.26828 true -128.007244 -65.25485 22.868654 51.64959 2019-01-01T00:00:00 2019-12-31T00:00:00 This dataset can be joined to the EnviroAtlas feature class NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS using the field 'HUC_12.' File Geodatabase Table https://enviroatlas.epa.gov/download/CONUS_metrics_FGDB.zip download download https://enviroatlas.epa.gov/download/CONUS_metrics_CSV.zip download download https://www.epa.gov/enviroatlas/enviroatlas-data information information https://www.epa.gov/enviroatlas information information https://enviroatlas-epa.hub.arcgis.com/search?tags=EA-Impervious information information dataset Tests for integrity have not been performed. EPA National Geospatial Data Policy Features have been reviewed by U.S. EPA EnviroAtlas Project Managers for public release. true Features represented have not been tested for completeness EPA National Geospatial Data Policy Features have been reviewed by U.S. EPA EnviroAtlas Project Managers for public release. true Obtained the 12-digit HUC boundary feature class, NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS, from the EnviroAtlas 2015-08-20T00:00:00 This data set is a complete digital hydrologic unit boundary layer to the Subwatershed (12-digit) 6th level for the entire United States. This data set consists of geo-referenced digital data and associated attributes created in accordance with the "Federal Guidelines, Requirements, and Procedures for the National Watershed Boundary Dataset; Chapter 3 of Section A, Federal Standards, Book 11, Collection and Delineation of Spatial Data; Techniques and Methods 11-A3" (04/01/2009). http://www.ncgc.nrcs.usda.gov/products/datasets/watershed/index.html . Polygons are attributed with hydrologic unit codes for 4th level sub-basins, 5th level watersheds, 6th level subwatersheds, name, size, downstream hydrologic unit, type of watershed, non-contributing areas and flow modification. 102039 Esri 8.1.2 EnviroAtlas - HU12_polygon 2015-04-01 publication true -160.247041 -64.565191 17.673736 50.634717 Downloaded the NLCD 2019 Land Cover (CONUS) 2021-11-16T00:00:00 The U.S. Geological Survey (USGS), in partnership with several federal agencies, has developed and released five National Land Cover Database (NLCD) products over the past two decades: NLCD 1992, 2001, 2006, 2011, and 2016. The 2016 release saw landcover created for additional years of 2003, 2008, and 2013. These products provide spatially explicit and reliable information on the Nation's land cover and land cover change. To continue the legacy of NLCD and further establish a long-term monitoring capability for the Nation's land resources, the USGS has designed a new generation of NLCD products named NLCD 2019. The NLCD 2019 design aims to provide innovative, consistent, and robust methodologies for production of a multi-temporal land cover and land cover change database from 2001 to 2019 at 2-3-year intervals. Comprehensive research was conducted and resulted in developed strategies for NLCD 2019: continued integration between impervious surface and all landcover products with impervious surface being directly mapped as developed classes in the landcover, a streamlined compositing process for assembling and preprocessing based on Landsat imagery and geospatial ancillary datasets; a multi-source integrated training data development and decision-tree based land cover classifications; a temporally, spectrally, and spatially integrated land cover change analysis strategy; a hierarchical theme-based post-classification and integration protocol for generating land cover and change products; a continuous fields biophysical parameters modeling method; and an automated scripted operational system for the NLCD 2019 production. The performance of the developed strategies and methods were tested in twenty composite referenced areas throughout the conterminous U.S. An overall accuracy assessment from the 2016 publication give a 91% overall landcover accuracy, with the developed classes also showing a 91% accuracy in overall developed. Results from this study confirm the robustness of this comprehensive and highly automated procedure for NLCD 2019 operational mapping. Questions about the NLCD 2019 land cover product can be directed to the NLCD 2019 land cover mapping team at USGS EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov. See included spatial metadata for more details. National Land Cover Database (NLCD) 2019 Land Cover Conterminous United States 2021-06-04 publication true -130.232828 -63.672192 21.742308 52.877264 2019-01-01T00:00:00 2019-12-31T00:00:00 Downloaded the NLCD 2019 Percent Developed Imperviousness (CONUS) 2021-11-17T00:00:00 NLCD imperviousness products represent urban impervious surfaces as a percentage of developed surface over every 30-meter pixel in the United States. NLCD 2019 updates all previously released versions of impervious products for CONUS and provides integrated analysis for all Land Cover dates. It also includes a matching impervious surface descriptor layer. This descriptor layer identifies types of roads, wind tower sites, building locations, and energy production sites to allow a deeper analysis of developed features. No new imperviousness products for Alaska, Hawaii and Puerto Rico are available from NLCD 2019. Questions about the NLCD 2019 land cover product can be directed to the NLCD 2019 land cover mapping team at USGS EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov. For additional information regarding creation of NLCD percent developed imperviousness products: Dewitz, J., and U.S. Geological Survey, 2021, National Land Cover Database (NLCD) 2019 Products (ver. 2.0, June 2021): U.S. Geological Survey data release, https://doi.org/10.5066/P9KZCM54 Xian, G., Homer, C., Dewitz, J., Fry, J., Hossain, N., and Wickham, J., 2011. The change of impervious surface area between 2001 and 2006 in the conterminous United States. Photogrammetric Engineering and Remote Sensing, Vol. 77(8): 758-762. Yang, L., Huang, C., Homer, C., Wylie, B., and M. Coan. 2003. An approach for mapping large-area impervious surfaces: Synergistic use of Landsat 7 ETM+ and high spatial resolution imagery. Canadian Journal of Remote Sensing, Vol. 29, No. 2, pp.230-240. National Land Cover Database (NLCD) 2019 Impervious Surface Conterminous United States 2021-06-04 publication true -130.232828 -63.672192 21.742308 52.877264 2019-01-01T00:00:00 2019-12-31T00:00:00 Performed a Set Null operation on nlcd_2019_land_cover_l48_20210604.img to eliminate the edge areas (Value = 0) and areas of open water (Value - 11) from the NLCD 2019 Percent Developed Imperviousness (CONUS) raster (nlcd_2019_impervious_l48_20210604.img). Output raster: Imprv2019_NoWater. This allows the use of Zonal Statistics as Table to find the mean imperviousness of the land area within a HUC. 2021-11-18T08:39:00 Used Zonal Statistics as Table and selected 'Mean' as the statistics type. Output table was named pImprv2019 2021-11-18T11:29:00 Added a field to pImprv2019's attribute table named, Pimprv, with the same properties as the MEAN field, and performed a field calculation where Pimprv = MEAN. This operation allows the field, Pimprv, to remain when the pImprv2019 geodatabase table is exported. 2021-11-18T12:07:00 Deleted all fields from pImprv2019's attribute table save Huc_12 and Pimprv 2021-11-18T12:08:00 Joined the pImprv2019 results table to the HUC_12_IDS table. The HUC_12_IDS table has of all of the HUC12 ID values (82,915) used in the EnviroAtlas analyses. This accounts for HUCs that did not have a metric value calculated for them because the input data was missing or the item of interest did not occur in those particular HUCs. For example, some HUCs are comprised completely of water values. Since areas of water were removed from the nlcd_2019_land_cover_l48_20210604 raster, these HUCs will be missing from the output zonal statistics table. 2021-11-18T12:09:00 Exported this joined table using the Table to Table tool in ArcMap. Kept only the HUC12 field and the PIMPRV field. Output table was named, pImprv2019_CONUS. 2021-11-18T12:16:00 asNeeded 2025-07-30