U.S. Geological Survey 2023 vector and raster digital data https://www.usgs.gov/national-hydrography https://www.usgs.gov/the-national-map-data-delivery U.S. Geological Survey 2023 https://www.sciencebase.gov/catalog/item/57645ff2e4b07657d19ba8e8 The High Resolution National Hydrography Dataset Plus (NHDPlus HR) is an integrated datset of geospatial data layers, including the most current National Hydrography Dataset (NHD), the 10-meter 3D Elevation Program Digital Elevation Model (3DEP DEM), and the National Watershed Boundary Dataset (WBD). The NHDPlus HR combines the NHD, 3DEP DEMs, and WBD to create a stream network with linear referencing, feature naming, "value added attributes" (VAAs), elevation-derived catchments, and other features for hydrologic data analysis. The stream network with linear referencing is a system of data relationships applied to hydrographic systems so that one stream reach "flows" into another and "events" can be tied to and traced along the network. The VAAs provide capabilities for upstream and downstream navigation with linear referencing, analysis, and modeling. The elevation derived catchments are used to associate other landscape attributes, such as land cover, with stream segments. These data are intended for geographic display and analysis at the watershed level. The data should be displayed and analyzed at scales appropriate for 1:24,000-scale data. No responsibility is assumed by the U.S. Geological Survey in the use of these data. This data comprises hydrological data, including flow lines, water bodies and water features. 2019 2023 publication date Complete notPlanned -179.0 -64.0 72.0 10.0 USGS Metadata Identifier USGS:0826ab39-e5bd-47e6-ba8f-56f340094f81 ISO 19115 Topic Category elevation environment geoscientificInformation imageryBaseMapsEarthCover inlandWaters USGS Thesaurus geospatial analysis streamflow hydrographic datasets hydrology water resources river reaches land surface characteristics topography cartography earth sciences geographic information systems digital elevation models surface water quality None Administrative watershed units Area of Complex Channels Area to be submerged artificial path Basin Bay/Inlet boundaries Boundaries Boundary Bridge Canal/Ditch Coastline Connector Dam/Weir dams Drainage area for surface water drainage systems and characteristics Estuary FileGDB Flow direction network Flume ForeShore Gaging Station Gate GeoPackage Hazard Zone HU10 HU12 HU14 HU16 HU2 HU4 HU6 HU8 HUC Hydrographic Hydrography Hydrologic Unit Code Hydrologic Units Hydrologic Unit Ice mass Inundation Area Lake Levee Line Lock Chamber Marsh Nonearthen Shore Playa Point PointEvent Pond Rapids Reach Reach code Reef Region Reservoir River Rock Sea/Ocean Sink/Rise Sounding Datum Line Special Use Zone Special Use Zone Limit Spillway Stream Stream/River Submerged Stream surface water systems surface water Swamp Topographic Tunnel Underground Conduit Wall Wash Water Intake Outflow Waterfall Watershed Watershed Boundaries Watershed Boundary Dataset WBD Well watersheds drainage basins catchment streamflow data NHDPlus High Resolution (NHDPlus HR) Geographic Names Information System US United States None None. All data are open and non-proprietary. However, users should be aware that temporal changes may have occurred since this dataset was collected and that some parts of this data may no longer represent actual conditions. Users should not use this data for critical applications without a full awareness of its limitations. This dataset is not intended to be used for site-specific regulatory determinations. Acknowledgment of the U.S. Geological Survey would be appreciated for products derived from these data. U.S. Geological Survey mailing and physical

12201 Sunrise Valley Drive

Reston VA 20192 1-888-ASK-USGS (1-888-275-8747) tnm_help@usgs.gov Monday through Friday 8:00 AM to 4:00 PM Eastern Time Zone USA Please visit https://answers.usgs.gov/, call 1-888-ASK-USGS or email tnm_help@usgs.gov to contact us. https://ngtoc-metadata.nationalmap.gov/collections/browse/hydro_nhdplus_hr_browse.jpg Thumbnail JPG image JPEG The U.S. Geological Survey (USGS). None Unclassified None Attributes are not systematically verified. Attribute errors may be present. Data is not expected to contain any topological errors. Network connectivity was verified by tracing upstream from outlets. Topology between drainage area lines and polygons, streams, waterbodies, coastlines, and gages was checked for vertical integration in the national data sets. Not all hydrologic features on the ground (e.g. stream/river, lake/pond, etc.) may be mapped, and changes may have occurred since originally mapped. The level of mapping detail varies by geographic area. The USGS jointly manages these data with local and regional data stewards, usually at the State level, and some variations in content occur based on differences in local/regional stewardship. Horizontal accuracy for source data may be available in the original source product metadata file where available. Vertical accuracy for elevation data may be available in the original source product metadata file where available. U.S. Geological Survey 2023 vector and raster digital data https://www.usgs.gov/national-hydrography 24000 Geospatial dataset 2016 2023 publication date NHD The most current NHD available at the time of production was used in conjunction with the most current WBD, and 3DEP DEMs available to create a hydro-enforced DEM for generation of the catchment raster and feature class, and flow direction/accumulation rasters, and used to compute and assign NHDFlowline Value Added Attributes (VAAs). U.S. Geological Survey Unknown vector and raster digital data https://www.usgs.gov/core-science-systems/ngp/3dep Geospatial dataset 1985 2022 publication date 3DEP DEM The most current 3DEP DEM available at time of production was used in combination with the most current NHD and WBD availble at the time of production to create a hydro-enforced DEM, NHDPlus HR Catchments, and surface flow direction and accumulation rasters. Stream elevations from 3DEP DEMs were used to help derive stream slope and stream velocity. U.S. Geological Survey 2022 vector and raster digital data 24000 Geospatial dataset 2016 2022 publication date WBD The most current 12-digit Hydrologic Unit (HU12) boundaries from the Watershed Boundary Dataset (WBD) available at the time of production were used as ridgeline enforcement input in a process called "walling" in the production of hydro-enforced DEMs. Closed basin designations, from the HU12 polygon data were used to impose "sinks" in the hydro-enforced DEMs. NHDPlus HR Build/Refresh Process Initial production set-up:,Create NHDPlus HR Workspace, Create CatMask and Raster Catalog, Prep Elevation Data A. NHD Prep. 1. Run NHDPlus NHDQAQC. 2. Set up GlobalData fgdb, populate VPUSeqNo B. Create NHDPlus HR (VPUID) fgdb, populate with NHD/WBD data. Assign NHDPlusIDs, VPUIDs. Update NHD data, if necessary, update NHDPlusConnect.C. Populate NHDFlowline-based attribute tbls/FCs and compute VAAs (part 1). D. Edit DivFracMP E. QAQC DivFracMP F. Compute VAAs (part 2) G. Trim BurnLineEvent H. Create Raster Workspace, create elev_cm.tif shdrelief.jp2 and elev_source.gdb. I. Create and edit burn components, as needed J. Create Sinks. Examine and Fix sinks, as needed. K. Deprecated L.Create FDR, Catchments and other rasters. M. Review Step L results. N. Deprecated O. Calculate HW Node Areas and Raw Elevations. P. Create Flow Accumulation Raster. Q. Smooth Raw Elevations. R. Accumulate Catchment areas propagate VAAs to upstream VPUs. S Allocate Runoff, Temp, Precip and other EROM Inputs. T. Populate EROM Mean Annual Stream Flow Estimates, QAQC and Velocity. U. Populate NHDPlusProcessingParameter Table. NHDPlusHR National aggregates all NHDPlus HR VPU datasets into one seamless file geodatabase. Process date below is when the NHDPlus HR data was aggregated 20211210 1.0E-5 1.0E-5 Decimal degrees North American Datum of 1983 Geodetic Reference System 80 6378137.0 298.2572221 North American Vertical Datum of 1988 0.001 meters Implicit coordinate U.S. Geological Survey - National Geospatial Program Office mailing and physical

12201 Sunrise Valley Drive

Reston VA 20192 USA 1-888-275-8747 tnm_help@usgs.gov Monday through Friday 8:00 AM to 4:00 PM Eastern Time Zone USA Please visit https://answers.usgs.gov/, call 1-888-ASK-USGS or email tnm_help@usgs.gov to contact us. Downloadable Data Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Cloud Cloud Storage https://prd-tnm.s3.amazonaws.com/index.html?prefix=StagedProducts/Hydrography/NHDPlusHR/ None 20230913 U.S. Geological Survey - National Geospatial Program Office mailing and physical

12201 Sunrise Valley Drive

Reston VA 20192 USA 1-888-275-8747 tnm_help@usgs.gov Monday through Friday 8:00 AM to 4:00 PM Eastern Time Zone USA Please visit https://answers.usgs.gov/, call 1-888-ASK-USGS or email tnm_help@usgs.gov to contact us. Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 local time None None None Unclassified None