David L. Blodgett 20220906 tabular digital data https://doi.org/10.5066/P9W79I7Q The comid field of these data can be used to join to the NHDPlus version 2 flowline comid or catchment featureid attributes. The included attributes follow the same data model as the NHDPlusV2 but include numerous updates and improvements to network connectivity. All attributes that depend on network connectivity have been recalculated. These attributes are based on the National Hydrography Dataset Plus V2.1 (NHDPlusV2) network geometry and modifications retrieved from the National Water Model V2.1 (NWMv2.1) and "E2NHDPlusV2_us: Database of Ancillary Hydrologic Attributes and Modified Routing for NHDPlus Version 2.1 Flowlines" (E2NHDPlusV2) datasets. The attributes included are: comid, tocomid, fcode, nameID, lengthkm, reachcode, frommeas, tomeas, arbolate_sum, terminalpa ,hydroseq, levelpathi, pathlength, dnhydroseq, areasqkm, totdasqkm, terminalfl, dnlevelpat. These attributes are available in three formats: csv, fst, and parquet. "fst" is a high performance format for use with the R programming language "fst" package. "parquet" is a high performance format for use with multiple programming languages (including pythong) that support the Apache Arrow Parquet format. These data are part of a broader reference hydrologic geospatial fabric being developed in support of national integrated hydrologic modelling and data integration. As noted below, many of these are derived directly from the NHDPlusV2 database. Others are selectively overridden according to modifications found in the NWMv2.1 and E2NHDPlusV2, and some have been recalculated based on algorithms defined in the NHDPlusV2 user's manual and implemented in the nhdplusTools R package. NHDPlusV2: https://www.epa.gov/waterdata/get-nhdplus-national-hydrography-dataset-plus-data nhdplusTools: https://doi.org/10.5066/P97AS8JD E2NHDPlusV2: https://doi.org/10.5066/p986kzem NWMv2.1: https://www.nohrsc.noaa.gov/pub/staff/keicher/NWM_live/NWM_parameters/ comid: integer derived from NHDPlusV2, tocomid: integer derived from tonode/fromnode topology of NHDPlusV2, E2NHDPlusV2, and tocomid attributes of the NWMv2.1 routelink file, fcode: integer derived from NHDPlusV2, gnis_id: integer GNIS_ID derived from NHDPlusV2, reachcode: character derived from NHDPlusV2, frommeas: numeric derived from NHDPlusV2, tomeas: numeric derived from NHDPlusV2, lengthkm: numeric derived from NHDPlusV2, arbolate_sum: numeric recalculated with nhdplusTools, areasqkm: numeric derived from NHDPlusV2, totdasqkm: numeric recalculated with nhdplusTools, hydroseq: integer recalculated with nhdplusTools, dnhydroseq: integer recalculated with nhdplusTools, levelpathi: integer recalculated with nhdplusTools, dnlevelpat: integer recalculated with nhdplusTools, terminalpa: integer recalculated with nhdplusTools, terminalfl: integer (1 or 0) recalculated with nhdplusTools, pathlength: numeric recalculated with nhdplusTools. streamleve: integer recalculated with nhdplusTools. streamorde: integer recalculated with nhdplusTools. vpuin: logical derived from NHDPlusV2, vpuout: logical derived from NHDPlusV2, wbareatype: character derived from NHDPlusV2, slope: numeric derived from NHDPlusV2, slopelenkm: numeric derived from NHDPlusV2, ftype: character derived from NHDPlusV2, gnis_name: character derived from NHDPlusV2, gnis_id: integer derived from NHDPlusV2, wbareacomi: integer derived from NHDPlusV2, hwnodesqkm: numeric derived from NHDPlusV2, rpuid: character derived from NHDPlusV2, vpuid: character derived from NHDPlusV2, roughness: numeric derived from NHDPlusV2 20220510 publication date Complete None planned -125.5078 -65.3906 49.6107 24.2069 ISO 19115 Topic Category inlandWaters None hydrology hydrography network USGS Metadata Identifier USGS:60c92503d34e86b9389df1c9 None Conterminous US None. Please see 'Distribution Info' for details. None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. David L Blodgett U.S. Geological Survey, WATER Civil Engineer mailing address

One Gifford Pinchot Drive

Madison WI 53726 US 608-628-5855 dblodgett@usgs.gov All values physical (length and area) attributes were derived from NHDPlusV2. Topological connectivity updates derived from E2NHDPlusV2 and NWMv2.1 are documented as part of those data sources. These data have been tested rigorously and used for numerous value-adding data processing workflows. These data are complete in that they include all NHDPlusV2 network flowlines. The NHDPlusV2 does not include complete coverage for watersheds outside of the coterminous US. Lucinda McKay 20150101 vector digital data https://www.epa.gov/waterdata/get-nhdplus-national-hydrography-dataset-plus-data 100000 Digital 20150101 publication date NHDPlusV2 Primary source of network attributes Greg Schwarz 2019 tabular digital data https://www.sciencebase.gov U.S. Geological Survey https://doi.org/10.5066/p986kzem Digital 20191206 publication date E2NHDPlusV2 Source of updated network topology NOAA Office of Water Prediction 20210414 tabular digital data https://www.nohrsc.noaa.gov/pub/staff/keicher/NWM_live/NWM_parameters/ https://www.nohrsc.noaa.gov/pub/staff/keicher/NWM_live/NWM_parameters/NWM_parameter_files_v2.1.tar.gz Digital 20210414 publication date NWMv2.1 Source of updated network topology. Load and normalize data. Attribute names aligned and unneeded content removed. NHDPlusV2 NWMv2.1 E2NHDPlusV2 20220101 Cleaned up network, added tocomid from tonode/fromnode topology, removed unwanted modifications from E2NHDPlusV2 and NWMv2.1. 20220101 Used nhdplusTools to add plus network attributes. Blodgett, D., Johnson, J.M., 2022, nhdplusTools: Tools for Accessing and Working with the NHDPlus, https://doi.org/10.5066/P97AS8JD 20220101 Basic QA/QC to verify data fall in expected ranges and that there are no missing or invalid values are included. 20220101 Createed additional file formats of csv data (fst and parquet). fst for fast access in R and parquet for portable fast data access. 20220101 enhd_nhdplusatts.csv Comma Separated Value (CSV) file containing all attributes generated by workflow. U.S. Geological Survey comid integer derived from NHDPlusV2 NHDPlusV2 847 948090822 tocomid integer derived from tonode/fromnode topology of NHDPlusV2, E2NHDPlusV2, and tocomid attributes of the NWMv2.1 routelink file U.S. Geological Survey 0 948100477 fcode integer derived from NHDPlusV2 NHDPlusV2 46003 STREAM/RIVER Hydrographic Category: intermittent NHDPlusV2 46006 STREAM/RIVER Hydrographic Category: perennial NHDPlusV2 55800 ARTIFICIAL PATH NHDPlusV2 33400 CONNECTOR NHDPlusV2 33600 CANAL/DITCH NHDPlusV2 46000 STREAM/RIVER NHDPlusV2 46007 STREAM/RIVER Hydrographic Category: ephemeral NHDPlusV2 42813 PIPELINE Product: water; Pipeline Type: siphon; Relationship to Surface: unspecified NHDPlusV2 42800 PIPELINE NHDPlusV2 42809 PIPELINE Product: water; Pipeline Type: penstock; Relationship to Surface: at or near NHDPlusV2 42803 PIPELINE Product: water; Pipeline Type: aqueduct; Relationship to Surface: underground NHDPlusV2 42801 PIPELINE Product: water; Pipeline Type: aqueduct; Relationship to Surface: at or near NHDPlusV2 33601 CANAL/DITCH Canal/Ditch Type: aqueduct NHDPlusV2 33603 CANAL/DITCH Canal/Ditch Type: stormwater NHDPlusV2 42807 PIPELINE Product: water; Pipeline Type: general case; Relationship to Surface: underground NHDPlusV2 42816 PIPELINE Product: water; Pipeline Type: aqueduct NHDPlusV2 42820 PIPELINE Product: water; Pipeline Type: Stormwater NHDPlusV2 42805 PIPELINE Product: water; Pipeline Type: general case; Relationship to Surface: at or near NHDPlusV2 42823 PIPELINE Product: water; Pipeline Type: Stormwater; Relationship to Surface: Underground NHDPlusV2 42802 PIPELINE Product: water; Pipeline Type: aqueduct; Relationship to Surface: elevated NHDPlusV2 gnis_id integer GNIS_ID derived from NHDPlusV2 NHDPlusV2 399 2559129 reachcode character derived from NHDPlusV2 REACHCODE NHDPlusV2 Joins to the REACHCODE attribute of nhdpusV2 frommeas numeric derived from NHDPlusV2 NHDPlusV2 0 100 percent tomeas numeric derived from NHDPlusV2 NHDPlusV2 0 100 percent lengthkm numeric derived from NHDPlusV2 NHDPlusV2 0.015 95.714 km arbolate_su numeric recalculated with nhdplusTools U.S. Geological Survey 0.015 2136999 areasqkm numeric derived from NHDPlusV2 NHDPlusV2 0.00 65014 totdasqkm numeric recalculated with nhdplusTools U.S. Geological Survey 0 2881158.8 hydroseq integer recalculated with nhdplusTools U.S. Geological Survey 1 2667754 dnhydroseq integer recalculated with nhdplusTools U.S. Geological Survey 0 2667753 levelpathi integer recalculated with nhdplusTools U.S. Geological Survey 1 2667748 dnlevelpat integer recalculated with nhdplusTools U.S. Geological Survey 0 2667748 terminalpa integer recalculated with nhdplusTools U.S. Geological Survey 1 2667748 terminalfl integer (1 or 0) recalculated with nhdplusTools U.S. Geological Survey 1 terminal flowline Producer defined 0 non-terminal flowline Producer defined pathlength numeric recalculated with nhdplusTools U.S. Geological Survey 0 6039.8 km streamleve integer recalculated with nhdplusTools U.S. Geological Survey 1 13 streamorde integer recalculated with nhdplusTools U.S. Geological Survey 1 10 vpuin integer 0 or 1 indicates if flowline is an inflow to a vpu U.S. Geological Survey 0 1 vpuout integer 0 or 1 indicates if flowline is an outflow from a vpu U.S. Geological Survey 0 1 wbareatype character indicates the type of the waterbody a flowline is related to U.S. Geological Survey StreamRiver Stream or River NHDPlusV2 CanalDitch Canal or Ditch NHDPlusV2 LakePond Lake or Pond NHDPlusV2 Wash Wash NHDPlusV2 Reservoir Reservoir NHDPlusV2 Area of Complex Channels Area of Complex Channels NHDPlusV2 slope numeric average slope of flowline U.S. Geological Survey -9998 4.6 slopelenkm numeric length used for slope calculation U.S. Geological Survey 0.001 95.714 km ftype Feature type of flowline U.S. Geological Survey StreamRiver Stream or River NHDPlusV2 CanalDitch Canal or Ditch NHDPlusV2 Artificial Path Artificial Path NHDPlusV2 Connector Connector NHDPlusV2 Pipeline Pipeline NHDPlusV2 gnis_name character GNIS Name U.S. Geological Survey GNIS Names gnis_id integer GNIS ID U.S. Geological Survey 399 2559129 wbareacomi comid of water body the flowline associates to U.S. Geological Survey -9999 948100002 hwnodesqkm drainage area at the upstream node of a first order flowline U.S. Geological Survey 0 7982.6238 square km rpuid character identifier for raster processing unit flowline belongs to U.S. Geological Survey Raster Processing Unit NHDPlusV2 18c Raster Processing Unit 18c NHDPlusV2 Raster Processing Unit NHDPlusV2 18b Raster Processing Unit 18b NHDPlusV2 18a Raster Processing Unit 18a NHDPlusV2 14a Raster Processing Unit 14a NHDPlusV2 14b Raster Processing Unit 14b NHDPlusV2 15b Raster Processing Unit 15b NHDPlusV2 15a Raster Processing Unit 15a NHDPlusV2 16b Raster Processing Unit 16b NHDPlusV2 16a Raster Processing Unit 16a NHDPlusV2 04b Raster Processing Unit 04b NHDPlusV2 04d Raster Processing Unit 04d NHDPlusV2 04c Raster Processing Unit 04c NHDPlusV2 04a Raster Processing Unit 04a NHDPlusV2 02b Raster Processing Unit 02b NHDPlusV2 02a Raster Processing Unit 02a NHDPlusV2 05d Raster Processing Unit 05d NHDPlusV2 05c Raster Processing Unit 05c NHDPlusV2 05a Raster Processing Unit 05a NHDPlusV2 05b Raster Processing Unit 05b NHDPlusV2 06a Raster Processing Unit 06a NHDPlusV2 07c Raster Processing Unit 07c NHDPlusV2 07b Raster Processing Unit 07b NHDPlusV2 07a Raster Processing Unit 07a NHDPlusV2 03g Raster Processing Unit 03g NHDPlusV2 08b Raster Processing Unit 08b NHDPlusV2 08a Raster Processing Unit 08a NHDPlusV2 10c Raster Processing Unit 10c NHDPlusV2 10d Raster Processing Unit 10d NHDPlusV2 10b Raster Processing Unit 10b NHDPlusV2 10a Raster Processing Unit 10a NHDPlusV2 10i Raster Processing Unit 10i NHDPlusV2 10h Raster Processing Unit 10h NHDPlusV2 10g Raster Processing Unit 10g NHDPlusV2 10f Raster Processing Unit 10f NHDPlusV2 10e Raster Processing Unit 10e NHDPlusV2 11c Raster Processing Unit 11c NHDPlusV2 11d Raster Processing Unit 11d NHDPlusV2 11b Raster Processing Unit 11b NHDPlusV2 11a Raster Processing Unit 11a NHDPlusV2 01a Raster Processing Unit 01a NHDPlusV2 17b Raster Processing Unit 17b NHDPlusV2 17a Raster Processing Unit 17a NHDPlusV2 17c Raster Processing Unit 17c NHDPlusV2 17d Raster Processing Unit 17d NHDPlusV2 13a Raster Processing Unit 13a NHDPlusV2 13b Raster Processing Unit 13b NHDPlusV2 13c Raster Processing Unit 13c NHDPlusV2 13d Raster Processing Unit 13d NHDPlusV2 03a Raster Processing Unit 03a NHDPlusV2 03b Raster Processing Unit 03b NHDPlusV2 03c Raster Processing Unit 03c NHDPlusV2 03d Raster Processing Unit 03d NHDPlusV2 03e Raster Processing Unit 03e NHDPlusV2 03f Raster Processing Unit 03f NHDPlusV2 09a Raster Processing Unit 09a NHDPlusV2 12a Raster Processing Unit 12a NHDPlusV2 12b Raster Processing Unit 12b NHDPlusV2 12c Raster Processing Unit 12c NHDPlusV2 12d Raster Processing Unit 12d NHDPlusV2 vpuid U.S. Geological Survey 18 Vector Processing Unit 18 NHDPlusV2 14 Vector Processing Unit 14 NHDPlusV2 15 Vector Processing Unit 15 NHDPlusV2 16 Vector Processing Unit 16 NHDPlusV2 04 Vector Processing Unit 04 NHDPlusV2 02 Vector Processing Unit 02 NHDPlusV2 05 Vector Processing Unit 05 NHDPlusV2 06 Vector Processing Unit 06 NHDPlusV2 07 Vector Processing Unit 07 NHDPlusV2 08 Vector Processing Unit 08 NHDPlusV2 10L Vector Processing Unit 10L NHDPlusV2 10U Vector Processing Unit 10U NHDPlusV2 11 Vector Processing Unit 11 NHDPlusV2 01 Vector Processing Unit 01 NHDPlusV2 17 Vector Processing Unit 17 NHDPlusV2 13 Vector Processing Unit 13 NHDPlusV2 03N Vector Processing Unit 03N NHDPlusV2 03S Vector Processing Unit 03S NHDPlusV2 03W Vector Processing Unit 03W NHDPlusV2 09 Vector Processing Unit 09 NHDPlusV2 12 Vector Processing Unit 12 NHDPlusV2 roughness numeric Manning's N estimate for flowline U.S. Geological Survey 0.0034 2.0159 Mannings N U.S. Geological Survey GS ScienceBase mailing address

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Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov 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 on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P9W79I7Q None 20220906 David L Blodgett U.S. Geological Survey, WATER Civil Engineer mailing address

One Gifford Pinchot Drive

Madison WI 53726 US 608-628-5855 dblodgett@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998