Maintaining accurate data is a concern of all GIS users. The geodatabase offers you the ability to create geographic features that represent the real world. As the real world changes, you must update these features and their attributes. When creating or updating data, you can add behavior to your features and other objects to minimize the potential for errors.After completing this course, you will be able to:Define the two types of attribute domains and discuss how they differ.Create attribute domains and use them when editing data.Create subtypes and use them when editing data.Explain the difference between an attribute domain and a subtype.

The Geodatabase to Shapefile Warning Tool examines feature classes in input file geodatabases for characteristics and data that would be lost or altered if it were transformed into a shapefile. Checks include:
1) large files (feature classes with more than 255 fields or over 2GB), 2) field names longer than 10 characters
string fields longer than 254 characters, 3) date fields with time values 4) NULL values, 5) BLOB, guid, global id, and raster field types, 6) attribute domains or subtypes, and 7) annotation or topology

The results of this inspection are written to a text file ("warning_report_[geodatabase_name]") in the directory where the geodatabase is located. A section at the top provides a list of feature classes and information about the geodatabase as a whole. The report has a section for each valid feature class that returned a warning, with a summary of possible warnings and then more details about issues found.

The tool can process multiple file geodatabases at once. A separate text file report will be created for each geodatabase. The toolbox was created using ArcGIS Pro 3.7.11.

For more information about this and other related tools, explore the Geospatial Data Curation toolkit

This feature layer depicts land use within northeastern Illinois broken out into 57 categories. This dataset is an update of the 2018 parcel-based Land Use Inventory and the primary focus was on parcels whose assessment records or geometry had changed between 2018 and 2020, suggesting a change in land use. Parcels were dissolved on common land use types, and polygons were generated for non-parcel areas (e.g. road rights-of-way) and assigned a generic “non-parcel” category.Download the data from the CMAP Data Hub.Supporting metadata and documentation for the 2020 Land Use Inventory for Northeastern Illinois:

2020 Land Use Inventory Classification Schema provides a full description of all land use categories. 2020 Land Use Inventory Geodatabase Schema provides a description of LUI attributes and domains. 2020 Land Use Inventory Metadata LANDUSE lookup .csv table to support shapefile downloads.

More information can be found on CMAP's Land Use Inventory webpage.

Displays data from CADASTRAL.LEGAL_ROW_PLGN_PV. The layer will not display when zoomed out beyond 1:50,000. Attribute is associated with geodatabase domain SUBDIVISION_FEASYM_CODE. Only hierarchy of assignment is alleys (9) over other rowadj types (2, 3, 4, 8). L_FEA_SYM is a numeric code that identifies polygon features by type:1 - lot2 - right of way3 - rowadj (ordinance)4 - rowadj (deed)5 - other agency property6 - easement7 - tract8 - court cause (SCC) 9 - row (alleys) 10 - row (railroads)11 - water bodies 40 - private road.Updated weekly.

Contour2006 is a Polyline Shapefile of contours generated from LiDAR data for the San Jose Phase 3 project of Santa Clara County, Ca. The purpose of the bare-earth LiDAR Point and Breakline data is to provide ground surface data and one-foot (Valley Area) and five-foot (Mountain Areas) contour generation, and the delineation of watercourse ( Top of Bank ). LAS format files, raw LiDAR data in its native format, classified bare-earth LiDAR DEM and photogrammetrically derived breaklines generated from LiDAR Intensity stereo-pairs. Breakline, Top of Bank, and contour files in ESRI personal geodatabase format, Microstation V8 .dgn format, and AutoCAD 2004 formats for the San Jose Phase 3 project of Santa Clara County, Ca. It is primarily used to model elevation and as a reference layer. Contour2006 has the following fields:

OBJECTID_1: Unique identifier automatically generated by Esri type: OID, length: 4, domain: none

TYPE: The type of contour line type: String, length: 25, domain: none

ELEVATION: The elevation of the contour line - in feet type: Double, length: 8, domain: none

Shape_Leng: The length of the shape - in feet type: Double, length: 8, domain: none

TILE_ID: The unique ID associated with the tile type: String, length: 9, domain: none

ObjectID: Unique identifier automatically generated by Esri type: Integer, length: 4, domain: none

Shape: Field that stores geographic coordinates associated with feature type: Geometry, length: 4, domain: none

Shape_Length: The length of the shape - in feet type: Double, length: 0, domain: none

USGS Structures from The National Map (TNM) consists of data to include the name, function, location, and other core information and characteristics of selected manmade facilities across all US states and territories. The types of structures collected are largely determined by the needs of disaster planning and emergency response, and homeland security organizations. Structures currently included are: School, School:Elementary, School:Middle, School:High, College/University, Technical/Trade School, Ambulance Service, Fire Station/EMS Station, Law Enforcement, Prison/Correctional Facility, Post Office, Hospital/Medical Center, Cabin, Campground, Cemetery, Historic Site/Point of Interest, Picnic Area, Trailhead, Vistor/Information Center, US Capitol, State Capitol, US Supreme Court, State Supreme Court, Court House, Headquarters, Ranger Station, White House, and City/Town Hall. Structures data are designed to be used in general mapping and in the analysis of structure related activities using geographic information system technology. Included is a feature class of preliminary building polygons provided by FEMA, USA Structures. The National Map structures data is commonly combined with other data themes, such as boundaries, elevation, hydrography, and transportation, to produce general reference base maps. The National Map viewer allows free downloads of public domain structures data in either Esri File Geodatabase or Shapefile formats. For additional information on the structures data model, go to https://www.usgs.gov/ngp-standards-and-specifications/national-map-structures-content.

The USGS Transportation service from The National Map (TNM) is based on TIGER/Line data provided through U.S. Census Bureau and road data from U.S. Forest Service. Some of the TIGER/Line data includes limited corrections done by USGS. Transportation data consists of roads, railroads, trails, airports, and other features associated with the transport of people or commerce. The data include the name or route designator, classification, and location. Transportation data support general mapping and geographic information system technology analysis for applications such as traffic safety, congestion mitigation, disaster planning, and emergency response. The National Map transportation data is commonly combined with other data themes, such as boundaries, elevation, hydrography, and structures, to produce general reference base maps. The National Map Download Client allows free downloads of public domain transportation data in either Esri File Geodatabase or Shapefile formats. For additional information on the transportation data model, go to https://nationalmap.gov/transport.html.

USGS Structures from The National Map (TNM) consists of data to include the name, function, location, and other core information and characteristics of selected manmade facilities. The types of structures collected are largely determined by the needs of disaster planning and emergency response, and homeland security organizations. Structures currently being collected are: School, College/University, Fire Station/EMS Station, Law Enforcement, Prison/Correctional Facility, State Capitol, Hospital/Medical Center, Ambulance Services, Cemetery, and Post Office. Structures data are designed to be used in general mapping and in the analysis of structure related activities using geographic information system technology. The National Map structures data is commonly combined with other data themes, such as boundaries, elevation, hydrography, and transportation, to produce general reference base maps. The National Map viewer allows free downloads of public domain structures data in either Esri File Geodatabase or Shapefile formats. For additional information on the structures data model, go to https://nationalmap.gov/structures.html.

USGS Structures from The National Map consists of data to include the name, function, location, and other core information and characteristics of selected manmade facilities. The types of structures collected are largely determined by the needs of disaster planning and emergency response, and homeland security organizations. Structures currently being collected are: School, Technical/Trade School, College/University, Fire Station/EMS Station, Law Enforcement/Police Station, Prison/Correctional Facility, State Capitol, Hospital/Medical Center, Ambulance Service, Cemetery, Post Office, Campground, Trailhead, and Visitor/Information Center. Structures data are designed to be used in general mapping and in the analysis of structure related activities using geographic information system technology. The National Map structures data is commonly combined with other data themes, such as boundaries, elevation, hydrography, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain structures data in either Esri File Geodatabase or Shapefile formats. For additional information on the structures data model, go to https://www.usgs.gov/core-science-systems/ngp/tnm-corps/structures. See https://apps.nationalmap.gov/help/ for assistance with The National Map viewer, download client, services, or metadata. Data Refreshed January, 2025

The Watershed Boundary Dataset (WBD) from The National Map (TNM) defines the perimeter of drainage areas formed by the terrain and other landscape characteristics. The drainage areas are nested within each other so that a large drainage area, such as the Upper Mississippi River, is composed of multiple smaller drainage areas, such as the Wisconsin River. Each of these smaller areas can further be subdivided into smaller and smaller drainage areas. The WBD uses six different levels in this hierarchy, with the smallest averaging about 30,000 acres. The WBD is made up of polygons nested into six levels of data respectively defined by Regions, Subregions, Basins, Subbasins, Watersheds, and Subwatersheds. For additional information on the WBD, go to https://nhd.usgs.gov/wbd.html. The USGS National Hydrography Dataset (NHD) service is a companion dataset to the WBD. The NHD is a comprehensive set of digital spatial data that encodes information about naturally occurring and constructed bodies of surface water (lakes, ponds, and reservoirs), paths through which water flows (canals, ditches, streams, and rivers), and related entities such as point features (springs, wells, stream gages, and dams). The information encoded about these features includes classification and other characteristics, delineation, geographic name, position and related measures, a "reach code" through which other information can be related to the NHD, and the direction of water flow. The network of reach codes delineating water and transported material flow allows users to trace movement in upstream and downstream directions. In addition to this geographic information, the dataset contains metadata that supports the exchange of future updates and improvements to the data. The NHD is available nationwide in two seamless datasets, one based on 1:24,000-scale maps and referred to as high resolution NHD, and the other based on 1:100,000-scale maps and referred to as medium resolution NHD. Additional selected areas in the United States are available based on larger scales, such as 1:5,000-scale or greater, and referred to as local resolution NHD. For more information on the NHD, go to https://nhd.usgs.gov/index.html. Hydrography data from The National Map supports many applications, such as making maps, geocoding observations, flow modeling, data maintenance, and stewardship. Hydrography data is commonly combined with other data themes, such as boundaries, elevation, structures, and transportation, to produce general reference base maps. The National Map viewer allows free downloads of public domain WBD and NHD data in either Esri File or Personal Geodatabase, or Shapefile formats. The Watershed Boundary Dataset is being developed under the leadership of the Subcommittee on Spatial Water Data, which is part of the Advisory Committee on Water Information (ACWI) and the Federal Geographic Data Committee (FGDC). The USDA Natural Resources Conservation Service (NRCS), along with many other federal agencies and national associations, have representatives on the Subcommittee on Spatial Water Data. As watershed boundary geographic information systems (GIS) coverages are completed, statewide and national data layers will be made available via the Geospatial Data Gateway to everyone, including federal, state, local government agencies, researchers, private companies, utilities, environmental groups, and concerned citizens. The database will assist in planning and describing water use and related land use activities. Resources in this dataset:Resource Title: Watershed Boundary Dataset (WBD). File Name: Web Page, url: https://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/water/watersheds/dataset/?cid=nrcs143_021630 Web site for the Watershed Boundary Dataset (WBD), including links to:

Review Data Availability (Status Maps) Obtain Data by State, County, or Other Area Obtain Seamless National Data offsite link image
Geospatial Data Tools National Technical and State Coordinators Information about WBD dataset

USGS Structures from The National Map consists of data to include the name, function, location, and other core information and characteristics of selected manmade facilities. The types of structures collected are largely determined by the needs of disaster planning and emergency response, and homeland security organizations. Structures currently being collected are: School, Technical/Trade School, College/University, Fire Station/EMS Station, Law Enforcement/Police Station, Prison/Correctional Facility, State Capitol, Hospital/Medical Center, Ambulance Service, Cemetery, Post Office, Campground, Trailhead, and Visitor/Information Center. Structures data are designed to be used in general mapping and in the analysis of structure related activities using geographic information system technology. The National Map structures data is commonly combined with other data themes, such as boundaries, elevation, hydrography, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain structures data in either Esri File Geodatabase or Shapefile formats. For additional information on the structures data model, go to http://nationalmap.gov/structures.html.

The USGS Governmental Unit Boundaries service from The National Map (TNM) represents major civil areas for the Nation, including States or Territories, counties (or equivalents), Federal and Native American areas, congressional districts, minor civil divisions, incorporated places (such as cities and towns), and unincorporated places. Boundaries data are useful for understanding the extent of jurisdictional or administrative areas for a wide range of applications, including mapping or managing resources, and responding to natural disasters. Boundaries data also include extents of forest, grassland, park, wilderness, wildlife, and other reserve areas useful for recreational activities, such as hiking and backpacking. Boundaries data are acquired from a variety of government sources. The data represents the source data with minimal editing or review by USGS. Please refer to the feature-level metadata for information on the data source. The National Map boundaries data is commonly combined with other data themes, such as elevation, hydrography, structures, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain boundaries data in either Esri File Geodatabase or Shapefile formats. See https://apps.nationalmap.gov/help/ for assistance with The National Map viewer, download client, services, or metadata.

The National Hydrography Dataset (NHD), found in the A-16 National Geospatial Data Asset Portfolio, contains information related to naturally occurring and constructed bodies of surface water in the United States. This United States Geological Survey service from The National Map is a comprehensive set of digital spatial data that encodes information about lakes, ponds, and reservoirs, paths through which water flows (canals, ditches, streams, and rivers), and related entities such as point features (springs, wells, stream gauges, and dams). The information encoded about these features includes classification and other characteristics, delineation, geographic name, position and related measures, a "reach code" through which other information can be related to the NHD, and the direction of water flow. The network of reach codes delineating water and transported material flow allows users to trace movement in upstream and downstream directions. The NHD is available nationwide in two seamless datasets, one based on a neighborhood or larger scale (1:24,000) and referred to as high resolution NHD, and the other based on a city scale (1:100,000) and referred to as medium resolution NHD. The National Map allows free downloads of public domain NHD data in either Esri File Geodatabase or Shapefile formats. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.Thumbnail source image courtesy of: Sharon Mollerus

The USGS Elevation Contours service from The National Map (TNM) consists of contours generated for the conterminous United States from 1- and 1/3 arc-second elevation data. Small scale contours derived from 1 arc-second data are displayed at scales ranging from 1:577K to 1:72K in The National Map viewer. Contour intervals are 100 foot between 1:577K and 1:144K, and 50 foot at 1:72K. Large scale contours derived from 1/3 arc-second data are displayed at 1:50K (and larger). Large scale contour intervals are variable across the United States depending on complexity of topography. The National Map viewer allows free downloads of public domain contour data in either Esri File Geodatabase or Shapefile formats. The 3D Elevation Program (3DEP) provides elevation data for The National Map and basic elevation information for earth science studies and mapping applications. Scientists and resource managers use elevation data for global change research, hydrologic modeling, resource monitoring, mapping and visualization, and many other applications. For additional information on 3DEP, go to http://nationalmap.gov/3DEP/.

The USGS National Hydrography Dataset (NHD) service from The National Map is a comprehensive set of digital spatial data that encodes information about naturally occurring and constructed bodies of surface water (lakes, ponds, and reservoirs), paths through which water flows (canals, ditches, streams, and rivers), and related entities such as point features (springs, wells, stream gages, and dams). The information encoded about these features includes classification and other characteristics, delineation, geographic name, position and related measures, a "reach code" through which other information can be related to the NHD, and the direction of water flow. The network of reach codes delineating water and transported material flow allows users to trace movement in upstream and downstream directions. In addition to this geographic information, the dataset contains metadata that supports the exchange of future updates and improvements to the data. The NHD is available nationwide in two seamless datasets, one based on 1:24,000 (or larger) scale and referred to as high resolution NHD, and the other based on 1:100,000 scale and referred to as medium resolution NHD. The NHD from The National Map supports many applications, such as making maps, geocoding observations, flow modeling, data maintenance, and stewardship. The NHD is commonly combined with other data themes, such as boundaries, elevation, structures, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain NHD data in either Esri File Geodatabase or Shapefile formats. For additional information on the NHD, go to https://www.usgs.gov/national-hydrography/national-hydrography-dataset. See https://apps.nationalmap.gov/help/ for assistance with The National Map viewer, download client, services, or metadata. Data Refreshed January, 2024.

USGS Structures from The National Map consists of data to include the name, function, location, and other core information and characteristics of selected manmade facilities. The types of structures collected are largely determined by the needs of disaster planning and emergency response, and homeland security organizations. Structures currently being collected are: School, Technical/Trade School, College/University, Fire Station/EMS Station, Law Enforcement/Police Station, Prison/Correctional Facility, State Capitol, Hospital/Medical Center, Ambulance Service, Cemetery, Post Office, Campground, Trailhead, and Visitor/Information Center. Structures data are designed to be used in general mapping and in the analysis of structure related activities using geographic information system technology. The National Map structures data is commonly combined with other data themes, such as boundaries, elevation, hydrography, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain structures data in either Esri File Geodatabase or Shapefile formats. For additional information on the structures data model, go to https://www.usgs.gov/core-science-systems/ngp/tnm-corps/structures. See https://apps.nationalmap.gov/help/ for assistance with The National Map viewer, download client, services, or metadata. Data Refreshed January, 2025

The USGS National Hydrography Dataset (NHD) service from The National Map is a comprehensive set of digital spatial data that encodes information about naturally occurring and constructed bodies of surface water (lakes, ponds, and reservoirs), paths through which water flows (canals, ditches, streams, and rivers), and related entities such as point features (springs, wells, stream gages, and dams). The information encoded about these features includes classification and other characteristics, delineation, geographic name, position and related measures, a "reach code" through which other information can be related to the NHD, and the direction of water flow. The network of reach codes delineating water and transported material flow allows users to trace movement in upstream and downstream directions. In addition to this geographic information, the dataset contains metadata that supports the exchange of future updates and improvements to the data. The NHD is available nationwide in two seamless datasets, one based on 1:24,000 (or larger) scale and referred to as high resolution NHD, and the other based on 1:100,000 scale and referred to as medium resolution NHD. The NHD from The National Map supports many applications, such as making maps, geocoding observations, flow modeling, data maintenance, and stewardship. The NHD is commonly combined with other data themes, such as boundaries, elevation, structures, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain NHD data in either Esri File Geodatabase or Shapefile formats. For additional information on the NHD, go to https://www.usgs.gov/national-hydrography/national-hydrography-dataset. See https://apps.nationalmap.gov/help/ for assistance with The National Map viewer, download client, services, or metadata.Use Constraints: _ 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.

In 2010, the Alaska Regional Director and Alaska Leadership Council directed all parks to complete a geospatial layer of installations and keep it up to date for use in cumulative impacts analysis. The AKR Installations Geodatabase is a centralized data repository that supports a regionally consistent approach useful for NPS permitting and resource management. By supporting the 2010 initiatives for strengthening NPS wilderness stewardship, this system can inform NEPA analyses, help parks track accountability for maintaining and removing installations, and provide critical information for wilderness character monitoring. This AKR Installations Geodatabase, developed and stewarded by the AKR GIS Team, is available for upkeep by each park through its designated Installations Point-of-Contact (POC) and supporting GIS POC. The Installations POC is generally the park coordinator for wilderness, compliance, and/or permitting while the GIS POC is someone who can assist with organizing and preparing the geospatial data for inclusion in the AKR Installations Geodatabase. The AKR Installations Geodatabase contains four point‐type feature classes: Instrumentation Installations (INSTRUMENTATION), Marker Installations (MARKER), Communication Installations (COMMUNICATION), and Generic Installation Point Installations (GENERIC INSTALLATION POINT). Each feature class in the geodatabase is designed to store a specific type of installation data and represent that installation data as a point feature in ArcGIS. To facilitate data entry, viewing, and analysis the non‐spatial attribute fields contained in each feature class have been standardized. The Installations User Guide was developed as a reference to introduce the NPS Alaska Region Installation geodatabase and provide guidance for installation data entry and record management in this system. It is recommended that the Installations User Guide be reviewed prior to populating the NPS Alaska Region Installations geodatabase.The COMMUNICATION feature class is designed to contain records for installations of stand‐alone communication relay equipment (e.g. radio repeaters, cell phone towers). Installations in the COMMUNICATION feature class differ from those in the INSTRUMENTATION feature class as they serve to transmit data, not collect or record data for scientific purposes. Communication‐related equipment associated with a station‐type installation managed in the INSTRUMENTATION feature class (i.e. continuous GPS station, seismic station, precipitation station, SNOTEL station, snow course station, weather station) are not considered to be stand‐alone. Please review the COMMUNICATION feature class data model (Section 12) of the Installations User Guide to gain a general understanding of its structure and data requirements. Table 10 and the domain values assigned in the data model’s Installation_Subtype field may further clarify the types of items relevant to this feature class.The GENERIC INSTALLATION POINT feature class is designed to contain records for installations the user deems relevant to the cumulative effects analysis process, but are not appropriate for inclusion in the INSTRUMENTATION, MARKER, or COMMUNICATION features classes at present time. The GENERIC INSTALLATION POINT feature class is intended to serve the purpose of a temporary placeholder for installation data while NPS data standards and the NPS Alaska Region Installations geodatabase evolve. Please review the GENERIC INSTALLATION POINT feature class data model (Section 12) of the Installations User Guide to gain a general understanding of its structure and data requirements. Table 11 may further clarify the types of items relevant to this feature class. Installation data outside of Table 11 items may also be included, but please remember that all records contained in this feature class will be represented as points in ArcGIS. OHV trails and maintained foot trails are better represented as line features in ArcGIS and have therefore not been marked for inclusion in the GENERIC INSTALLATION POINT feature class.The INSTRUMENTATION feature class is designed to contain records for installations of equipment that collect or record data for scientific purposes. Please review the INSTRUMENTATION feature class data model (Section 12) of the Installations User Guide to gain a general understanding of its structure and data requirements. Table 2 and the domain values assigned in the data model’s Installation_Subtype field may further clarify the types of items relevant to this feature class.The MARKER feature class is designed to contain records for installations that serve to mark a location of interest. Please review the MARKER feature class data model (Section 12) of the Installations User Guide to gain a general understanding of its structure and data requirements. Table 7 and the domain values assigned in the data model’s the Installation_Subtype field may further clarify the types of items relevant to this feature class. The MARKER feature class in the NPS Alaska Region Installations geodatabase was developed to manage installation data relevant to the cumulative effects analysis process and is not intended to replace the NPS Survey Monumentation Data Standard for the distribution of survey monumentation data to enterprise GIS systems.The corresponding NPS DataStore on Integrated Resource Management Applications (IRMA) reference is:AKR Science in Wilderness Installations PUBLIC

USGS Structures from The National Map consists of data to include the name, function, location, and other core information and characteristics of selected manmade facilities. The types of structures collected are largely determined by the needs of disaster planning and emergency response, and homeland security organizations. Structures currently being collected are: School, Technical/Trade School, College/University, Fire Station/EMS Station, Law Enforcement/Police Station, Prison/Correctional Facility, State Capitol, Hospital/Medical Center, Ambulance Service, Cemetery, Post Office, Campground, Trailhead, and Visitor/Information Center. Structures data are designed to be used in general mapping and in the analysis of structure related activities using geographic information system technology. The National Map structures data is commonly combined with other data themes, such as boundaries, elevation, hydrography, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain structures data in either Esri File Geodatabase or Shapefile formats. For additional information on the structures data model, go to https://www.usgs.gov/core-science-systems/ngp/tnm-corps/structures. See https://apps.nationalmap.gov/help/ for assistance with The National Map viewer, download client, services, or metadata. Data Refreshed January, 2025

Please use 3DHP for updated data The USGS National Hydrography Dataset (NHD) service from The National Map is a comprehensive set of digital spatial data that encodes information about naturally occurring and constructed bodies of surface water (lakes, ponds, and reservoirs), paths through which water flows (canals, ditches, streams, and rivers), and related entities such as point features (springs, wells, stream gages, and dams). The information encoded about these features includes classification and other characteristics, delineation, geographic name, position and related measures, a "reach code" through which other information can be related to the NHD, and the direction of water flow. The network of reach codes delineating water and transported material flow allows users to trace movement in upstream and downstream directions. In addition to this geographic information, the dataset contains metadata that supports the exchange of future updates and improvements to the data. The NHD is available nationwide in two seamless datasets, one based on 1:24,000 (or larger) scale and referred to as high resolution NHD, and the other based on 1:100,000 scale and referred to as medium resolution NHD. The NHD from The National Map supports many applications, such as making maps, geocoding observations, flow modeling, data maintenance, and stewardship. The NHD is commonly combined with other data themes, such as boundaries, elevation, structures, and transportation, to produce general reference base maps. The National Map download client allows free downloads of public domain NHD data in either Esri File Geodatabase or Shapefile formats. For additional information on the NHD, go to https://www.usgs.gov/national-hydrography/national-hydrography-dataset. See https://apps.nationalmap.gov/help/ for assistance with The National Map viewer, download client, services, or metadata. Data Refreshed January, 2024.