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What is the projection, horizontal datum, vertical datum, and resolution for a USGS digital elevation model (DEM)?

Projection:  3DEP DEMS have different projections/coordinate systems depending on the product:

  • 1/3-, 1-, and 2-arc-second (also the discontinued 1/9-arc-second) DEMs are not projected.  They are all in geographic coordinates (latitude/longitude).
  • 5-meter DEMs (Alaska only) are Alaska Albers Equal Area.
  • 1-meter DEMs are in Universal Transverse Mercator (UTM).
  • Original Product Resolution (OPR) DEMs – projection varies.
  • The coordinate system and projection information for ALL DEMs are in each DEM file header; GIS software should detect them automatically.

Horizontal Datum:  The North American Datum of 1983 (NAD83)  

Vertical Datum:  Typically the North American Vertical Datum of 1988 (NAVD88), although the National Geodetic Vertical Datum of 1929 (NGVD29) and local reference datums are used in some areas outside of the conterminous United States. For Hawaii, Puerto Rico, U.S. Virgin Islands, and Pacific Island territories, the vertical datum is typically referenced to local mean sea level.    

Resolution:  The conterminous United States is available at horizontal resolutions of  

  • 1-arc-second (~30 meters):  full coverage  
  • 1/3-arc-second (~10 meters): full coverage   
  • 1/9-arc-second (~3 meters): partial coverage  
  • 1-meter: partial coverage   

Learn more: 

Related Content

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Example visualization of model output

How do I report errors in 3D Elevation Program (3DEP) elevation data?

If you think you’ve found an error in USGS elevation data, please send an email to tnm_help@usgs.gov. We will add the reported information to our "Digital Elevation Model Issues" data log for further analysis and possible correction. Spikes, pits, seam-line anomalies, and other data errors are of concern to us. We are working to correct or minimize known issues, but it will take some time. Errors...

link

How do I report errors in 3D Elevation Program (3DEP) elevation data?

If you think you’ve found an error in USGS elevation data, please send an email to tnm_help@usgs.gov. We will add the reported information to our "Digital Elevation Model Issues" data log for further analysis and possible correction. Spikes, pits, seam-line anomalies, and other data errors are of concern to us. We are working to correct or minimize known issues, but it will take some time. Errors...

Learn More
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excerpt of lidar imagery in Columbia Gorge

What is the coverage of 3D Elevation Program (3DEP) DEMs?

Elevation products are summarized on our 3-D Elevation (3DEP) Products and Services website. View detailed availability maps (status graphics) through several sites: The National Map Download Client – Click “Show” below each elevation product Lidar Availability Viewer - Lidar point cloud only LidarExplorer – Lidar point cloud only DEM Availability Viewer - 1 meter DEMs only Learn more:  What is...

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What is the coverage of 3D Elevation Program (3DEP) DEMs?

Elevation products are summarized on our 3-D Elevation (3DEP) Products and Services website. View detailed availability maps (status graphics) through several sites: The National Map Download Client – Click “Show” below each elevation product Lidar Availability Viewer - Lidar point cloud only LidarExplorer – Lidar point cloud only DEM Availability Viewer - 1 meter DEMs only Learn more:  What is...

Learn More
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Lidar image

What is the difference between lidar data and a digital elevation model (DEM)?

Light detection and ranging (lidar) data are collected from aircraft using sensors that detect the reflections of a pulsed laser beam. The reflections are recorded as millions of individual points, collectively called a “point cloud,” that represent the 3D positions of objects on the surface including buildings, vegetation, and the ground. Digital elevation models (DEMs) are one of many products...

link

What is the difference between lidar data and a digital elevation model (DEM)?

Light detection and ranging (lidar) data are collected from aircraft using sensors that detect the reflections of a pulsed laser beam. The reflections are recorded as millions of individual points, collectively called a “point cloud,” that represent the 3D positions of objects on the surface including buildings, vegetation, and the ground. Digital elevation models (DEMs) are one of many products...

Learn More
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3D Elevation Program—Federal best practices

The goal of the 3D Elevation Program (3DEP) is to complete nationwide data acquisition in 8 years, by 2023, to provide the first-ever national baseline of consistent high-resolution three-dimensional data—including bare earth elevations and three-dimensional point clouds—collected in a timeframe of less than a decade. Successful implementation of 3DEP depends on partnerships and the development an
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The 3D Elevation Program—Supporting California's Economy

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Core Science Systems Mission Area, National Geospatial Program, 3D Elevation Program

Coastal National Elevation Database

The Coastal National Elevation Database (CoNED) Applications Project develops enhanced topographic (land elevation) and bathymetric (water depth) datasets that serve as valuable resources for coastal hazards research (Danielson and others, 2016; Thatcher and others, 2016). These datasets are used widely for mapping inundation zones from riverine flood events, hurricanes, and sea-level rise and for
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Flood-damage reduction in the United States has been a longstanding but elusive societal goal. The national strategy for reducing flood damage has shifted over recent decades from a focus on construction of flood-control dams and levee systems to a three-pronged strategy to (1) improve the design and operation of such structures, (2) provide more accurate and accessible flood forecasting, and (3)
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The 3D Elevation Program—Landslide recognition, hazard assessment, and mitigation support

The U.S. Geological Survey (USGS) Landslide Hazards Program conducts landslide hazard assessments, pursues landslide investigations and forecasts, provides technical assistance to respond to landslide emergencies, and engages in outreach. All of these activities benefit from the availability of high-resolution, three-dimensional (3D) elevation information in the form of light detection and ranging
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USGS 3DEP Lidar Point Cloud Now Available as Amazon Public Dataset

The USGS 3D Elevation Program (3DEP) is excited to announce the availability of a new way to access and process lidar point cloud data from the 3DEP...

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New Elevation for Nation’s Highest Peak

A new, official height for Denali has been measured at 20,310 feet, just 10 feet less than the previous elevation of 20,320 feet which was established...

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Related Content

  • FAQ
    link
    Example visualization of model output

    How do I report errors in 3D Elevation Program (3DEP) elevation data?

    If you think you’ve found an error in USGS elevation data, please send an email to tnm_help@usgs.gov. We will add the reported information to our "Digital Elevation Model Issues" data log for further analysis and possible correction. Spikes, pits, seam-line anomalies, and other data errors are of concern to us. We are working to correct or minimize known issues, but it will take some time. Errors...

    link

    How do I report errors in 3D Elevation Program (3DEP) elevation data?

    If you think you’ve found an error in USGS elevation data, please send an email to tnm_help@usgs.gov. We will add the reported information to our "Digital Elevation Model Issues" data log for further analysis and possible correction. Spikes, pits, seam-line anomalies, and other data errors are of concern to us. We are working to correct or minimize known issues, but it will take some time. Errors...

    Learn More
    link
    excerpt of lidar imagery in Columbia Gorge

    What is the coverage of 3D Elevation Program (3DEP) DEMs?

    Elevation products are summarized on our 3-D Elevation (3DEP) Products and Services website. View detailed availability maps (status graphics) through several sites: The National Map Download Client – Click “Show” below each elevation product Lidar Availability Viewer - Lidar point cloud only LidarExplorer – Lidar point cloud only DEM Availability Viewer - 1 meter DEMs only Learn more:  What is...

    link

    What is the coverage of 3D Elevation Program (3DEP) DEMs?

    Elevation products are summarized on our 3-D Elevation (3DEP) Products and Services website. View detailed availability maps (status graphics) through several sites: The National Map Download Client – Click “Show” below each elevation product Lidar Availability Viewer - Lidar point cloud only LidarExplorer – Lidar point cloud only DEM Availability Viewer - 1 meter DEMs only Learn more:  What is...

    Learn More
    link
    Lidar image

    What is the difference between lidar data and a digital elevation model (DEM)?

    Light detection and ranging (lidar) data are collected from aircraft using sensors that detect the reflections of a pulsed laser beam. The reflections are recorded as millions of individual points, collectively called a “point cloud,” that represent the 3D positions of objects on the surface including buildings, vegetation, and the ground. Digital elevation models (DEMs) are one of many products...

    link

    What is the difference between lidar data and a digital elevation model (DEM)?

    Light detection and ranging (lidar) data are collected from aircraft using sensors that detect the reflections of a pulsed laser beam. The reflections are recorded as millions of individual points, collectively called a “point cloud,” that represent the 3D positions of objects on the surface including buildings, vegetation, and the ground. Digital elevation models (DEMs) are one of many products...

    Learn More
  • Multimedia
    link
    link
  • Publications

    3D Elevation Program—Federal best practices

    The goal of the 3D Elevation Program (3DEP) is to complete nationwide data acquisition in 8 years, by 2023, to provide the first-ever national baseline of consistent high-resolution three-dimensional data—including bare earth elevations and three-dimensional point clouds—collected in a timeframe of less than a decade. Successful implementation of 3DEP depends on partnerships and the development an
    By
    National Geospatial Program, 3D Elevation Program

    The 3D Elevation Program—Supporting California's Economy

    IntroductionCalifornia faces unprecedented challenges presented by shifting weather patterns that are defining a “new normal.” The result has been extreme weather events, prolonged drought, flooding, and debris flows. These conditions drive severe tree mortality, increase wildfire occurrence and intensity, reduce water availability, and hasten subsidence in groundwater basins. Collectively, these
    By
    Core Science Systems Mission Area, National Geospatial Program, 3D Elevation Program

    Coastal National Elevation Database

    The Coastal National Elevation Database (CoNED) Applications Project develops enhanced topographic (land elevation) and bathymetric (water depth) datasets that serve as valuable resources for coastal hazards research (Danielson and others, 2016; Thatcher and others, 2016). These datasets are used widely for mapping inundation zones from riverine flood events, hurricanes, and sea-level rise and for
    By
    Earth Resources Observation and Science Center, Earth Resources Observation and Science (EROS) Center

    The 3D Elevation Program—Flood risk management

    Flood-damage reduction in the United States has been a longstanding but elusive societal goal. The national strategy for reducing flood damage has shifted over recent decades from a focus on construction of flood-control dams and levee systems to a three-pronged strategy to (1) improve the design and operation of such structures, (2) provide more accurate and accessible flood forecasting, and (3)
    By
    Groundwater and Streamflow Information Program, National Geospatial Program, 3D Elevation Program

    The 3D Elevation Program—Landslide recognition, hazard assessment, and mitigation support

    The U.S. Geological Survey (USGS) Landslide Hazards Program conducts landslide hazard assessments, pursues landslide investigations and forecasts, provides technical assistance to respond to landslide emergencies, and engages in outreach. All of these activities benefit from the availability of high-resolution, three-dimensional (3D) elevation information in the form of light detection and ranging
    By
    Natural Hazards Mission Area, Landslide Hazards Program, National Geospatial Program, Geologic Hazards Science Center, 3D Elevation Program
  • News
    link

    USGS 3DEP Lidar Point Cloud Now Available as Amazon Public Dataset

    The USGS 3D Elevation Program (3DEP) is excited to announce the availability of a new way to access and process lidar point cloud data from the 3DEP...

    Read Article
    link

    Keeping Current with Map Services Made Easier

    The National Map provides a new Simple Notification Service and has new URLs for some of its thematic cartographic map services.

    Read Article
    link

    The 3D Elevation Program and America's Infrastructure

    The USGS is seeing a dramatic increase in the use of 3D geospatial data for infrastructure planning, modeling and construction

    Read Article
    link

    New Elevation for Nation’s Highest Peak

    A new, official height for Denali has been measured at 20,310 feet, just 10 feet less than the previous elevation of 20,320 feet which was established...

    Read Article