Why are two different file naming conventions used in distribution of 3D Elevation Program (3DEP) DEM national products?

Updated digital elevation model (DEM) datasets are now renamed with a different naming convention to include resolution and format in the file name. This prevents users from accidentally overwriting existing data with the same file names across multiple resolutions and formats.

For example, an older dataset named n44w071.zip has been replaced with the file name USGS_NED_13_n44w071_GridFloat.zip This is 1/3 arc-second elevation data in GridFloat format for the 1x1 degree tile of n44w071.

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Where can I find a 3D Elevation Program (3DEP) DEM status map and get information on recent updates?

Status maps showing 3D Elevation Program (3DEP) product availability and recent updates are on the 3DEP Product Availability site. Areas containing recent updates are refreshed on a monthly basis. Download spatial metadata shapefiles showing the updated areas for each product from the 3DEP Product Metadata site. Acquire updated products through...

What is Lidar data and where can I download it?

Lidar data are available through The National Map Download Client . Click the “How To” link at the top of the viewer for detailed instructions on how to find and download data. Light Detection and Ranging (LIDAR) is a technology similar to RADAR that can be used to create high-resolution digital elevation models (DEMs) with vertical accuracy as...

What are the projection, horizontal and vertical datum, and resolution for 3D Elevation Program (3DEP) standard DEMs?

All 3DEP seamless DEMs are provided in geographic coordinates (longitude and latitude) in units of decimal degrees, horizontally referenced on the North American Datum of 1983 (NAD83). All elevation values are in units of meters, typically referenced to the North American Vertical Datum of 1988 (NAVD88), although the National Geodetic Vertical...

Is there a difference between 3D Elevation Program (3DEP) DEM data and lidar data?

Yes, lidar data are represented as a cloud of variably spaced point locations (x,y,z) of any terrestrial target reflecting the laser pulse. In addition to bare-earth, the point cloud will typically include buildings, trees, towers, and powerlines. 3DEP DEMs are raster surfaces of bare-earth elevation values sampled at uniform horizontal increments...

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...

What are digital elevation models (DEMs)?

USGS Digital elevation models (DEMs) are arrays of regularly spaced elevation values referenced horizontally either to a Universal Transverse Mercator (UTM) projection or to a geographic coordinate system. The grid cells are spaced at regular intervals along south to north profiles that are ordered from west to east. The USGS acquires bare-earth...
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Date published: October 23, 2019

USGS Digital Elevation Models (DEM) Switching to New Distribution Format

In support of ongoing efforts to provide efficient, cloud ready, open data formats, the U.S. Geological Survey National Geospatial Program is announcing plans to migrate its 3D Elevation Program (3DEP) Digital Elevation Models (DEM) to a new data delivery format called Cloud Optimized Geotiff (COG) during the first half of fiscal year 2020.

Date published: February 7, 2019

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 repository.

Date published: October 30, 2018

USGS Topo Base Map Refreshed and Other Updates

The “USGS Topo Base Map” service named “USGS Topo” has been refreshed with new data and design changes. In addition, several of the “Data Availability”, or “Data Index” services have new cloud hosted URLs.

Date published: August 8, 2018

New Elevation Map Service Available From the USGS 3D Elevation Program

The USGS 3D Elevation Program (3DEP) announces the availability of a new dynamic map service.

Date published: June 26, 2018

The 3D Elevation Program Distributing Lidar Data in LAZ Format

In support of ongoing efforts to provide efficient, cloud ready, open data formats for the use of lidar data, the USGS National Geospatial Program and its associated 3D Elevation Program is transitioning all of its lidar data distribution files to LAZ format by September 30, 2018.

Date published: September 5, 2016


It’s not a radar for liars, it’s this week’s Earthword...

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November 7, 2018

3D model of Pu‘u ‘Ō‘ō's crater

This 3D model of Pu‘u ‘Ō‘ō's crater was created from thermal images during an overflight of the cone. The deepest portion of the crater is about 320 meters (1050 feet) below the crater floor that existed prior to April 30.

video thumbnail: Elevation
April 30, 2012


The National Elevation Dataset (NED) is the primary elevation data product produced and distributed by the USGS National 3D Elevation Program (3DEP). The NED provides seamless raster elevation data of the conterminous United States, Alaska, Hawaii, and the island territories. The NED is derived from diverse source data sets that are processed to a specification with a

Digital topography from high-resolution digital elevation dataset u...

Digital topography from high-resolution digital elevation dataset u...

View of Mount Baker from the west. Summit area draped with aerial imagery from National Agriculture Imagery Program (NAIP) collected in September 2015. Digital topography from High-resolution digital elevation dataset for Mount Baker and vicinity, Washington, based on lidar surveys of 2015: U.S. Geological Survey data release,

Screen shot of elevation aspect map rendered in the 3DEP Demonstration Elevation Viewer

3DEP Viewer, elevation aspect

Elevation aspect map rendered in the 3DEP Demonstration Elevation Viewer.