USGS 3DEP 3-Meter Digital Elevation Models for the United States

USGS 3DEP provides a tiled collection of 1/9 arc-second (approximately 3-meter) resolution Digital Elevation Models representing the bare-earth topographic surface. The data serves as the foundational elevation layer for The National Map, supporting earth science studies and mapping applications across the conterminous United States, portions of Alaska, and Guam.

Use Cases

• Perform hydrologic modeling using the 3-meter resolution bare-earth elevation values for watershed delineation.
• Conduct resource monitoring and change detection by analyzing elevation layers derived from lidar and Ifsar source data.
• Create mapping and visualization products for the conterminous United States using the hydro-flattened DEM tiles.
• Support earth science studies with elevation data referenced to the NAD83 coordinate system and NAVD88 vertical datum.

Strengths

• High-resolution 1/9 arc-second (approximately 3-meter) grid cell size.
• Data is processed to a common coordinate system (NAD 83) and vertical unit (meters, NAVD88).
• Derived from diverse source data including high-resolution lidar and interferometric synthetic aperture radar (Ifsar).

Limitations

• Coverage is not nationwide; it is project-based for the conterminous U.S., limited areas of Alaska, and Guam.
• The seamless 1/9 arc-second DEM layer has not been updated since 2015, potentially missing recent terrain changes.
• Data is distributed in pre-staged 15-minute tiled blocks, which may require mosaicking for large-area analysis.

Provenance

Source

U.S. Geological Survey's 3D Elevation Program (3DEP).

Collection Method

Processed from diverse source data (e.g., lidar, Ifsar) to a common specification.

Time Range

null

Freshness

The seamless 1/9 arc-second layer is no longer updated as of 2015, though the collection metadata was last updated in 2026.

Geography

Project-based coverage for the conterminous United States, limited areas of Alaska, and Guam.