Per-project ("classic") 1-meter Digital Elevation Models from the USGS 3D Elevation Program (3DEP), staged on The National Map's public S3 bucket.

Source & method: Bare-earth DTMs derived from 3DEP-quality airborne lidar, published per acquisition project as delivered. Unlike the reprocessed seamless S1M product, tiles keep each project's original processing: adjacent projects may show seams, and overlapping projects of different vintages both remain available.

Resolution: 1 m ground sample distance, 10 km x 10 km tiles.

Coordinate reference: NAD83 UTM zones (per-tile, see each item's assets); elevations in meters on NAVD88 (EPSG:5703).

Coverage: Most of the conterminous US plus parts of Alaska and Hawaii, growing as 3DEP projects publish. Acquisition dates span roughly 2010 to present and vary per project — see each item's start/end datetimes.

Documentation:

Access

The catalog is browsable without a key. Elevation lookups need a free API key, sent as an X-API-Key header; see the quickstart.

curl "https://api.darly.io/collections/usa-usgs-3dep-1m/items?limit=5"

curl -H "X-API-Key: $DARLY_API_KEY" \
  "https://api.darly.io/v1/elevation/point?lat=33.54&lon=-112.18&collections=usa-usgs-3dep-1m"

from pystac_client import Client

catalog = Client.open("https://api.darly.io")
search = catalog.search(collections=["usa-usgs-3dep-1m"], bbox=[-159.79, 17.67, -64.56, 49.4], max_items=5)
for item in search.items():
    print(item.id, item.assets["dtm"].href if "dtm" in item.assets else item.assets["dsm"].href)

Providers

U.S. Geological Survey, 3D Elevation Program (3DEP) — producer, licensor, host
Darly — processor

Citation

U.S. Geological Survey, 2019, USGS one meter digital elevation model: U.S. Geological Survey data release, https://doi.org/10.5066/P9GAJ9AZ.