Cloud-native mirror of the USGS Watershed Boundary Dataset: a seamless, nested hierarchy of hydrologic units for the United States and territories, from HUC2 regions down to HUC12 subwatersheds.
WBD_National_GDB.zip, updated 2025-01-07). Public domain (US Government work).s3://public-usgs-wbd/ · public URL base https://s3-west.nrp-nautilus.io/public-usgs-wbd/HUC codes nest: a HUC12 code contains its parents as prefixes — 180701050402 →
HUC2 18, HUC4 1807, HUC6 180701, HUC8 18070105, HUC10 1807010504. So the single HUC12 hex
layer answers "what watershed is this point in?" at every level.
Never
SUMper-feature columns on the hex layer.areasqkm,areaacres,shape_Area,shape_Length, and the non-contributing-area columns are the subwatershed's totals, repeated on every hex row it covers. For area, useCOUNT(DISTINCT h8) × cell_area_at_resolution_8, orSELECT DISTINCT huc12, areasqkmbefore aggregating. The H3 index columns (h8,h0) are safe to aggregate.
The PMTiles source-layer is the level id (hu2 … hu12), not the GDB layer name.
Every level carries huc{N}, name, areasqkm/areaacres, states (comma-separated postal codes),
and source-provenance fields (tnmid, loaddate, globalid, …). Local levels add:
hutype (S=Standard, C=Closed Basin, F=Frontal, M=Multiple Outlet, W=Water, I=Island,
U=Urban, D=Indeterminate) and humod (modification codes; NM=No Modification).tohuc (downstream HUC12 for surface-flow routing) and non-contributing-area columns.See each level's stac-collection.json for full per-column documentation.
Converted from the USGS national WBD GDB with cng-datasets
(DuckDB-native GeoParquet, tippecanoe PMTiles, H3 polyfill for hex). Source CRS EPSG:5498
(NAD83 + NAVD88 height) reprojected to OGC:CRS84. Public domain — free to use, share, and adapt.
| HUC12 | Subwatershed | huc12 | 103,068 | ✅ | ✅ | ✅ (res 8) |