The HUC-12 Watershed Map turns a state abbreviation into a fast, interactive map of every USGS HUC-12 subwatershed in that state — plus publication-quality static output and data in every common format (GeoJSON, GeoPackage, GeoParquet, CSV, PMTiles).
Data comes straight from the USGS Watershed Boundary Dataset. The pipeline handles pagination, geometry cleanup, HUC-4/HUC-8 hierarchy enrichment, and vector-tile generation, so the web map loads in a few hundred KB instead of the ~100 MB the raw state file would otherwise cost.
Click any basin (or the legend) to pin it; the popup then offers a basin-scoped download. Full-state bundles live in the corner panel.
Built by Small Batch Maps — independent cartography focused on clarity and craft.