is a Data Source.
The National Hydrography Dataset (NHD) is the U.S. Geological Survey's authoritative geospatial representation of the surface water features of the United States, including rivers, streams, canals, lakes, ponds, and other waterbodies. The associated NHDPlus products add value with flow direction, network connectivity (NHDFlowline), waterbody features (NHDWaterbody), and catchment attributes. SAWGraph uses NHD and NHDPlus data as a geospatial reference source for modeling surface water features and the flowlines that connect them, supporting spatial context for PFAS observations.
| ID | Name | URL | Category | Format | Description |
|---|---|---|---|---|---|
| usgs-nhd.landing | USGS National Hydrography Dataset landing page | national-hydrography-dataset | GraphicalInterface | http | USGS landing page for the National Hy... |
| usgs-nhd.nhdplus | USGS NHDPlus High Resolution | nhdplus-high-resolution | GraphicalInterface | http | USGS landing page for NHDPlus High Re... |
| ID | Name | URL | Category | Format | Relation | Description |
|---|---|---|---|---|---|---|
| sawgraph.graph | SAWGraph PFAS Knowledge Graph | pfas-kg | GraphProduct | ttl | was influenced by | The SAWGraph PFAS knowledge graph, in... |
| geoconnex.graph | GEOCONNEX Knowledge Graph | geoconnex.us | GraphProduct | ttl | had primary source | The Geoconnex knowledge graph, an ope... |
| hydrologykg.graph | SAWGraph Hydrology Knowledge Graph | water-kg | GraphProduct | ttl | had primary source | The SAWGraph Hydrology knowledge grap... |
| uf-okn.graph | UF-OKN Knowledge Graph | Knowledge-Graph | GraphProduct | ttl | had primary source | The UF-OKN knowledge graph, published... |
The National Hydrography Dataset (NHD) is the U.S. Geological Survey’s authoritative geospatial representation of the surface water features of the United States, including rivers, streams, canals, lakes, ponds, and other waterbodies. The associated NHDPlus products add flow direction, network connectivity (NHDFlowline), waterbody features (NHDWaterbody), and catchment attributes.
SAWGraph uses NHD and NHDPlus as a geospatial reference source for modeling surface water features and the flowlines that connect them, providing spatial context for PFAS observations.
Created: July 01, 2026 | Last modified: July 01, 2026