National Hydrologic Geospatial Fabric Reference and Derived Hydrofabrics

The four representations are described as the following:

• Reference Hydrofabric, which contains publicly available hydrologic locations and POIs, mainstem rivers, streams, catchments, and waterbodies with linked persistent identifiers, as well as topological, physical, and geometric feature attributes.

• Refactored Hydrofabric where very small catchments have been consolidated into larger ones and very large catchments are split into smaller ones to limit the size and represent important hydrologic locations more precisely.
• Uniform Catchment Size Hydrofabric, a derived hydrofabric where the refactored hydrofabric (described above in #2)  have been aggregated or split to achieve a as close to a user-specified catchment size as possible.
• Point of Interest(POI) Aggregated Hydrofabric, a derived hydrofabric where the refactored hydrofabric (described above in #2) has been aggregated based on around a set of hydrologic locations or POIs.