Elevation-Derived Hydrography Data Acquisition Specifications: Delivered Products and Formats Requirements

Delivered products shall include the following:

• A geopackage containing all NHD features not captured in the elevation-derived hydrography dataset, particularly named features, as along with omitted 3DEP breaklines.
• A spatial metadata containing four layers, in geopackage format:
  • DPA: The original DPA provided to the data producers as the area to be delineated with elevation-derived hydrography.
  • FDPA: The extent of data being submitted as a deliverable. Shall be submitted as a single polygon, or multipart polygon only in cases where work unit areas are discontinuous such as islands or noncontiguous hydrologic units.
  • Elevation Project Polygons: 3DEP WESM polygons representing the 3DEP DEMs used for elevation-derived hydrography, or polygon extents for sources other than 3DEP.
  • DEM_Limitation: Boundaries of areas where there are limitations such that the DEM is unsuitable for deriving hydrographic data.
• An elevation-derived hydrography dataset shall be delivered in a current version of the file geodatabase template provided by the USGS.
• A seamless DEM from which the hydrography was derived, in GeoTIFF or GeoTIFF (COG) format.
• If available, 3DEP hydroflattening breaklines for the source elevation datasets shall be provided with the elevation-derived hydrography delivery as one polygon dataset in a geopackage.
• An XML metadata file for the elevation-derived hydrography file geodatabase, in FGDC format.
• A collection report summarizing the product, processing steps, project area, and any unusual conditions for the project area.
• A summary of any accuracy assessments completed on the data. This may be a section within the collection report.