Watershed Assessment, Tracking & Environmental ResultS

Watershed Boundary Dataset

Source: http://www.ncgc.nrcs.usda.gov/products/datasets/watershed/index.html

The newly released Hydrologic Unit Code (HUC) 12-digit Watershed Boundary Dataset (WBD) provides one of the fundamental frameworks upon which analysis and reporting of WATERS programs takes place upon.  Note that the current WBD does not include Alaska.

Layers currently stored in the WATERS instance:

  

• WBD_HUC12
  12-digit subwatershed region polygons as released by Natural Resources Conservation Service. 
    
  
• WBD_HUC10
  10-digit watershed subregion polygons aggregated by Hydrologic Unit Code.
   
  
• WBD_HUC8
  8-digit subbasin polygons aggregated by Hydrologic Unit Code.  Note this layer is the eventual replacement for the old subbasin layer stored in the RAD.
   
  
• WBD_HUC6
  6-digit basin polygons aggregated by Hydrologic Unit Code.  Note this layer is the eventual replacement for the old rad_huc6d layer stored in the RAD.
   
  
• WBD_HUC4
  4-digit subregion polygons aggregated by Hydrologic Unit Code.  Note this layer is the eventual replacement for the old rad_huc4d layer stored in the RAD.
    
  
• WBD_HUC2
  2-digit region polygons aggregated by Hydrologic Unit Code.  Note this layer is the eventual replacement for the old rad_huc2d layer stored in the RAD.
  

Storage Details for WBD Layers

• Metadata for WBD layers is available via the Geospatial One-Stop by clicking on the metadata buttons above.
   
  
• WBD tables are stored in the waters_wbd schema with all tables publically accessible.
    
  
• WBD tables are stored twice, as both Oracle Spatial (suffix _OS) and as ESRI ST_GEOMETRY (suffix _SDE) storage types.
    
  
• WBD tables are stored in the same coordinate space (NAD83) as RAD and NHD layers.
    
  
• WBD tables are registered to ArcSDE allowing use by any ESRI client.
    
  
• WBD tables are named indicating the vintage of the data (i.e. WBD20090316_HUC12_OS).  To account for future updates to the WBD, each table has a spatial view with no vintage information in the name (i.e. WBD_HUC12_OS) which should be used when hard-coding tablenames in services and procedures.  By using the generic view name, the developer can be assured that they will pull the most recent information available in the WATERS instance.
    
  
• All views of the WBD are ArcSDE registered spatial views.