Watershed Boundary Dataset (WBD)
공공데이터포털
The Watershed Boundary Dataset (WBD) from The National Map (TNM) defines the perimeter of drainage areas formed by the terrain and other landscape characteristics. The drainage areas are nested within each other so that a large drainage area, such as the Sacramento River, will be composed of multiple smaller drainage areas, such as the Feather River. Each of these smaller areas can further be subdivided into smaller and smaller drainage areas. The WBD uses six different levels in this hierarchy, with the smallest averaging about 30,000 acres. The WBD is made up of polygons nested into six levels of data respectively defined by Regions, Subregions, Basins, Subbasins, Watersheds, and Subwatersheds. For additional information on the WBD, go to https://www.usgs.gov/core-science-systems/ngp/national-hydrography/watershed-boundary-dataset. DWR is the steward for NHD and WBD in California. We work with other organizations to edit and improve NHD and WBD, using the business rules for California. California's WBD improvements are sent to USGS for certification and incorporation to the national geodatabase. The certified WBD is included within the National Hydrography Dataset downloadable file geodatabase, and is also available in shapefile format and as web map services accessible from the USGS website. (https://www.usgs.gov/core-science-systems/ngp/national-hydrography/access-national-hydrography-products)