The National Hydrography Dataset (NHD) is a comprehensive set of digital spatial data that contains information about surface water features such as lakes, ponds, streams, rivers, springs, and wells.
The Watershed Boundary Dataset (WBD) defines the areal extent of surface water drainage to a point, accounting for all land and surface areas.
The NHD is stored in and distributed as a geodatabase. The NHD geodatabase contains two feature datasets: Hydrography and WBD. The Hydrography Feature Dataset contains the classic NHD features and the WBD Feature Dataset includes the WBD Hydrologic Units. Subbasins along the US/Canadian boundary now include NHD and WBD into Canada at the 8-digit level.
National Stewardship of the NHD & WBD relies heavily on State Stewards. State Stewards are tasked with representing the interests of the state’s hydrography user community and providing the USGS with the most widely-accepted representation of surface water in the given state.
The Idaho NHD & WBD are actively updated through this NHD/WBD Stewardship Program. Through MOU and other agreements with the United States Geological Survey (USGS), IDWR was named the Principal Steward for the NHD & WBD in Idaho. IDWR accepts input from other agencies and organizations, considers any changes to the NHD/WBD, and updates the NHD/WBD if appropriate. The Principal Steward adjudicates any decision through the Hydrography Technical Working Group (TWG), if necessary.
The following documents are reference documents used by Idaho Sub-Stewards editing the NHD: