Enhancements to the National Hydrography Dataset
The National Hydrography Dataset (NHD) is the surface water component of the U.S. Geological Survey's The National Map. NHD is a detailed hydrographic network containing point data (springs, rapids), linear features (streams, canals) and polygons (lakes, reservoirs). Recent enhancements to NHD have improved the data for AZ. First, NHDPlus High Resolution (NHDPlus HR) adds detailed catchments for every stream segment and many value added attributes to enhance network navigation and analysis (such as flow volumes). Stream classifications have been revised to identify more ephemeral streams. The NHD content has been updated within National Forests and for other regions in AZ. Finally, the new Markup Tool allows NHD users to submit suggested NHD edits to USGS for review and inclusion in the national database. This presentation provides a review of NHD and details on these recent enhancements for NHD, all of which are available to users now.