Training in Use of the National Hydrography Dataset (NHD) and NHDPlus -
Key National GIS Databases on U.S. Waters
Mapped information on rivers, lakes and streams (hydrography) is a must for any watershed management activity. In the current digital age, Geographic Information Systems (GIS) data on rivers and streams is just as essential. More than just a map, a GIS dataset allows volumes of additional information about streams and rivers to be linked to specific river and stream locations. The result is a powerful ability to analyze, display, and manage watershed/water body relationships and possible impacts rapidly and accurately.
Transforming large-scale maps of millions of stream and river miles into a consistent national dataset, the NHD, was an enormous task that after many years was completed on 2000. The US EPA and the US Geological Survey were the two primary agencies leading this effort, integrating EPA's Reach File Version 3.0 (RF3) and the USGS' Digital Line Graph hydrography data (DLG) to create the initial NHD (1:100,000-scale). Since that time, efforts led by the USGS, USFS and state cooperators have focused on the development of a high resolution version of the NHD (1:24,000-scale or better). These agencies are increasing NHD publicity, outreach and training to stimulate widespread use. This Watershed Academy Stepping Stone links to the following web-based training documents on using the NHD, designed for users with at least an intermediate level of skill in using PC-based mapping and GIS:
In addition, the USEPA and USGS have further collaborated to extend the functionality of the NHD by producing a suite of geospatial products known as NHDPlus. NHDPlus is an integrated suite of application-ready geospatial data sets that incorporate many of the best features of the National Hydrography Dataset (NHD), the National Elevation Dataset (NED), the National Land Cover Dataset (NLDC), and the Watershed Boundary Dataset (WBD). This Watershed Academy Stepping Stone links to the following web-based training exercises on using NHDPlus, designed for users with at least an intermediate level of skill in using PC-based mapping and GIS:
Exercise 4: Navigating with the VAAs and Flow Table (611K, 4 pages, about PDF)