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National Hydrography

The National Hydrography Dataset (NHD) and Watershed Boundary Dataset (WBD) are digital geospatial datasets that map the surface water of the United States.

The National Hydrography Dataset (NHD) and Watershed Boundary Dataset (WBD) are digital geospatial datasets that map the surface water of the United States and are a part of The National Map. The NHD represents the nation’s drainage networks and related features, including rivers, streams, canals, lakes, ponds, glaciers, coastlines, dams, and streamgages. The NHD High Resolution, at 1:24,000 scale or better, is the most up-to-date and detailed hydrography dataset for the nation (please visit the NHD Medium Resolution page for information about accessing the legacy 1:100,000 scale dataset). The WBD represents drainage areas of the country in eight nested levels.

Together, the NHD and WBD, along with data from the 3D Elevation Program (3DEP), are processed to create the NHDPlus High Resolution (NHDPlus HR), a networked geospatial framework of stream reaches, elevation-based catchment areas, flow surfaces, and value-added attributes that enhance stream network navigation, analysis, and data display. The NHDPlus HR brings modeling and assessment down to a local, neighborhood level, while nesting seamlessly into the national context.

The NHDPlus HR framework extends the hydrologic network seamlessly across the terrain by including not only streams, but also associated catchment areas that drain to each stream segment. This association allows information about the landscape to be related to the stream network. Using tools such as the Hydrography Event Management (HEM) tool, observational data on the stream network, such as fish populations, invasive species, stream discharge, and water quality, can also be linked to the framework. Using the framework, linked information, and other hydrologic and topographic characteristics, it is possible to study relationships, such as how a toxic spill upstream might affect a fish population or drinking water downstream.

The NHD and WBD are managed by the USGS under OMB Circular A-16 and as a part of the FGDC NGDA Inland Water Theme, with collaboration, support, and cost-sharing with many other federal, state, and local entities. This includes formalized Stewardship Agreements with partners to improve the NHD and WBD locally. Many tools exist to help with editing of the data, and many user resources are available.

Direct download links and web-based map service information are available from the Links to Data Products and Map Services page. Downloads via interactive map are available from The National Map Download viewer, and all web-based map services are listed at The National Map Service Endpoints page.

Join our community! We communicate monthly through the NHD Newsletters and NHD/WBD Advisory Calls, and hold special seminars and workshops as well. Please visit the News and Events tab on the left for more information.