WELCOME to the Horizon Systems' NHDPlus Website

NHDPlus is a geo-spatial, hydrologic framework dataset built by the US EPA Office of Water, assisted by the US Geological Survey. Since its first release in 2006, NHDPlus has been made available to the wider water resources community and has been used for many diverse applications by Federal, state, and local governments, as well as non-profit oganizations, private companies and educational institutions. The NHDPlus user community has developed tools and ancilliary data to support their NHDPlus applications. Some of these applications are listed here.

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), and the Watershed Boundary Dataset (WBD). NHDPlus Version 1 (NHDPlusV1) was released in 2006. NHDPlus Version 2 (NHDPlusV2) began its public debut in June 2012. Both NHDPlusV1 and V2 incorporate the NHD 1:100,000-scale stream network and the 1 arc-second NED (approximately 30 meter ground spacing).

Both versions of NHDPlus are available from the links on the left-hand side of this page. NHDPlusV2 is the most recent and comprehensive version of NHDPlus and replaces NHDPlusV1. New and existing NHDPlus users are strongly encouraged to use the vastly improved NHDPlusV2.

Like NHDPlusV1, NHDPlusV2 data is distributed by drainage area. NHDPlusV2 divides the continental U.S. into 26 drainage areas, all of which are available for download. NHDPlusV2 is available for the continental United States, Hawaii, Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Marianas.

NHDPlusV2 is different from NHDPlusV1 in a number of significant ways. You are encouraged to read the NHDPlusV2 User Guide which contains sections that compare and contrast the two versions. For users of NHDPlusV1 who wish to migrate to NHDPlusV2, a feature crosswalk from stream lines in NHDPlusV1 to streamlines in NHDPlusV2 is available (see NHDPlusV1-to-V2 Crosswalk)

Since 2003, Horizon Systems has played a pivotal role in the development of NHDPlus, providing leadership, software development and user support as a contractor to US EPA and USGS. This website is sponsored by Horizon without federal funding and provides access to NHDPlus data, tools, documentation, and services. In addition to providing NHDPlus application development support to the water resources community, Horizon is currently working with the USGS to develop High Resolution NHDPlus (NHDPlus HR) from the High Resolution NHD (1:24,000-scale or better) and the 1/3th arc-second NED (approximately 10 meter ground spacing). News about this project is available at NHDPlus HR.

The NHDPlus Team at Horizon Systems can be reached at [email protected].

Thank you for your continued interest in, and use of, NHDPlus!

News & Updates

If you would like to receive occasional emails about the availability of NHDPlus data, tools and updates, send your name, phone number, organization, and email address to [email protected].

All NHDPlus Support is available through email to [email protected].