NGP Standards and Specifications

Hydrography Standards and Specifications

The National Map serves surface water hydrography data for the United States in several different datasets, including the National Hydrography Dataset (NHD) High Resolution, the Watershed Boundary Dataset (WBD), and the NHDPlus High Resolution (NHDPlus HR).  

Links to specifications tools and information can be found on this page. 

BETA - Spec-X

BETA - Spec-X

Spec-X is a guide for exploring The National Map Specifications. *BETA Release*

Spec-X BETA

NHD User Guide and Feature Catalog

NHD User Guide and Feature Catalog

The NHD User Guide contains Interactive tutorials, a feature catalog, and the NHD Video Library, which can be accessed by clicking on the "NHD User Guide" folder on the left side of the page.

NHD User Guide