Data and Documentation
MSDI Hydrography Data
The Montana State Library updates and maintains the National Hydrography Dataset in partnership with the USGS. MSL offers the high resolution (1:24K) NHD in geodatabase and shapefile formats (refreshed twice a year) projected to the Montana State Plane Coordinate System.
NHD Database Documentation
For more information on the structure of the NHD Geodatabase, see the NHD User Guide and the database schema version 2.1 (pdf file). Additional documentation and tutorials can be found at the USGS NHD Website.
The National Map NHD viewer
The National Map online mapping application is maintained by the USGS. It provides a viewer and download platform to visualize, identify, and download the National Hydrography Dataset, as well as other spatial data, such as elevation, land cover, and structures.
Hydrography includes surface water features such as lakes, ponds, streams and rivers, canals, oceans, and coastlines. Hydrography is important to many applications. As with other data themes, many users need hydrographic features as reference or base map data. Other applications, particularly environmentally oriented analyses, need the information for analysis and modeling of water supply, pollution, flood hazard, wildlife, development, and land suitability.