NHD Geodatabase Review

The National Hydrography Dataset (NHD) has undergone a change. The NHD has a NEW core data model and systems for data management, data maintenance, and data access. The NHDinARC data model and associated systems will continue to receive support while the NHD programs and user community transition to the new design.

A primary reason for this change is to take advantage of new capabilities in ArcGIS with the geodatabase model. The geodatabase model supports a feature-based design that has always been essential to the NHD, data validation behaviors that are critical to maintaining consistency and data integrity, and flow navigation, another critical requirement for the NHD. Another consideration for the move to geodatabase is the availability of Arc Hydro, a data model and applications that are compatible with the NHD.

In addition to the model changes, several other changes are taking place in the NHD system. A new toolset will be available for data maintenance in geodatabase using ArcGIS. The existing data management system has been replaced by a system built around ArcGIS and ArcSDE. Finally, the data access system has a new ArcIMS interface that supports viewing multiple reference layers, direct access to feature information, and provides data extracts by user-defined areas of interest.

This page includes a brief summary of the data model and data content changes, a document listing the FCode changes from NHDinARC to NHDinGEO, and the NHDinGEO data model schema. As additional documentation and links become available they will be added to the page. Please check back periodically for updates.

If you have questions concerning the geodatabase model contact nhd@usgs.gov and include the word "geodatabase" in the subject line.

• Summary of changes for NHDinGEO data
  
  
• Go to the NHD Viewer
  
  
• Software environment: ArcGIS 8.3
  
  
• FCode changes from NHDinARC to NHDinGEO (327 kB pdf file)
  
  
• NHDinGEO data model schema
  • Adobe PDF Format (5.7 MB pdf file)

Some of the documents found on this page are presented in Portable Document Format (PDF); the latest version of Adobe Acrobat Reader or similar software is required to view it. Download the latest version of Acrobat Reader, free of charge or go to access.adobe.com for free tools that allow visually impaired users to read PDF files.