Version 1.06

A new version of the VDatum software is presently being transitioned for release on this webpage. Three new VDatum applications will be released with this software for the following areas:

* Chesapeake and Delaware Bays
* Mobile Bay to Cape San Blas, FL
* New Jersey to Narragansett Bay, including Long Island Sound

Please contact Dr. Edward Myers to arrange for a CD to be made and sent to you. Existing VDatum applications have been modified to work with the new software, and specific download instructions will be made available on this website.

VDatum transformation software is accessible by clicking on the geographic names on the image map of the continental U.S.

Projects

VDatum was initially developed for the Tampa Bay Demonstration Project, conducted by NOAA and the U.S. Geological Survey. For this pilot project, VDatum was applied to transform coastal elevations to a common vertical datum to integrate bathymetry and land topography into a digital elevation model useful for coastal managers and decision makers (MiIlbert and Hess, 2001; Parker, 2002). Subsequent VDatum software development for other coastal regions marks the steady expansion toward national VDatum coverage (Hess et al. 2005; Myers, 2005 (7 pages, pdf); Myers et al. 2005).

In addition to those completed above, VDatum projects are well underway for Southern California, the Pensacola Bay, the Chesapeake Bay, the Delaware Bay, New Jersey - New York Harbor - Long Island Sound to the Narragansett Bay, and the Gulf of Maine.  As regional projects begin to overlap, a seamless National VDatum will emerge to cover all of the U.S. coastal areas, from estuaries out to 25 nautical miles (463 km) from land.

Disclaimer: Although many of the vertical datum transformations between the North American Vertical Datum of 1988 (NAVD 88) and mean sea level, and between mean sea level and the other tidal datums, are based on tidal values from the present National Tidal Datum Epoch (NTDE, 1983 to 2001), some are based on data from older tidal epochs. NOS is in the process of updating the data in VDatum to conform to the latest NTDE. In the meantime, care should be used when applying these transformations.