Kootenai River Study
Vertical Datum Conversions
The conversion program VERTCON computes modeled differences in orthometric height between the North American Vertical Datum of 1988 (NAVD 88) and the National Geodetic Vertical Datum of 1929 (NGVD 29) for a given location specified by latitude and longitude. About 382,000 points throughout the United States were used to compute corrections to the model. The root-mean-squared error was computed to be less than 0.07 ft. The VERTCON program was developed by the National Geodetic Survey (NGS) and the National Oceanic and Atmospheric Administration (NOAA).
Go To VERTCON Conversion Program
Selected Height Conversions for the Study Area from NGVD 29 to NAVD 88
- Porthill, ID = 4.035 ft.
- Copeland, ID = 3.950 ft.
- Klockmann Ranch, ID = 3.901 ft.
- Bonners Ferry, ID = 3.858 ft.
- Moyie Springs, ID = 3.940 ft.
- ID/Montana State Line = 3.865 ft.
- Troy, MT = 3.835 ft.
- Footbridge at Kootenai Falls, MT = 3.885 ft.
- Libby, MT = 3.848 ft.
- Libby Dam, MT = 3.852 ft.