NAVD 88 is the abbreviation for the North American Vertical Datum of 1988. NAVD 88 is one of five current National Geodetic Datums, which are coordinate systems that act as standard reference lines to measure points on the earth’s surface in the region that they apply.
As you may know, base flood elevations, and therefore elevation certificates, used to be based on NAVD29 (which was created in 1929), but are now typically based on NAVD88, which was established in 1988. Though we rarely see it spelled out, NAVD stands for National Geodetic Vertical Datum.
People also ask
What does NAVD stand for in elevation?
What is the elevation of the water in NAVD 88?
What is the NAVD 88 datum based on?
What is the difference between elevation and datum?
The upgrade to NAVD 88 means that the values we associate with the height of water – what many people think of as mean sea level – will change. Within the SFWMD boundaries, measurements of water levels in NAVD 88 will be approximately -0.6 feet to -1.8 feet lower than they are in NGVD 29, as elevation difference varies by geographic location.
Within the boundaries of the District, the NAVD 88 elevation number is a shift of approximately 0.7 to 1.1 feet lower that the elevation in the NGVD 29 standard. This variation is due to geographical differences. For example, a water level for Lake Panasoffkee of 39.24 feet in NGVD 29 will be 38.36 in the NAVD 88 standard.
A vertical position is the height of a point relative to some reference surface, such as mean sea level, a geoid, or an ellipsoid. The roughly 600,000 vertical control points in the U.S. National Spatial Reference System (NSRS) are referenced to the North American Vertical Datum of 1988 (NAVD 88).
The elevation in NAVD 88 would be: 54.2 + -0.609 = 53.591 or 53.6 ft. Remember, if you add a negative number to the existing elevation, the resulting elevation will be a lower number. In the second example, the conversion factor for Arroyo Seco is 2.99.
Mar 19, 2015 · As an example, using the table above, if you have a first floor elevation of 6.0 ft (Richmond Datum) for a property in Staten Island (Richmond County) then the elevation in NAVD88 would be: 6.0 ft + 2.092 feet = 8.092 ft.
Use of the term "sea level" as a synonym for NGVD 29 in USGS publication series information products is discontinued. However, Mean Sea Level (MSL), a tidal datum that pertains to local mean sea level, should not be confused with or substituted for the fixed datums of NGVD 29 or NAVD 88.
The North American Vertical Datum of 1988 (NAVD 88) is the vertical datum for orthometric heights established for vertical control surveying in the United States of America based upon the General Adjustment of the North American Datum of 1988.