This site is the centralized location for updates, timelines and useful information on the South Florida Water Management District Vertical Datum Upgrade Project or VDUP. The Vertical Datum Project is the name of the project that is managing SFWMD's transition from NGVD29 to NAVD88
The project goals and objectives are to plan, coordinate and implement a migration of the District's vertical data from the current National Geodetic Vertical Datum of 1929 (NGVD 29) and other datums, to the North American Vertical Datum of 1988 (NAVD 88) through a controlled, well-communicated, technically sound, and properly managed process. The new data framework will meet the District's needs and as much as possible also be compatible with federal, state and local governmental agencies. Successful completion of the VDUP will result in all District functions consistently and universally employing NAVD 88 as their primary vertical datum.
NAVD88 is an immense improvement over its predecessor in terms of mathematical techniques employed as well as being based on the Earth's observed gravity field. NAVD88 is compatible in principle with the Geoid, the mathematical system of describing the relation of the Earth's gravity field to elevations and was a minimally constrained adjustment, constrained only to the primary tidal benchmark at Father Point Rimouski, Quebec, Canada. Approximately 100,000 miles of leveling had been added to the National Geodetic Reference System (NGRS) since NGVD 29 was created. In the early 1970s, NGS conducted an extensive inventory of the vertical control network. Many existing benchmarks were affected by crustal motion associated with earthquake activity, postglacial rebound (uplift), and subsidence. Other problems (distortions in the network) were caused by forcing the 100,000 miles of leveling to fit previously determined NGVD 29 height values. NAVD88 was created to eliminate those errors, incorporate the additional leveling, and to produce a new network that is consistent with both conventional and GPS leveling.
Instead of relying on "mean sea level" to determine the elevation of a point, the District will utilize the sophisticated elevation reference system for the North American continent. Eventually, all countries in North America will use this same network of vertical reference points to support many diversified uses
Impacts on Florida
