The goal was to provide access to convenient and intervisible reference points for use by all surveyors participating in the redevelopment over an extended period of time. However, the basic approach to determining elevation has remained almost unchanged throughout that history. The Survey establishes a common basis for use in all phases of the waterfront redevelopment. The vertical datum used to determine elevations has been revised several times throughout the history of the National Geodetic Survey (NGS), as knowledge of our Earth and science expanded. The Survey was conducted in and around the New Whatcom Waterfront Redevelopment site using the NAD83/98 Horizontal Datum and the NAVD88 Vertical Datum.
In 2008, the Waterfront Control Record of Survey (420K PDF) was completed. Survey Control Network for Waterfront Redevelopment Site The map also shows location and ID numbers of the other existing bench marks and monuments that were surveyed for the project. Additional areas of the network are being developed as funding becomes available or as capital projects are surveyed.Īs a result of the efforts mentioned above, Surveying Services has created the Vertical Datum Modernization Project Map (3.8MB PDF). Starting in 2008, the City began working to establish a vertical control network of existing and new bench marks through out the City. Modernization of Vertical Datum to NAVD88 NAVD88 is the vertical datum that is currently employed by most local and federal agencies and therefore on joint agency projects conversions are not necessary, resulting in a more seamless project. In 2008, the City started the process of moving to the new vertical datum with a survey that established hundreds of control benchmarks in NAVD88. The goal is to develop a VDatum utility throughout the country that will foster more effective sharing of elevation data and, eventually, to link such data through national databases.The current vertical datum in use by the City is NAVD88 (North American Vertical Datum of 1988). In addition, the current models are being revisited to include additional foundational geodetic and tidal data acquired that will assist in improving transformational components of the VDatum models, assist in refining and validating the uncertainty associated with models, and to support a wider range of applications. A Southeast Alaska regional model was added in 2019, and future development of coverage for Hawaii, Alaska, and the Pacific territories will commence once foundational geodetic and tidal data are established to allow for valid model construction. The city of Port Townsend horizontal datum is hereby identified as the North. (including the Great Lakes), Puerto Rico, and the U.S. 1.08.020 Plans to conform to adopted horizontal and vertical datums and. VDatum coverage is complete in all coastal regions of the continental U.S. VDatum's capabilities to transform and fuse diverse elevation data benefits coastal applications including inundation modeling (e.g., storm surge, tsunami, sea level rise impacts), ecosystem management and coastal planning, hydrographic surveying using Kinematic GPS for vertical referencing, and shoreline delineation from lidar data.
In a coastal area, for example, a shift in elevation on a gently sloping beach may change the overall depiction of the shoreline or results of inundation mapping. In geodesy, surveying, hydrography and navigation, vertical datum or altimetric datum, is a reference coordinate surface used for vertical positions, such as the elevations of Earth-bound features ( terrain, bathymetry, water level, and built structures) and altitudes of satellite orbits and in aviation.
VERTICAL DATUM FREE
Free to the public, VDatum's primary purpose is to convert elevation data from various sources into a common reference system.Ī common reference system is important because irregularities can occur when maps and charts are created from different data sources.
VERTICAL DATUM SOFTWARE
VDatum stands for Vertical Datum Transformation, an innovative and evolving software tool under development by NOAA's National Ocean Service.
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