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Vertical Datum

The current vertical datum in use by the City is NAVD88 (North American Vertical Datum of 1988). 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. 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.

Modernization of Vertical Datum to NAVD88

Starting in 2008, the City began working to establish a vertical control network of existing and new bench marks through out the City. Additional areas of the network are being developed as funding becomes available or as capital projects are surveyed. The Report of NAVD88 Bench Marks (1.7MB PDF) is a comprehensive list that includes additional bench marks that were added with capital improvement project surveys.

As a result of the efforts mentioned above, Surveying Services has created the Vertical Datum Modernization Project Map (3.8MB PDF), which is interactive and provides links to the individual survey mark reports for new bench marks. The map also shows location and ID numbers of the other existing bench marks and monuments that were surveyed for the project. The complete results for the 2008 project are reported in the NAVD88 Datum Modernization Coordinates Report (1.7MB PDF).

Survey Control Network for Waterfront Redevelopment Site

In 2008, the Waterfront Control Record of Survey (420K PDF) was completed. The Survey was conducted in and around the New Whatcom Waterfront Redevelopment site using the NAD83/98 Horizontal Datum and the NAVD88 Vertical Datum. The Survey establishes a common basis for use in all phases of the waterfront redevelopment. 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. The Survey provides an explanation of the relationship between NAVD88, City of Bellingham, NGVD29 and Tidal MLLW Datums.

Those results are also displayed in the interactive Waterfront Survey Control Network Map (300K PDF), which provides links to the individual Survey Mark Reports.

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