Note: the GRS-80 ellipsoid should be used with the NAD-83 datum.Īs of the date of this updated standard, the model to transform between ellipsoid coordinates and NAVD88 heights is GEOID 12B. This datum has several adjustments or realizations over the years, so data custodians should document which they are using. The intent is not to require data providers to convert old data to new coordinate systems, but rather to make clear a preferred set of standards which make sense and provide maximum utility for new technologies. Accurate documentation will be especially important during the transition to a new horizontal datum and vertical datum scheduled for 2022. Specifically, the intent is to minimize the number of datum and map projection/coordinate systems combinations in use and to encourage accurate documentation of the systems referenced by data coordinates. The intent of this standard is to minimize the effort required to use data collected from various sources in New York State. This is not intended to advise the practice of land surveying. The intended audience for this standard is the GIS practitioner community of New York throughout all sectors.

The following recommendations were compiled by the Standards Work Group (now the Standards and Data Coordination Work Group), and have been approved by the Coordinating Body (now the Geospatial Advisory Council).

Standard datum plane