Common use of Datums Clause in Contracts

Datums. A datum is a geometrical quantity (or set of quantities) that serves as a reference, forming the basis for computation of horizontal and vertical control surveys in which the curvature of the earth is considered. Adjusted positions of the datum, described in terms of latitude and longitude, may be transformed into State Plane Coordinates. All engineering work (mapping, planning, design, right of way, and construction) for WSDOT projects is based on a common datum.