Geodetic control serves as a common reference system for establishing coordinate positions for all geographic data. Traditionally, geodetic control points are established as permanent physical monuments placed in the ground and precisely marked, located, and documented. Specifying locations of features relative to geodetic control makes it possible to assess the locational accuracy of these features. Interest and activity regarding geodetic control has dramatically increased, corresponding to the need for accurate maps and surveys for geographic and land information systems.
The MSDI Plan for geodetic control envisions a state-local collaborative solution. The state assembles an electronic database about geodetic connected monuments and makes it readily available to all users over the Internet. The database features control survey monument data that are readily useable and meet the broad user communityís desired specifications for accuracy. Many organizations contribute information to the geodetic control network. A statewide solution for real time kinematic GPS surveying enables greater efficiencies to the data producing organizations. Funding and other incentives enable state agencies and local units of government to add to the control survey network and encourage participation and publication of their data.
The strategic plan for addressing the state's needs for geodetic control is being developed by a geodetic control data workgroup with assistance from the Strategic Plan Committee of the Governor's Council on Geographic Information.
The Geodetic Control network is a very high priority for professional surveyors, GIS developers and spatial data gatherers in Minnesota. Control surveys establish precise horizontal and vertical positions of geodetic monuments. These serve as the basis for originating or checking subordinate surveys for projects such as topographic and hydrographic mapping, property boundary delineation, route and construction planning, and design and layout. They are also essential as a reference framework for giving locations of data entered in Land Information Systems (LIS) and Geographic Information Systems (GIS).
The MSDI Data Plan for geodetic control (version 1.1) was completed in May 2003 and reformatted in August 2003. A revised plan will be completed by the summer of 2005.
The current state geodetic control network is supported in Mn/DOTís operating budget. Costs to complete densification, expand the GPS referencing system, facilitate data entry, and expand local participation have not been determined.
To learn more about the strategic plan for meeting parcel data needs within Minnesota, contact the workgroup chair.