GCMRC Survey Department History
In 1990 Glen Canyon Environmental Studies (GCES) began the development of a Geographic Information System (GIS) as a fundamental spatial information archiving and analysis tool. As a result, it became necessary to establish geographic control to produce reliable geo-referenced base maps in areas where scientific research and monitoring data were being collected. The geographic control would spatially reference scientific data in real-world coordinate systems.
In 1990, the Bureau of Reclamation (BOR) remote sensing division contracted the production of topographic base maps for use in selected reaches of the Colorado River using orthorectified aerial photography. The ground control and the coordinate values for control points used to geo-reference the topographic map products were established using GPS technology. Additional ground control points were also traversed and paneled.
In 1991 Joseph Mihalko (NPS surveyor) occupied some of the ground control points for a soil mapping project by the USGS. He found that the control points did not meet their claimed accuracy and precision. As a result, GCES established a survey department to correct all previously established survey control and meet future surveying and mapping requirements.
From 1992 to 1997 the GCES survey department continued the development of the survey data to include additional geographic control, topography, and resource mapping as required by research activities funded by the GCES. The objective was to consolidate all research mapping products into one geo-referenced coordinate system. The system chosen was the Arizona State Plane Coordinate (SPC) system, Arizona Central Zone.