NAD83 SECONDARY INTEGRATION

The Canadian geodetic network that was adjusted with networks of other North American countries, in the July 1986 Continental Adjustment, included only the 8000-station national primary framework. There still remains many thousands of stations contained in regional and local secondary networks to integrate into the North American Datum of 1983 (NAD83). Secondary Integration is a cooperative project organized by member agencies of the Canadian Control Survey Committee (CCSC) which first met in 1982. Since then, members have automated and evaluated secondary network data for approximately 100 000 stations established by conventional, inertial and satellite surveying methods. The task of compiling and testing Helmert blocks for input to the simultaneous adjustment of primary and secondary networks is now underway. This paper describes the plans and progress, and some of the problems that challenge us in the NAD83 Secondary Integration Project.