The Last Major High Accuracy Classical Geodetic Survey Operation Undertaken in Canada: The 1983 Rogers Pass Survey for a 14.5 km Railway Tunnel

Gérard Lachapelle

Abstract:	The survey specifications required for a 14.5 railway tunnel excavated in Glacier National Park, B.C., in the early 80s are described, together with the geodetic challenges posed by the surrounding mountains. In that pre-GPS area, the establishment of a high accuracy surface geodetic network to subsequently provide the survey alignment of the excavation equipment at both ends of the tunnel became a major undertaking, requiring a detailed knowledge of geodesy. Major parameters included the design of the network, the design and installation of survey tripods, the selection of high performance range and angle measurement equipment, and the selection and execution of first-order geodetic astronomical observations to provide an absolute and accurate orientation of the network. Illustrations show the geodetic station selection process, the equipment selected and the execution of the operations. An important challenge in such a mountainous region was the effect of the rugged gravity field on the geodetic observations and the use of proper procedures to deal with these effects. The post-analysis of the surface network measurements showed how the accuracy specified was met.
Published in:	Proceedings of the IAIN World Congress and the 56th Annual Meeting of The Institute of Navigation (2000) June 26 - 28, 2000 The Catamaran Resort Hotel San Diego, CA
Pages:	520 - 562
Cite this article:	Lachapelle, Gérard, "The Last Major High Accuracy Classical Geodetic Survey Operation Undertaken in Canada: The 1983 Rogers Pass Survey for a 14.5 km Railway Tunnel," Proceedings of the IAIN World Congress and the 56th Annual Meeting of The Institute of Navigation (2000), San Diego, CA, June 2000, pp. 520-562.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In