and not easy to walk through. The seabirds often burrowed into the soft peat, and many times the ground collapsed and dropped me into a knee-deep bird burrow.” Even as a self-described “rookie surveyor,” Houston quickly learned to operate the GNSS equipment. With CenterPoint RTX operating trans- parently, he could focus on the engineering aspects of his work. Only on a couple of occasions did he need guidance; he used the island’s satel- lite internet link to discuss technical questions with Trimble experts. At the end of each day, Houston reviewed data on the controller, planned the next day’s work, and set up the system batteries for recharging. Aside from cloth tapes used to lay out a rough grid, the R10 was the only survey tool Houston needed. Although he did not establish any formal benchmarks or control points, Houston did capture several hard points on the existing helipad and building foundations. Those markers will be sufficient to serve as reference points for the upcoming work on the island. A Job Done Well Houston departed Gough Island with survey data sufficient for the de- sign work ahead. Taylor & Boyd developed 2D contour maps and 3D terrain models of the site, which they shared with RSPB. The society will overlay bird data on the topographic maps and use the information to identify flight paths and nesting areas. Taylor & Boyd will use the maps to set proposed elevations and positions for the temporary struc- tures. The data, which is the first topographical survey ever carried out Houston and a colleague share a path with a flock of Southern Rockhopper penguins.
on the base since it was established in 1963, will also aid the South African government in maintenance and operations of island facilities. Houston made it clear that he could not have carried out the survey to the required level of accuracy and within the allocated time period without CenterPoint RTX. “It really was invaluable for the success of the project,” he said. “If this technology works on Gough Island, then it will work anywhere.” Taking a few moments to reflect on his trip, Houston said the time on the island was well worth the long trip and rugged conditions. The opportunity to see and interact with the birds, seals and penguins left a lasting mark. While he doesn’t expect a return trip will be needed, he would jump at the opportunity. “It was a once in a lifetime experience,” he concluded. “I would go back in a heartbeat—with warmer clothes.”
JOHN STENMARK, LS, is a writer and consultant working in the AEC and technical industries. He has more than 20 years of experience in applying advanced technology to surveying and related disciplines.
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february 2020
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