Balanced perspective
Inspectors use rope access to examine hard-to-reach areas under New Mexico bridge
By Eric Widholm
Inspecting the structural integrity of the Rio Grande Gorge Bridge in northern New Mexico takes significant skill, but it also requires considerable courage.
Just gazing over the edge of the seventh highest bridge in the United States and 82nd highest bridge in the world – 565 feet above the Rio Grande at its highest point – leaves most people weak in the knees. The bridge offers stunning views as the river carves through the flat, tan desert landscape framed by the Sangre de Cristo Mountains.
So it’ s understandable when even brave structural inspectors must suck in a deep, thin-aired breath before carefully taking their first step over the railing using rope access equipment to examine the bottom chord – the lowest longitudinal member of this truss bridge.
“ It’ s very exciting, and your stomach is in knots, just given the height,” said Brian Schroeder, Ayres Associates’ project manager and lead inspector.
The thrill subsides quickly, however, and it’ s time to get to work. The massive structure – part of US Highway 64, a major east-west route in New Mexico – becomes the office for two days. Inspectors get up-close-and-personal with half of the bridge each day, taking photos and documenting conditions to ensure the structure remains safe for the public.
“ Within the first few minutes, once you get down on the bridge and start working, you’ re more focused on the bridge itself than your surroundings,” Schroeder said.“ It doesn’ t take long to adjust. The people we’ re working with are used to working at heights.”
This team of inspectors is led by New Mexico State University’ s bridge inspection program, which has been providing the biennial inspections of the Gorge Bridge for decades. The last two cycles – in 2013 and this September – required arms-length, in-depth inspections of the bottom chord and connecting diagonal members.
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