Freezing temperatures and historic snowfall were not enough to dampen the spirts of those in attendance for the dedication ceremony of the Kaibab Trail Suspension Bridge as an ASCE National Historic Civil Engineering Landmark. The ceremony, held on February 23, 2019 at the south rim of the Grand Canyon, included a brief history of the “Black Bridge” by Jonathon
Upchurch, a presentation of the landmark plaque by ASCE President Robin Kemper, an acceptance of the landmark plaque by Grand Canyon Deputy Superintendent Lisa Carrico, and remarks from the presidents of the ASCE Arizona Section and Grand Canyon Historic Society, Ted Smithwick and Dave Mortenson, respectively. Those in attendance included members of ASCE and the Grand Canyon Historic Societies, park staff, students, and park visitors. In advance of the dedication ceremony, two landmark plaques were installed by
National Park Service staff. The first plaque, the most accessible of the two, is installed on the south rim near the Yavapai Geology Museum. The second plaque, which entails a steep hike into the canyon, is installed at the bridge itself, nearly a mile lower in elevation. The Kaibab Trail Suspension Bridge was built in 1928 at the bottom of the Grand Canyon and at the time  provided the only Colorado River crossing between Moab, Utah and Needles, California. Even today, the Black Bridge and its neighboring Silver Bridge (constructed in the 1960s) are the only crossings between the Navajo Bridge and the Hoover Dam (both of which are also dedicated ASCE National Historic Engineering Landmarks). The construction site was so remote that access was limited to humans and mules, descending over 4,780 feet into the canyon by way of the 7-mile South Kaibab Trail. The 440-foot suspension bridge required 122 tons of materials and supplies, including four 550-foot suspension cables, each weighing in at one ton. These cables were carried down the trail by 42 Havasupai tribesmen walking single file. The remaining pieces were hauled down by human power or by mules, with each piece being no longer than 10-feet and weighing no more than 200 pounds. “As civil engineers, we take great pride in designing and constructing structures and sites that become legacies of our communities”, said ASCE President Robin Kemper. “The Kaibab Trail Suspension Bridge is a prime example of engineering innovation. Engineering the bridge under such unfavorable conditions reflects on the resourcefulness and innovation of the civil engineers responsible for this project.” The Arizona Section thanks Jonathon Upchurch, P.E., PTOE, F.ASCE for his work on the nomination application and for organizing the dedication ceremony. To learn more about ASCE’s Historic Civil Engineering Landmark Program, please visit www.asce.org/history
and Arizona’s Historic Landmarks, by visiting www.azsce.org/azsce-news/historyheritage.
The event was covered by several news organizations:
AZ Central: 91-year-old Grand Canyon bridge named an engineering landmark
Grand Canyon News: Kaibab Trail’s Black Bridge named National Historic Civil
Engineering Landmark
Civil + Structural Engineer: Kaibab Trail Suspension Bridge Recognized as National
Historic Civil Engineering Landmark
Engineering.com: Pioneering Grand Canyon Bridge Nabs ASCE Award
The bridge was also covered by the February issue of Arizona Highways Magazine, and will
be featured in next month’s ASCE Civil Engineering Magazine

Newsletter Schedule

• April 2019 – Kaibab Trail Suspension Bridge Dedication Ceremony
• May 2019 – Winning Friends and Influencing People
• June 2019 – An Interview with an Arizona ASCE Member
• July 2019 – How to Save Someone’s Life
• August 2019 – My Thoughts on ASCE
• September 2019 – Thank you
• October 2019 – Breanna Connolly Takes Over the President’s Message