The Grand Canyon’s Kaibab Trail Suspension Bridge has been recognized as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers (ASCE).
Built in 1928, the Kaibab is a single span suspension bridge connecting the north and south ridges of the Grand Canyon. It’s suspended from four 550-foot-long suspension cables and stabilized by two wind cables. The enormous cables presented a challenge when the bridge was built because motor traffic couldn’t access the remote site location. Instead, the 122 tons of material that were needed to build the bridge were carried on foot and by mule, each suspension cable carried by a line of workers.
Since 1928, the bridge has not been modified, and still carries about 100,000 visitors by foot or by mule every year. The difficult terrain means it’s the only connection between the two sides for 340 miles—between the Navajo Bridge and the Hoover Dam.
“The Kaibab Trail Suspension Bridge is exemplary of the park’s history and reminds us of the challenges that were required to build the bridge across the Colorado River in such an isolated location, without the benefit of modern transportation methods or technologies that we have today,” said Christine Lehnertz, Superintendent of the Grand Canyon National Park, in the ASCE’s press release. “I am proud to see this bridge recognized today as a National Historic Civil Engineering Landmark.”
Today, the National Historic Civil Engineering Landmark designation has been given to over 200 structures across the world. According to the ASCE, it’s given out to “historically significant local, national, and international civil engineering projects, structures, and sites” for creativity, innovation, and work under challenging conditions. Despite the “National” in its name, the award recognizes landmarks across the world. The newest is the Snowy Mountains Hydro-Electric Scheme, an Australian hydroelectric project that redirected the flow of the Snowy River for hydroelectricity and irrigation (completed in 1972).
To the ASCE, the awards are important because they serve as a reminder of the importance of civil engineering—to both members of the general public and civil engineers. “As civil engineers, we take great pride in designing and constructing structures and sites that become legacies of our communities,” said Robin A. Kemper, President of the ASCE. “The Kaibab Trail Suspension Bridge is a prime example of engineering innovation. Engineering this bridge at the base of one of the world’s greatest wonders—the Grand Canyon—illustrates the resourcefulness and innovative spirit of the civil engineers responsible for this project.”
To learn more about the landmarks recognized by the ASCE, visit their website.