The recent collapse of Double Arch, a stunning geological formation in Utah, shocked visitors and marked the loss of a cherished natural wonder. However, experts believe this event was unavoidable.

This magnificent structure, located in Glen Canyon National Recreation Area in southern Utah, fell last Thursday, as confirmed by the National Park Service the following day.

“It’s part of the natural lifecycle of an arch,” explained Jeff Moore, a geology professor at the University of Utah, who has been studying several arches in Arches National Park since 2013.

The park service noted that the arch had been eroded over its approximately 190 million-year existence. Fluctuations in water levels and variations in wind and weather conditions might have also played a role in its collapse.

Erosion of arches is a natural process

According to Grant Willis, a retired geologic mapping program manager at the Utah Geological Survey, Double Arch exhibited signs of aging before its collapse.

“Every arch undergoes a lifecycle,” he stated. “This doesn’t relate to years but to the arch’s physical development.”

“There’s no doubt Double Arch was on the older side,” he mentioned.

Moore described the arch as a “natural sculptural creation” shaped by erosion.

“These structures develop through gradual erosion, forming and enlarging over time. In some cases, they can evolve into strong arches; in others, they may not,” he noted.

The strength of an arch often depends on its lintel, or its supportive feature, and the amount of unsupported rock it possesses.

“The arches that luck into developing strong lintels tend to last longer, while those with weaker structures, like Double Arch’s flatter lintel, do not fare as well,” he explained.

Could human activity have contributed to the collapse?

Moore suggested that the presence of people near the arch could have influenced its stability. “Essentially, human activity doesn’t benefit an arch’s structural integrity,” he noted.

While an individual’s weight wouldn’t immediately impact the arch, Moore remarked that cumulative human actions may have adverse effects over time.

However, he admitted it’s challenging to assess exactly how much human behavior hastened the arch’s collapse.

“The arch would have eventually collapsed, regardless,” Moore said. “Did it happen sooner because of human interference? Likely, but the exact timeline is uncertain.”

At times, park officials have intervened to limit human impact on geological features. For instance, Canyonlands National Park, located northeast of Glen Canyon in Utah, restricts visitors from climbing on or near the arches.

Moore also cited airspace regulations around the Rainbow Bridge National Monument, a significant natural bridge, which were enforced due to studies indicating that helicopter traffic could harm the formation.

Did climate change cause the arch’s collapse?

Experts remain uncertain about the extent of climate change’s impact in this scenario.

“If there’s any link, it would be a weak one,” said Willis.

Recent collapses at Arches National Park

Double Arch is not alone; various arches have collapsed in recent years due to natural forces.

In 2008, Wall Arch, another natural formation in Arches National Park, dramatically fell. Campers nearby reported hearing what they believed was thunder, despite clear weather conditions, according to the park service.

Situated along the busy Devils Garden Trail, Wall Arch had been known for its unstable support – a piece of rock had previously broken off nearly 40 years before its collapse, as per the Utah Geological Survey.

Rainbow Arch, located near the park’s visitor center, collapsed in 2018.

On September 1, 1991, visitors to Landscape Arch heard cracking noises before a large rock fell, though the arch remained standing. Landscape Arch spans over 300 feet, making it the longest arch on the continent.

Willis warned that Landscape Arch is aging and could collapse soon.

“It’s quite old,” he said. “When I observe it, I wonder how it remains upright.”

The ongoing wear and tear of these natural wonders adds to their allure, according to Moore. “These arches are typically in a fragile balance,” he explained. “While the changes appear slow to us, they are actively evolving.”

“It might take thousands of years to achieve a form, and in that sense, we’re fortunate to witness them at this moment in time,” he concluded.