Melting roads in Yellowstone National Park are real — but not a reason to panic

Roads in Yellowstone are melting “like silly putty.” They’re covered in ripples and potholes, and they’re getting warmed from under the Earth’s surface.

But that’s not a reason to panic, experts at the U.S. Geological Survey said.

In 2014, a 4.8-magnitude earthquake rattled Yellowstone National Park and caused fears that a volcanic eruption was coming.

For years, people have worried earthquakes in Yellowstone are a sign that the “supervolcano” that lies beneath the park will soon erupt. It could have regional and global consequences.

“Such a giant eruption would have regional effects such as falling ash and short-term (years to decades) changes to global climate,” USGS said on its website. “Those parts of the surrounding states of Montana, Idaho, and Wyoming that are closest to Yellowstone would be affected by pyroclastic flows, while other places in the United States would be impacted by falling ash.”

Geologists don’t think an eruption at Yellowstone is likely for thousands of years, but that doesn’t stop misinformation from spreading.

After the earthquake in 2014, people began to think nearly anything could be a sign of an impending eruption.

Bison ran through the park, and people said video showed they were “running for their lives,” the USGS said. People also noticed roads in Yellowstone were warping in the heat.

“The ‘melting road’ of 2014 fame was Firehole Lake Drive, which is located in the Lower Geyser Basin of Yellowstone National Park,” USGS said in a Sept. 12 Facebook post. “During the summer of that year, the road was closed for a few days because the asphalt in certain areas was starting to fail.”

The road stretches over a large thermal area of the park, and it had a history of warping the asphalt before 2014. The road gets heat from underground and from above during the summer months.

“The result of this heating is that the asphalt softens and can flow, like silly putty,” geologists said. “This can create ‘ripples’ in the road surface, and potholes are more likely to form.”

When cars go over the hot asphalt, that can cause more damage. Other roads throughout the park have also been warped by the heat, experts said.

The famous Old Faithful geyser, as well as other thermal features, have caused constant problems on roads.

While it is an ongoing problem in the park, experts said it’s nothing to worry about.

“Do roads sometimes ‘melt’ in Yellowstone National Park? The phrasing is a bit melodramatic, but indeed, roads can be impacted by the thermal ground they traverse,” USGS said. “This is nothing new, nor a sign of imminent volcanic activity.”

This story was originally published September 13, 2022 at 12:26 PM with the headline "Melting roads in Yellowstone National Park are real — but not a reason to panic."