Due to thermal activity, rangers have closed the Upper Terrace Drive in the Mammoth Hot Springs area to cars.
The thermal activity began in May; it even generated small terraces near the road, giving off large amounts of heat. Geologists and rangers monitoring the feature found it was, at times, about 152 degrees Fahrenheit. In addition, said geologists and rangers noticed thermal activity near and under the pavement adjacent to the new feature, proved by thermal imaging.
“We have known this area had heat near the surface based on the fact that it does not hold snow in the winter,” said Dr. Hank Heasler, park geologist, in a National Park Service Yellowstone press release. “We drilled two holes a half-meter (20 inches) deep, both of which now have hot water bubbling at the surface or very near the surface.”
Although the Upper Terrace Drive is closed to vehicular traffic, it is open to pedestrian traffic. Currently, maintenance staff is building a buffer of logs to protect both visitors and the thermal feature. Once the buffer is built, cars will be allowed on the road once more.
The news comes as a bit of surprise, but it’s a wonderful example of how quickly (and suddenly) both infrastructure and thermal features in Yellowstone National Park. It’s not as dramatic as, say, the explosion of Porkchop Geyser back in 1989. Nonetheless, just because it isn’t exploding doesn’t mean it isn’t very interesting in its own right.