Thermal Activity Closes One Yellowstone National Park Trail, Repairwork Allows Three Others to Reopen

Thermal activity along the Clear Lake Trail, which offers views of the Lower Falls of the Yellowstone, has prompted Yellowstone National Park officials to temporarily close the trail. Kurt Repanshek photo.

A newly discovered "hot spot" has led to temporary closure of the Clear Lake Trail in Yellowstone National Park, but elsewhere in the park completed repairs have allowed officials to reopen three other trails.

The 1.5-mile-long Clear Lake Trail climbs up onto a plateau that provides you with nice views of both the Upper and Lower Falls of the Yellowstone River. It also takes you into one of the park's many thermally active areas. Yellowstone officials announced Wednesday that they were temporarily closing the trail because of new thermal activity along the trail that could prove hazardous to hikers.

"The 'hot spots' indicate a heat source under the crust of the trail. These hot spots will be evaluated by park geology staff using thermal imaging and a ground survey," park officials said in a release. "The ground survey will include additional thermal infrared imaging and a direct measurement of ground temperatures. In select areas of concern, ground temperatures will be measured at a variety of depths to assess heat flow and potential areas of thin crust.

"Depending on the findings and before the trail can be reopened, it may be necessary to re-route the trail or build boardwalk over the hot spots."

Elsewhere in the park, repairs to a section of boardwalk in the Back Basin of Norris Geyser Basin, to the stairs down Uncle Tom’s Trail along the South Rim of the Grand Canyon of the Yellowstone, and to the Wraith Falls Trail have been completed. All three trails have reopened to the public.