Yellowstone hydrothermal explosion leaves pools "overflowing" as hazards remain, officials say
Two pools at Yellowstone National Park are overflowing and the area remains hazardous for visitors two days after a hydrothermal explosion in the park's Biscuit Basin.
An underground stream of water beneath the park's Black Diamond Pool suddenly turned to steam, throwing boiling water and hot rocks high into the air just before 10 a.m. local time on Tuesday, July 23. Since gas takes up more space than liquid, there isn't enough room for the substances to exist, which causes an explosion, the Weather Channel's Stephanie Abrams told CBS News.
Typically, this results in the geysers and hot springs Yellowstone is known for, but on Tuesday, it resulted in an explosion that sent steam and debris "hundreds of feet above the ground," according to the National Parks Service. A boardwalk was destroyed, nearby trees were killed, and "grapefruit-sized rocks" were thrown into the air. Some blocks of debris weigh hundreds of pounds and are about 3 feet wide, the NPS said. No one was hurt in the explosion, though visitors were in the area.
The debris remained in the area as of Thursday morning.
The Black Diamond Pool and the nearby Black Opal Pool also remain disrupted by the explosion. The shape of the Black Diamond Pool has "changed somewhat," the NPS said, though the agency did not specify how. Debris has made the two pools murky, and the ground around them is now unstable, so earth occasionally slides into the water.
Both pools are also overflowing with water. That water is now being sent to the nearby Firehole River.
The NPS said that "small explosions of boiling water" will be possible in the area in the coming days to months. Experts will monitor conditions in the Biscuit Basin and monitor the hydrothermal systems where the gas buildup initially occurred, the agency said.
The Biscuit Basin will be closed for the rest of the year for visitor safety, the NPS said. Nearby thermal basins remain open to visitors.
