Hydrothermal Explosion Occurs at Biscuit Basin in Yellowstone National Park

A hydrothermal explosion occurred at Biscuit Basin in Yellowstone National Park on June 13, 2026, at 5:09 a.m. local time. The blast produced no injuries and created a new pool along with multiple vents, @ABC reported.

The basin sits less than 2 miles northwest of Old Faithful. Monitoring equipment recorded seismic activity and infrasound from the direction of the Black Diamond Pool before the explosion. Park rangers later observed light-gray to milky runoff in the Firehole River downstream from the site.

Geologists identified three sets of newly formed vents in the Black Diamond Pool. One vent formed a crack measuring about 61 feet long and 5 feet wide in places. A second linear vent to the northeast measured about 49 feet long.

Water temperatures at the vents ranged from 185 to 200 degrees Fahrenheit. A fissure about 61 feet long filled with near-boiling water opened during the event. A camera installed at the Black Diamond Pool in 2025 captured a dark-colored stream jetting from the ground north of the pool.

Between the afternoon of June 14 and the morning of June 16, a new pool of vigorously boiling gray water full of silt formed near the middle vent group through land collapse. Camera observations on June 18 showed intermittent spouting reaching 20 to 30 feet, with active boiling when not spouting.

Biscuit Basin has remained closed since a prior hydrothermal explosion at the Black Diamond Pool on July 23, 2024.

Temporary seismic monitoring stations have been installed in the basin to track signals from the new vents.