Hebgen Lake Earthquake Devastated Area 60 Years Ago

It’s been 60 Years Since the Hebgen Lake Earthquake, which re-shaped parts of Yellowstone National Park and made a lasting impact on the geography – and the people.

At 11:37 pm August 17, 1959, campers along the Madison River west of Yellowstone National Park awoke to a nightmare. Trees swayed and snapped as the earth shook. Then, a deafening roar filled the air as 80 million tons of dirt, rock, and debris careened at 100 mph over their campsites and into Madison Canyon.

Nineteen campers died beneath the slide that evening. Others lost their lives to hurricane-force winds and a muddy wall of water exploding from the Madison River.

Help was delayed because of limited communications and road damage. At least 28 people eventually lost their lives during the Hebgen Lake Earthquake.

The quake registered between 7.3 and 7.5 on the Richter scale and remains among the strongest earthquakes on record in North America. Although the initial event lasted only 30–40 seconds, the after-effects were catastrophic.

The day of the earthquake, and immediately thereafter, hundreds of geysers in the park erupted, including many hot springs. Most hydrothermal features returned to pre-quake activity within a year, although some features experienced long-term changes. A few of those changes include Old Faithful, which exhibited a tendency toward longer intervals between eruptions; Giantess Geyser’s active phase, which usually lasts between 1 and 43 hours, lasted more than 100 hours; and Sapphire Pool in Biscuit Basin experienced eruptions nearly 125 feet high and wide.

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