It was on this day in 1917, that catastrophe struck the Treadwell and Mexican Mines on Douglas Island at 12:35 am.

The mines that were below sea level on Douglas Island, across the Gastinou Channel from Juneau, began leaking the evening before, and the miners were evacuated. Then just after midnight, the mines collapsed due to 3 million gallons flooding into the mines.

Because of the evacuation, no miners were injured or died in the collapse of the largest mining complex in the world, but 12 horses and a mule perished as 200-foot geysers spewed from the entrances.

The flooding of seawater would close three of the four mines forever.

  1917, collapse, douglas, flooding, mines, treadwell