The steamer was carrying a crew of twenty-five men and a full cargo, including cattle and three tons (2.722 t) of blasting powder destined for the Tantalus coal mine, thirty miles (48 km) downriver.

[2] On the day of the accident, the Columbian was carrying only one passenger: Ernest Wynstanley, a stowaway who had sneaked aboard, pretending to be the caretaker of the cattle on board.

The 1906 season crew included J. O. Williams, captain; H. C. Baughman, mate; A. Borrowman, steward; Lionel Cadogan Cowper, purser; Carl Christianson (shipping on as "J. Smith"), deckhand and coal trimmer; A. D. Lewis, chief engineer; Frank J. Mavis, second engineer; Edward Morgan, fireman; Phil Murray, deckboy; C. D. Phillips, deckboy; C. Smith, purser; Joe Welsh, mate; and John Woods, deckhand.

[2] The explosion happened after Murray passed his illicitly-held loaded rifle to Morgan, so that the fireman could take pot shots at a flock of ducks on the water.

Following the ensuing explosion and fire, the captain grounded the ship on shore; those not killed or injured by the blast jumped ashore to safety.

[1] The explosion blew out the sides of the vessel, scattered men and cargo in the water, and in less than five minutes had involved the whole inside of the ship in a mass of seething flame.

The body of Welsh was found in November on a bar in the Yukon River between Tantalus and Five Fingers, about twenty-five to thirty miles (40 to 48 km) below the site of the disaster.