Canada remembers Great Halifax Explosion on 100th anniversary of largest blast of pre-atomic era
05 December 2017
On December 6th, 1917, the French cargo ship SS Mont-Blanc, having left New York loaded with explosives destined for the Allied war effort in Europe, collided with the New York-bound Norwegian vessel SS Imo in the harbour at Halifax, Nova Scotia. The resulting fire set off an explosion that flattened large parts of the city, killed at least 2,000 and injured a further 9,000.
Halifax harbour after the blast - Image: Nova Scotia Archives
The harbour had been crowded with vessels organising for a military convoy and were hampered in their movements by underwater anti-submarine nets, protection from the increasing threat of German U-boat attacks.
The impact of the two vessels occurred at about 8:45 am. The Mont Blanc ignited, and the fire quickly went out of control. Sailors on other ships, dock and factory workers, military personnel and residents, including children on the way to school, gathered to watch the blazing ship.
In addition to its full cargo of TNT, the ship’s hull and deck were crammed with barrels of highly flammable benzole (a fuel) and picric acid (an explosive) as well as guncotton (a propellant or low-order explosive). This made the Mont-Blanc a massive bomb, and 20 minutes after the collision it went off.
The sudden, massive and deafening fireball flattened a 3.5 square-kilometre area, killing approximately 2,000 people and injuring 9,000. This was the largest man-made explosion before nuclear weapons - the equivalent of 2,989 tonnes of TNT.
Nearly all structures within an 800-metre radius, including the entire community of Richmond, were obliterated. A pressure wave snapped trees, bent iron rails, demolished buildings, grounded vessels, and scattered fragments of the Mont-Blanc for kilometres. Hardly a window in the city proper survived the blast. Across the harbour, in Dartmouth, there was also widespread damage. A tsunami created by the blast wiped out the community of Mi'kmaq First Nations people who had lived in the Tufts Cove area for generations.
Twenty-five thousand were left without shelter. Debris was scattered over a wide area and windows shattered up to 85 kilometres away, blinding many. Yet another cruel blow was to come the next day when a blizzard blanketed the area, hampering relief efforts as snow covered the dead and dying.
The Nova Scotia provincial government is involved in a number of activities to commemorate those who were killed and injured in the disaster, while local and national media have published special reports into the incident and its subsequent consequences.