Worst domestic tragedy in Canada, the biggest man-made, non-nuclear explosion in history.
In was December 6, 1917 and deadly war in Europe still dragged on with its massive destruction and horrific toll in lives.
Canada’s east coast port city of Halifax Nova Scotia, had become a main staging point and for years now had been a hive of activity and with dozens of ships waiting to leave, others to enter, and still others being loaded with supplies, munitions, and soldiers heading to the war. The main base of the Canadian Navy, and an important army garrison, Halifax had literally doubled in size during the war years.
This day dawned like many others and once the anti-submarine nets had been removed at the entrance to the “narrows” the heavy ship traffic starting to move in and out of the harbour.
Early in the morning of the 6th, a Norwegian ship “Imo“ chartered by the Belgian relief Commission, began slowly moving down the harbour on its way to New York to pick up relief supplies.
At the same time a fully loaded French munitions ship, Mont Blanc made its way into the narrows up towards the harbour toward its eventual station to join a convoy being formed which was later to sail to Europe.
The Mont Blanc was loaded to almost beyond capacity with about 3,000 tons of various highly explosive material. Although accounts vary as to the exact amount, there were about 2,300 tons of picric acid, 250 tons of TNT, 35 to 246 tons of benzol in barrels, and 10 to 62 tons of gun cotton
The mostly empty Imo, sitting high in the water, was difficult to steer and as it moved down the harbour. It was forced toward the Dartmouth shore to avoid a ship travelling up the narrows on the wrong side, and then further toward the Dartmouth side to avoid other traffic, This put it in line with the incoming MontBlanc. As they approached, both signalled that they had the right-of-way. Finally realizing a collision was imminent, the Imo stops then reverses as the Mont Blanc takes what it hoped was an evasive turn towards the Halifax shore in front of the Imo, but momentum carried the empty relief ship forward even as its reversed thrust caused the bow to swing into the munitions ship. The two ships collided at slow speed, but with enough impact to leave a gouge in the French ship knocking over the piled barrels of fuel and explosives piled on the deck.
An enormous floating bomb- on fire- abandoned, drifting to shore
It was 8;45 in the morning, as the Imo reversed out of the Mont Blanc. But with the grinding of metal on metal, sparks ignited the highly flammable liquids from som broken barrels.
The French ship’s crew makes a futile attempt to put the fire out which grows quickly out of control. They then hastily abandon ship knowing the danger but as they cry warnings to others about the ship, no one seems to understand, perhaps because they’re yelling in French
Normally a munitions ship would have been flying flags indicating the dangerous cargo, but in wartime this would have made it a prime U-boat target, so no flags, and again no general awareness of the extreme danger as the now burning ship drifts to the Halifax side of the harbour where it comes up against a pier, setting it ablaze.
People begin to gather to watch the fire of what they presumed was a simple cargo vessel.
Firefighters arrived and just as they were setting up, a blinding flash at 9;05 instantly levels most of Halifax especially the north end, while the massive tsunami created by the explosion causes widespread damage across the harbor in Dartmouth where the Imo itself was carried.
Some 2,000 people are killed outright and 9.000 others injured, many blinded by flying broken glass as they looked out windows to see the burning ship in the harbour. The shock wave even broke windows in Truro 100 kilometres away and was even felt and heard hundreds of kilometers further.
The rescue effort began immediately as far as it could in the damaged city, but as people and aid began to be assembled to head toward Halifax, the efforts were further hampered by a bitter winter storm which arrived the following day and lasted for several days.
In terms of the combination of property damage and loss of life, it remains the worst disaster in Canadian history. The number of blinded people led to the creation of the Canadian Institute for the Blind
CBC 360 animation
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