Halifax had become the most important link between North America and Europe, overflowing with anxiety and uncertainty as the city boomed with war prosperity and many had already become accustomed to the new sights and sounds. The harbour was filled with boats and ships from all nationalities of our allies, entering and leaving, with many carrying supplies and soldiers off to fight in the Great War. German submarines lurked along the coast of Nova Scotia blocking off the harbour’s mouth with nets and forcing military personnel to closely monitor each ship's every move. It had already been three years since the start of WWI and many people had already fallen into new routines. This was the scene on the morning of Dec 6th, 1917. A date no Nova Scotian will ever forget.
On that particular morning, the French ship, The SS Mont Blanc, loaded with 2,300 tons of wet and dry picric acid, 200 tons of TNT, 35 tons of benzol and 10 tons of gun cotton, was anchored just outside the mouth of the harbour. She had arrived too late the night before and the submarine netting had already been pulled shut, leaving the ship, loaded with ammo, to spend the night outside the protected harbour. Because she was carrying explosives she was required to fly a red flag, but had taken the flag down the night prior to reduce the risk posed by German u-boats and had failed to put the flag back up when she entered the harbour.
Photo of the Mont Blanc
At around the same time, the Norwegian ship SS IMO, left the Bedford Basin loaded with supplies headed to Belgium to support the war efforts and started off through the “Narrows”. Nautical regulations state that ships in the harbour must pass each other on their port side, steering starboard, which means that each ship passes to the left of each other steering to their right. However, on that particular morning, the IMO meet an American ship which was docking on the Halifax side of the harbour and both captains agreed to pass on their starboard sides. The IMO remained in the port channel as it passed a tug boat at around 8:15AM.
Picture of Halifax Harbour and the “Narrows”
The IMO then noticed the Mont Blanc entering the harbour in the starboard channel, i.e. the Dartmouth side. The IMO, the larger of the ships, signaled to the Mont Blanc to change its course, unaware of the cargo she was carrying. The Mont Blanc counter signals to IMO to change its course since the Mont Blanc was technically in the right of way and carrying a delicate cargo. In the last minutes, both ships change it’s course and collided in the middle of the harbour causing the IMO’s bow to strike the starboard (right side) of the Mont Blanc, sparking the highly flammable picric acid and benzene almost instantly. Attempting to dislodge it’s prow, the IMO pulled back and created more sparks. The Mont Blanc’s crew, unable to reach the fire extinguishing equipment and aware the fire was rapidly spreading throughout, abandon ship. The French-speaking crew was unable to communicate just what cargo the Mont Blanc was carrying to others who came to the rescue. The crew rowed to the Dartmouth shore and watched helplessly as the TNT loaded ship drifted towards the shores of Halifax.
The Mont Blanc burned for twenty minutes towards the busy industrial Pier 6 in the working class section of Halifax’s North end. Many onlookers gathered near the shore to watch the burning ship, completely unaware of the danger. At around 9:05AM the Mont Blanc exploded.
Photo of the mushroom cloud taken from outside the harbour.
A giant mushroom cloud of fire rose almost 2 km in the air and could be seen from miles away. The displaced waters surrounding the ship caused a Tsunami-like wave to rise up to 18km high, engulfing the crew and captain of the IMO who were standing on deck.
Photo of the IMO aground after the explosion
Shards of hot metal and ash rained down upon Halifax and Dartmouth for 10 minutes following the blast. The explosion instantly demolished entire buildings, severely damaged houses, snapped trees in half and bent iron rails within a 1.6km radius. Pieces of the Mont Blanc were hurled as far away as the Northwest arm and Dartmouth.
Decimated buildings looking out towards Pier 8
North End of Halifax residential area after the blast
From here on, it gets much worst before it gets better. The explosion killed 1,600 people instantly, injured approximately 9,000 others, many of them severely, and left many people blinded by shards of glass that burst out of windows. Approximately 6,000 people were left completely homeless and 25,000 without adequate housing. It is rumoured that not a pane of glass was left intact across Halifax and Dartmouth. Fires broke out across the city due to the lit furnaces and stoves in the demolished and damaged buildings. By nightfall the city’s the North End was almost completely up in flames and by morning it was in ashes.