Catastrophe: 1917 Explosion in Halifax, Canada
We had just drawn soap and powder, and the necessary utensils for cleaning paint work when the most awful explosion I ever heard, or want to hear again, occurred. —Frank Baker, ship inspector, HMCS Arcadia
By Roger Childs
Halifax, the capital of the Canadian province of Nova Scotia, is remembered as being the closest port to the Titanic sinking. Most of the survivors and the recovered bodies were taken to the city in April 1912.
However, five and a half years later, a much bigger disaster occurred when a French munitions ship collided with a Norwegian freighter in the narrow entrance to Halifax harbour. The Mont Blanc caught fire and twenty minutes later exploded in the biggest non-nuclear, man-made conflagration in human history.
The consequences for the prosperous city were appalling.
Halifax: doing well during the Great War
When war broke out in 1914, Canada, like New Zealand and Australia, was quick to join the mother country. Located on the Atlantic seaboard, it naturally became a major demarcation point for Canadian troops heading for Britain and the Western Front.
Hundreds of ships carrying supplies and munitions to Europe also set out from Halifax. The on-going war effort meant that industries expanded in the city and nearby towns, and labourers flowed in from other areas in Canada.
Consequently there was a residential boom and the population grew rapidly.
Ships in The Narrows
The Narrows leading to the harbour are little more than a kilometre wide. In-coming ships have right of way. The Mont Blanc was coming in from New York to join a military convoy in the large Bedford Basin, and would sail with it on the trans-Atlantic crossing to Britain.
It had a full cargo of highly explosive matériel:
- 2367 metric tons of picric acid
- 250 metric tons of TNT
- 246 metric tons of the high octane gasoline benzol
- 62 metric tons of gun cotton
The French ship should have been flying a red flag to indicate it was carrying a dangerous cargo.
Meanwhile the Imo, which was a Norwegian ship carrying relief supplies for the Belgian war effort, was heading out to sea. It would stop off at New York before sailing across to Europe.
The captain had been frustrated because the ship had been delayed for several days. Consequently, he set sail without the harbour master’s permission.
At first he was not prepared to give way to the Mont Blanc. Eventually, when the Imo did start turning away, it couldn’t do so fast enough to avoid a collision.
A devastating impact
The two ships collided at about 8.45 am on 6 December 1917. The picric acid caught fire and the crew abandoned ship. Thousands of people were on their way to work and school, and gathered on the waterfront to watch the spectacle.
The burning ship set a wharf alight and then at 9:04 am the Mont Blanc exploded in a blinding white flash: an explosion equivalent to a 2.9 kiloton blast.
Windows were shattered in buildings within a radius of 80 km and the noise was heard much further away
The spectators on the waterfront never stood a chance, neither did those who were watching near windows. Over 1800 were killed and more than 9000 were injured.
The northern end of Halifax was levelled as were parts of Richmond. More than 1600 homes were destroyed as well as factories, businesses, hotels, public buildings and sports facilities.
A newspaper headline read HALIFAX IN RUINS, STREETS LITTERED WITH THE DEAD
And to compound the misery of the survivors, the worst blizzard of the year swept through the city that night.
A full account is in Michael J. Bird’s book The Town That Died.