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

The massive 1917 disaster

By Roger Childs

Halifax, capital of the Canadian province of Nova Scotia, is remembered as being the closest port to the Titanic sinking in 1912 — but five years later it was the site of the world’s biggest non-nuclear explosion.

After the Titanic sank, most of the survivors and the recovered bodies were taken to Halifax in April 1912.

Then, in December 1917, 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 late exploded. It remains 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 ongoing war meant that industries expanded in Halifax and nearby communities, and labourers flowed in from other provinces.

Consequently, to cater for the rapidly growing population there was a boom in housing construction.

Ships in The Narrows

The Narrows are little more than a kilometre wide. In-coming ships have right of way. The Mont Blanc was arriving from New York to join a military convoy which would escort it to Europe. The ships would assemble in the large Bedford Basin inland from The Narrows.

It had a full cargo of highly explosive matériel:

• 2300 tons of picric acid
• 200 tons of TNT
• 35 tons of high octane gasoline
• 10 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 Belgian Relief ship carrying food and supplies, was heading out to sea.  It was planning to 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 taking evasive action, it couldn’t do so fast enough to avoid a collision.

A devastating impact

The two ships collided at about 8.45 am on December 6 1917. The picric acid on the Mont Blanc caught fire and the crew abandoned ship. Thousands of people on their way to work and school, gathered along the waterfront to watch the spectacle.

The burning ship set a wharf alight and then at 9.04am the Mont Blanc exploded in a blinding white flash: an explosion equivalent to a 2.9 kiloton blast. Temperatures of 5000 degrees Celsius were generated.

Windows were shattered in buildings within a radius of 80 kilometres and the noise was heard hundreds of kilometres 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.

One 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.

The title of Michael J Bird’s 1962 seminal account of the disaster, summed up the impact: The Town That Died.