The Harbour Collision that Flattened a City: Halifax 1917

Halifax, Nova Scotia, nineteen seventeen. A burning ship drifts toward the waterfront. Twenty minutes later, by most accounts, the largest man-made explosion the world has yet seen devastates a city. Here is how it happened.

Start with the setting. Halifax is a port city on the east coast of Canada, and in December nineteen seventeen, the First World War is in its fourth year. Halifax has a deep natural harbour, so it has become a base for the navy and a gathering place for convoys of ships bound for Europe. They carry soldiers, food, and munitions. To guard against submarines, a steel net closes the harbour at night and opens in the morning. The rules about dangerous cargo have been relaxed. About sixty thousand people live in Halifax and its neighbour Dartmouth, many of them right beside the docks. On the morning of December sixth, two ships are heading for the same narrow channel.

The first is the Mont-Blanc, a French cargo steamer about three hundred and twenty feet long. Her cargo would be dangerous anywhere: about twenty-eight hundred tons of explosives, mostly picric acid and TNT, and barrels of a flammable fuel called benzol stacked on her deck. She arrived from New York too late the night before to get through the net, so she is going in now. The second ship is the Imo, a Norwegian steamer, longer, at about four hundred and thirty feet. Her captain is Haakon From, and a harbour pilot, William Hayes, is on board. She is empty, on her way to New York to collect relief supplies for Belgium. But her coal arrived late, which cost her a day. By most accounts, she is now in a hurry, well over the harbour's five knot speed limit. Both ships enter the Narrows, the channel between the outer harbour and a large anchorage called Bedford Basin. The rule is to keep to your own side. The Imo, avoiding other traffic, has ended up on the wrong one.

The Mont-Blanc's pilot, Francis Mackey, gives one whistle blast, claiming right of way. The Imo answers with two. Both ships cut their engines, but momentum carries them together, and the Imo's reversing propeller swings her bow into the Mont-Blanc. The impact is slow, only about one knot. But barrels of benzol split open, sparks ignite the vapour, and the Mont-Blanc is on fire. Her captain, Aimé Le Médec, knows what she carries. He orders everyone to abandon ship, and the crew row for the Dartmouth shore. The burning ship, with no one aboard, drifts across the harbour and comes to rest at Pier 6, in a district called Richmond, at the edge of the city. And thousands of people can see her.

Then something terrible happens, and it is completely ordinary. People stop to watch. A burning ship is a spectacle. They stand at windows, on rooftops, along the waterfront. Firefighters race to Pier 6, and a tugboat, the Stella Maris, steams back to spray the flames. None of them know what is in the hold. Nearby, in the railway yard, a dispatcher named Vince Coleman learns that the ship is loaded with explosives. By the usual account, he starts to run. Then he remembers the overnight train from Saint John, with nearly three hundred passengers, due at the station beside the harbour. He goes back to his telegraph key, and sends a message down the line. Hold up the train. Ammunition ship afire in harbour, making for Pier 6, and will explode. Then: Guess this will be my last message. Good-bye, boys.

At four minutes past nine, about twenty minutes after the collision, the Mont-Blanc explodes. By modern estimates, the blast equals roughly three thousand tons of TNT. A column of smoke and debris climbs more than three kilometres into the sky. The ship's anchor is thrown over three kilometres, and one of her guns, more than five. Nearly everything within eight hundred metres is obliterated, including most of Richmond. For a moment, the harbour floor is bare, and then a wave up to eighteen metres high sweeps over the shore. People who had stopped to watch at windows are hit by a storm of glass, and hundreds are blinded. Overturned stoves and lamps set the wooden houses of the North End alight. In seconds, a city is broken. In the rail yard, Vince Coleman is killed at his key.

Survivors dig out their neighbours with bare hands. Soldiers, sailors, firefighters, and anyone with a vehicle carry the wounded away. The military hospital at Camp Hill admits about fourteen hundred people that day. Relief trains arrive from across Nova Scotia and New Brunswick. Then the next day, a blizzard buries the ruins under more than forty centimetres of snow, and stalls the trains. Help still comes. From Boston, in the United States, trains bring medical teams and supplies. When the count is finished, close to two thousand people are dead, and about nine thousand are injured. The exact number of dead has never been settled. As for Coleman, historians still debate whether his message stopped the train. What is certain is that he sent it.

Within a week, an inquiry opens to ask who was at fault. Its report, in February nineteen eighteen, blames the Mont-Blanc's captain, Aimé Le Médec, her pilot, Francis Mackey, and Commander Evan Wyatt. All three are charged with manslaughter. The charges against Le Médec and Mackey are dropped, and a jury acquits Wyatt. In the civil courts, a first ruling in April nineteen eighteen puts all the blame on the Mont-Blanc. Then, on appeal, Canada's Supreme Court in nineteen nineteen, and the Privy Council in London in nineteen twenty, decide that both ships were equally to blame. No one is ever convicted. The Imo's captain, Haakon From, and her pilot, William Hayes, were killed on her bridge. The Imo had been going too fast, on the wrong side of the channel. The Mont-Blanc had turned across her path, carrying a cargo that was never meant to enter a busy harbour. The argument about it has never entirely ended.

Halifax rebuilds. A relief commission, formed around noon that same day, will run until nineteen seventy-six. Planners design a new Richmond from a fireproof building material called Hydrostone: three hundred and twenty-six homes on tree-lined streets, with the first families moving in by March nineteen nineteen. Not everyone shares in the rebuilding. The nearby community of Africville, also hit, receives none of the reconstruction investment. And in nineteen eighteen, Halifax sends a Christmas tree to Boston, to say thank you. The gift was revived in nineteen seventy-one, and every year since, a tree from Nova Scotia has stood in Boston. It is a thank-you for what began on a December morning, with two ships in a narrow channel, in Halifax, Nova Scotia, nineteen seventeen.