Not Your Grandfathers Mining Industry, Nova Scotia, Canada

The Hydrostones

The historic Hydrostone neighbourhood was built to provide housing after the Halifax Explosion. Hydrostone isn't actually stone - it's concrete block finished with crushed granite to make it look like cut stone. It was an attractive, practical and cost-effective material for rebuilding after the tragedy.

On December 6, 1917 two ships collided in the Narrows of Halifax Harbour. One of the ships was carrying explosives and the resulting blast devastated much of the North End of Halifax and flattened wooden buildings on both sides of the Narrows. Many buildings that were not destroyed by the force of the explosion were destroyed by fires caused by overturned stoves.

The Halifax Relief Commission was established to deal with the tragedy’s aftermath, including building homes for the hundreds of homeless families. The rebuilding of the North End was the first planned housing project in Canada and the most ambitious utilization of concrete blocks undertaken up to that time.

George Ross of Montreal architectural firm Ross and Macdonald offered his services at a bargain rate. He wanted to build an attractive, English-style garden suburb. Not surprisingly given the circumstances, he also wanted to ensure the homes were fire-resistant. He decided on Hydrostone for the exterior of the houses because it was stronger and more fire-resistant than wood.

Hydrostone, which is a brand name, not a type of rock, was made of Portland cement, sand, water and gravel or crushed stone. (Gravel and crushed stone are both small rocks. The difference is that gravel is broken down naturally by weathering and erosion, while crushed stone is broken down by a machine, i.e. a rock crusher. Both are referred to as aggregate and used in concrete.)

Each Hydrostone block was moulded under 150,000 pounds of pressure to give it “a smaller percentage of [water] absorption than any other building material,” the Hydrostone Company of Chicago claimed in a 1919 advertisement that promoted Hydrostone as “The Material Used in Rebuilding Halifax”. “This pressure forces the excess moisture to the surface at all points and compacts the aggregates so closely that a perfect bond is insured, giving maximum density and strength.”

The blocks were manufactured at the Canadian Hydro-Stone Company’s plant in Eastern Passage and transported by narrow-gauge railway to a nearby dock for shipment to Halifax.

The huge quantity of Hydrostone needed for rebuilding led to hiring at the plant. The August 26, 1918 Halifax Herald contained a want ad for “100 handy men for Hydorstone Making.” (The misspelling of Hydrostone was in the actual ad.) It promised “Best wages paid. First class board on the job. Apply at works plant wharf or at 159 Upper Water Street.”

(The same edition also included a warning to owners of homes damaged in the Explosion not to give liquor during working hours to workmen repairing houses because “This seriously interferes with the general progress of the Reconstruction work….”)

In total, 325 homes were built in a 23-acre neighbourhood, plus a row of shops. City Planner Thomas Adam’s plan for the redevelopment also set aside the former Fort Needham military grounds as a hilltop public park with magnificent views of the city. 

On February 10, 1921 the Evening Echo newspaper ran several letters from children who were living in the new Hydrostone homes. Robert Noble, who sadly lost his father and brother in the Explosion, started his letter by writing: “I like my new home. I am not afraid of fire in the night there.”

Thanks to the Nova Scotia Archives for preserving so much of Nova Scotia’s history, including several items referenced above.