Dominion, Cape Breton, was called Old Bridgeport until 1893 when the Dominion Coal Company opened the Dominion No. 1-A Colliery.

The Dominion Coal Company was established that year by Henry Melville Whitney, one of the many larger-than-life figures who played key roles in Nova Scotia’s mining and industrial history. Whitney also founded the Dominion Iron and Steel Company to build the Sydney steel plant (Cape Breton’s Whitney Pier is named for him.)

Whitney consolidated under his ownership practically all the coal mines operating in the Sydney coalfield east of Sydney Harbour.

The Dominion No. 1-A Colliery was opened to work the Phalen coal seam through three shafts, each 154 feet deep. Two-thirds of 1-A mined underground and one-third mined under the ocean.

On March 19, 1903, an underground fire started about 1200 feet from the pit bottom and 147 feet below sea level.

It was assumed that the fire was caused by a workman carelessly throwing away a lighted wick. The fire could not be controlled, so the decision was made to flood the mine to put it out.

That probably sounds easier than it actually was.

About 576 million gallons of water were needed to bring the water level above the fire but the maximum drainage available from the surface was 1350 gallons per minute. At that rate, it would take at least 296 days to extinguish the fire, so it was decided to flood the mine from the ocean.

This was accomplished by driving a tunnel 119 feet long, six feet high and six feet wide from the shore, between the low and high tide marks, so sea water would fill the tunnel as the tide rose. The tunnel was driven in just four days, an average of 30 feet per day, and the fire was put out.

The fire and flooding caused the mine to shut down for about fifteen months. When it reopened, it mined only underground, much of it under the town, until it shut down permanently in 1927. In total, Dominion No. 1-A produced 13,202,419 long tons.

There was still a lot of coal in 1-A’s flooded submarine tunnels so air and hoisting shafts were sunk near the shore in 1922 and 1923. They became the Dominion No. 1-B mine which opened in June 1924 to continue mining the undersea area of the Phalen coal seam that 1-A had abandoned.

Dominion No. 1-B operated until 1955 and produced 17,022,961 long tons of coal.

1-A and 1-B are part of a series of ten interconnected mines that mined different areas and/or different coal seams. Many of Nova Scotia’s historical underground coal mines were interconnected this way, usually for practical reasons such as facilitating air circulation and reducing costs by sharing shafts and tunnels. Unfortunately, these connections also sometimes allowed flooding and fires to spread from one mine to others.

Because of these underground connections, a pumping station in 1-B was kept operational for many years after 1-B closed in order to keep several other mines from filling with water. Water inflow is a constant in most mines and pumps are used to keep them dry. When a mine shuts down, the pumps are ordinarily removed, allowing the mine to fill with water. In the case of 1-B, the pumps continued to operate because allowing 1-B to fill would have flooded other connected mines.

The pumping station in 1-B kept dry the 1-A, 1-B, No. 2, No. 5 and No. 26 collieries. Mine water was pumped to the surface from 1-B for more than 50 years at a rate of 1750 gallons per minute (gpm).

The No. 26 Colliery was lost to a mine fire in 1984 and a decision was made in 1985 to shut off the 1-B pumps. This led to the flooding of these inactive mines.

The problem is there were two mines within the group of ten that were still operating - the Lingan and Phalen collieries – and underground dam failures caused inrushes of water into these two mines. One such incident occurred in 1992 and resulted in a sustained, major inrush (up to 7000 gpm) through the now-compromised barrier pillar that had been designed to separate the workings of the Lingan and No. 26 collieries. Pumping was immediately re-established in 1-B in the hope that the Lingan Colliery could be saved.

However, it did not work and Lingan shut down in 1993 after it was determined that it was no longer safe to work the mine with the high risk of catastrophic mine water inrushes.

Phalen Colliery continued to mine directly below the flooded workings of Lingan and No. 26, with 425-feet of vertical separation, until 1999. In its final years, 1200 gpm leaked steadily into Phalen from the mines above, and there were also several large flushes of water from them. However, the Phalen pumping system was upgraded to handle the increased water.

It is said, but not documented, that until No. 26 closed in 1985, at least one worker walked every day from the 1-B shafts to the 1-A water level (about 3.5 kilometres) to ensure its stability in case miners in No. 26 needed that route for an emergency exit.

A "colliery" is a coal mine and its associated buildings. Colliery only refers to coal mines, not other types of mines, because it's an alternate spelling of "coalery," a word that is no longer used.

While Nova Scotia's use of coal is declining, it still provides over half of our electricity and it has powered our economy for centuries.

Dominion 1B plant
Dominion 1B wharf
Dominion 1B plant