Remember This? The Chaudière Ring Dam

OttawaMatters.com, in partnership with the Historical Society of Ottawa, brings you this weekly feature by Director James Powell, highlighting a moment in the city's history.

December 19, 1908

It would be hard to underestimate the importance of the Chaudière Falls to the development of the city of Ottawa. 

Along with the Rideau Canal, the city owes its existence to the power that was (and continues to be) generated at the falls. One could argue that without the falls, the lumber industry, which was the economic life blood of the city through the nineteenth century, would have located elsewhere. And without its mills, it’s hard to imagine that little Ottawa would have been a viable candidate to be the capital of Canada in 1857, notwithstanding its ideal location.

From the early nineteenth century, settlers recognized the energy potential of the falls. Lumber mills popped up on both sides of the Ottawa River as well as on the islands that straddle the border between Ontario and Quebec, including the Wright’s, Chaudière, Victoria, Albert and Amelia Islands. Logs cut in the Ottawa hinterland were floated down the river and its tributaries to these mills. In the years before electricity, the mills were powered by water wheels.

By the early 1880s, water-powered turbines had advanced to the point where it was economic to convert the energy of flowing water into electricity. The first hydro-electric plant in North America opened in 1881 on the U.S. side of the Niagara Falls. That same year, E.B. Eddy used a generator run by waterpower to power arc lights in his lumber, match and woodenware factory in Hull.

By the mid-1890s, Ottawa was known as the “Electric City,” due importantly to the development of electrical power made possible by harnessing the Chaudière Falls. At the time, it was estimated that 20 per cent of Ottawa’s population and 75 per cent of Hull’s population were directly dependent on the falls for their livelihoods.

The two men most responsible for this electrical revolution were Thomas Ahearn and Warren Soper. Ahearn was an inventor par excellence, Canada’s answer to Thomas Edison, while Warren Soper was the man with the business acumen. Together, the duo formed a powerful partnership that dominated Ottawa for a generation. In 1896, the Illustrated Buffalo Express newspaper wrote:

“Through the splendid supply of cheap power afforded by the falls, combined with the business foresight and ability of two of its citizens [Ahearn and Soper], Ottawa has led the van, not only for the Dominion but also in many respects for the continent, in the way of the development of practical electricity.”

In addition to powering a timber industry worth $5-million per year (a huge sum in those days), Ahearn and Soper’s Ottawa Electric Company provided power to many Ottawa-area businesses — as long as they were located within four miles of the generators at the Chaudière Falls. The Canadian Atlantic Railway Company’s repair shops in LeBreton Flats were powered by electricity. R.A. McCormick, a pharmacy on Spark Street, was heated electrically. The Ottawa Canoe Club even used an electric motor for hauling canoes out of the water. Ahearn and Soper’s electric railway system was also powered by hydro-electricity. The streetcar system had thirty miles of track with 40 cars running daily through the year. The streetcars were heated and lighted electrically, unheard of luxuries just a few years earlier.

The Ottawa Electric Company also provided street lighting throughout the city as well power for most of the 60,000 incandescent light bulbs in use in Ottawa at that time. The Buffalo newspaper enthused that is amounted to more than one bulb for every inhabitant, “a proportion claimed to be unequal by any other town of like size in America.”

While less expensive than using manufactured gas to light lamps, electricity did not come cheap, notwithstanding what the Buffalo newspaper said. In 1903, electricity reportedly cost 8 cents per kilowatt hour in Ottawa, equivalent to roughly $2 per kilowatt hour in 2019 dollars. The 2019 Ottawa Hydro’s off-peak rate is 6.5 cents a kilowatt hour.

Growing demand for electricity as electrical lines were strung across the city, combined with economic growth, led to pressures to increase the production of hydro power at the falls. However, conflicting interests and bickering among the power owners at the Chaudière caused long delays. 

On the Ottawa side of the river alone, there were 26 water lots lettered A to Z, most of which were controlled by electric power generators, lumber and flour companies. These lots were leased from the Dominion government for $100 per year. Added to the complexity of the problem was the fact that any agreement among the Ontario and Quebec power owners at the Grand Chaudière Falls had to respect the rights of power owners at the upstream Little Chaudière Falls. While the Dominion government recognized the importance of developing water power on the Ottawa River, it was not going to move until the private power owners came up with a solution to their disagreements.

In 1907, a settlement was finally reached among the water powers on the Ottawa River that settled “the vexed and prolonged differences between the users of water power at the Chaudière Falls.” 

The agreement was executed on the Ontario side by J.R. Booth, the Ottawa Electric Company, the Ottawa Electric Railway Company, the Ottawa Power Company, the Bronson Company, and the Ottawa Investment Company. On the Quebec side were the E.B. Eddy Company and the Ottawa and Hull Power Company. To facilitate matters, Thomas Ahearn and the Ottawa Land Association gave up their water rights at the Little Chaudière Falls.

The agreement was quite simple, and hugely profitable for the power producers. 

The Ontario and Quebec companies would share the water equally. They would also build a modern dam at the Chaudière Falls, replacing the existing submerged dam built forty years earlier. The new dam would raise the head of water at the cost of partially drowning the Little Chaudière Falls. 

For its part, the Dominion government would dam the upper reaches of the Ottawa river. By storing water upstream, water could be saved during the spring freshet and slowly released during the low water months of later summer and autumn. A steady, regulated flow of water would allow the hydro turbines to run more consistently and efficiently through the year. It would also improve navigation on the Ottawa River. As well, spring flooding would be mitigated. 

The City of Ottawa would also benefit. A higher water level behind a new dam would reduce the problem of anchor and frazil ice in the winter that blocked intakes to the City’s waterworks located upstream from the Falls. Anchor ice is submerged ice that forms in face-moving rivers at very low temperatures. Frazil ice is slushy ice that also forms in turbulent, super cold water.

Work began on a new dam in early August 1908 and proceeded rapidly in part owing to the Ottawa River’s extraordinarily low water level that year. The power owners established a committee in charge of the work consisting of George Millen, representing the north shore owners, William Baldwin, representing the south shore owners, and two engineers, J.B. McRae and William Kennedy Jr. Messrs. Quinlan and Robinson of Montreal were the contractors. 

The site’s superintendent was Mr. J. B. Laflamme who had considerable experience, having worked on the bridge across the Rio Grande River between the United States and Mexico at Eagle Pass and on the Trent Valley Canal. He kept a firm grip on the workers. He is reported as saying, “Two things I do not permit among my men are swearing and drinking.” In charge of the concrete gangs was Uldric Marcotte would had worked on the piers for the Quebec bridge and the power dam on the Severn River at Ragged Rapids.

The first task was to take some two thousand soundings to determine the elevation of the river bed. 

Tests were also done to determine the velocity of the water at various points. Detailed drawings and specifications were approved for the contracts for concrete, steelwork, etc. Divers also cleaned the river bed. A temporary road to transport supplies to the site from the Chaudière Bridge was constructed along with a tool house, cement shed and a store shed.

Work began on the dam proper in late August on the Quebec side. Work commenced on the Ontario side shortly afterwards. As many as three hundred men were employed on the site working day and night to ensure that the dam was completed before the end of the season. The cost was $250,000.

The dam consisted of 49 concrete piers and two abutments constructed in the form of an arc of a circle with a radius of 546 feet, 9 inches, with the centre of the arc situated at a point within the Big Kettle of the Falls. Each pier was made of reinforced concrete, with steel rods bolted together. 1¾ inch anchor bolts fasten the rods to the bedrock of the river. To construct the piers, a wooden mould, made exactly to the shape of the pier, was filled with concrete and allowed to set. Each pier was 39 feet 5 inches long and four feet thick on the upstream side and 2 feet thick on the downstream side. To protect them from ice floes in the winter, the upstream sides were faced with a curved ½ inch steel plate.

The final pier was completed at 2:45 p.m. on Saturday, December 19, 1908. 

When the last bucket of concrete was poured, workmen hoisted the Union Jack on an improvised flagstaff in the presence of the engineers and representatives of the contractor. So accurately were the piers positioned, that holes drilled in the steel beams that connected the tops of the piers were only ½ inch out when the final pier was connected.

In total, the construction of the Chaudière Ring Dam entailed the excavation of 7,400 cubic yards of rock, the laying of 8,926 cubic yards of concrete, and the installation of 700 tons of steel.

To regulate the flow of the river through the dam, large stoplogs of British Columbian Douglas fir were purchased from Cameron & Company, and transported by rail across the country, arriving in Ottawa by mid-November. There were 550 pieces, totally more than 300,000 board feet of lumber. According to their position in the dam, the logs, each roughly 24 feet long, came in three sizes, 14 inches x 16 inches, 16 inches x 16 inches, and 16 inches by 18 inches. They were lowered between the piers by an electrically-operated, travelling winch with a lifting capacity of 50 tons. The winch travelled along a rail laid on top of a concrete road that connected the piers.

By the summer of 1909, several thousand horse-power of electricity was ready for sale at $15 per horse power per year, equivalent to 1.7 cents per kilowatt hour. 14,000 additional horse-power (roughly 10 Megawatts) could be made available with the installation of additional generators. Once the government had completed the water storage dams on the Upper Ottawa, many times that amount could be generated.

The Chaudière Ring Dam was the principal source of electrical power in Ottawa for the next twenty years. By 1928, however, electrical demand finally outstripped what could be generated at the falls. Increasingly, additional power had to be purchased from the Hydro-Electric Power Commission of Ontario, later known as Ontario Hydro.

Today, the Chaudière Ring Dam produces 84.6 Megawatts of clean, renewable hydro-electricity. This is enough power to supply 58,000 homes. 

All of the six hydro-electric facilities in operation at the Chaudière Falls on both sides of the Ottawa River are owned and operated by Portage Power, a subsidiary of Hydro Ottawa. This includes Canada’s oldest operating hydro-electric plant situated on Victoria Island, which dates back to 1891. 

In 2017, Generating Station No. 5 located on Chaudière Island, was opened. Its state-of-the art powerhouse with four turbines was constructed entirely below ground. This permitted the creation of the Chaudière Falls Park with a viewing platform over the Falls, thereby restoring public access to the area for the first time in over 100 years.  

To reinforce the eco-friendly nature of the new hydro facility, a fish ladder was installed to facilitate the migration of the American eel up the Ottawa River. As well, a sturgeon spawning bed was created to help restore the sturgeon population on the Ottawa River, devastated in the past by pollution.

Despite the environmental credentials of the hydro-electric facilities at the Chaudière Falls, the Chaudière Ring Dam remains controversial given its location at a site long considered sacred by Algonquin First Nations. The area, indeed all of Ottawa, remains unceded Algonquin territory. 

A “Free The Falls” group seeks the demolition of the Chaudière Ring Dam and the return of the Chaudière and Victoria Islands to their natural state or parkland.