The William B. Rankine Generating Station
of the Canadian Niagara Power Company
Niagara Falls, Ontario. Commissioned 1905. Decommissioned 2005.
Exploring the Rankine Tailrace
The William B. Rankine Generating Station is the last intact example of the mammoth engineering projects that pioneered the industrial-scale production of electricity at Niagara Falls between 1893 and 1906. Built to the same basic form as that introduced in the Niagara Power Company's Adams station, the Rankine facility was maintained in an operational shape until decommissioning in 2005, and remains in excellent condition. As the rest of the region's hydroelectric heritage was demolished, gutted, or left to rot, we owe a great deal to Fortis Ontario the station's last operator prior to it reverting to Niagara Parks Commission control with the conclusion of the site's lease in 2009 for preserving not just the structure but its incredible internal mechanisms. Thanks to the work of Fortis, and Norman Ball, whose The Canadian Niagara Power Company Story was commissioned by the company to celebrate its hundredth anniversary, we also know an enormous amount about the station's history. It is now incumbent on the Niagara Parks Commission, government, and private investors to secure a future for Rankine before neglect and inertia send this fascinating place to the same fate as befell the Toronto Power Generating Station and the Ontario Generating Station.
Like the other early hydroelectric developments at Niagara, the Rankine station was built by private investors, in this case the Canadian Niagara Power Company. The company was part of a complicated web of industrial and land development ventures that included the Niagara Power Company and Cataract Construction Company on the American side, and shared many of the same directors and financial backers. As Norman Ball relates in his history, the station's eventual namesake, William Birch Rankine, featured prominently in many of these companies.
The Canadian Niagara Power Company had originally signed a contract with the Niagara Parks Commission in 1892 for monopoly rights to generate power within the Commission's land on the Ontario side of the Falls, but its failure to promptly begin construction (its investors, directors, and suppliers were all busy building the Niagara Power Company's stations on the New York side) and growing public discontent with the terms of the deal led the Ontario Legislature to cancel the CNPCo monopoly in 1899, and authorize the Parks Commission to negotiate with other parties interested in developing the Niagara River's hydroelectric potential. While CNPCo. was able to renegotiate its lease and ultimately move forward with its planned development, two other concerns the American-owned Ontario Power Company, and the Electrical Development Company (later called the Toronto Power Company), a Canadian/British-venture led by Sir Henry Pellatt quickly tied up similar deals.
A construction boom followed as all three ventures pushed ahead with their plans, and by 1906 three separate powerhouses were producing power at industrial scales on the Canadian side of the falls. However, by the mid-1920s, these other companies had been bought out by the new public power authority, the Hydroelectric Power Commission of Ontario (HEPCO), and only the Canadian Niagara Power Company remained with a private power lease at the Canadian Niagara Falls. In 1950, CNPCo., along with the Niagara Power Company, was bought by Niagara Mohawk, which held the monopoly on electrical distribution in the northern part of New York State. In 1996, Fortis bought 50% of CNPCo., and eventually purchased the rest of the company.
Into the Depths
Descending the Rankine wheelpit on foot is an unbelievable experience. The deep wheelpit stations at Niagara were in many ways like icebergs: while their above-ground powerhouses were large and majestic, their presence gave little hint to the vast cavernous space that had been opened up below them. These wheelpits, and the machinery they contain, are the critical component of the architecture of these power stations, and at Rankine this underground system has until recently been kept lit, maintained and preserved.
While most people lucky enough to have received a tour of the station will have likely seen the wheelpit via a quick elevator ride to the bottom, we had to do it the hard way, descending a long series of steeply angled ladder stairs between the main bearing decks and the intermediate platforms that surround each turbine shaft all the way down. Unlike in the wheelpit of the Toronto Power Generating Station a few hundred metres up the river, there are no stairs.
As you descend these ladders, you are suspended within the incredible line of ten-foot-diameter penstocks and tree-trunk-thick turbine shafts that once fed energy down and then back up this 150 foot deep gash that was torn from the shale bedrock with drills and explosives. 28 inches of brick may lie between the atmosphere of the pit and the rock that presses in against it, but the rock is all you feel down there, the rock and the moisture that wets each breath you take. Apparently the lights have now been turned off, a money-saving measure no doubt though it does little to make an observer feel good about the plant's future, but when we were there everything was still lit in warm incandescence, making the photographs on this page possible.
Against the Earth
To my knowledge, the Rankine G.S. was one of just four powerhouses, all at Niagara, that were ever built with such an enormously deep wheelpit (136 feet from generator to turbine, with another forty-some feet below that given over to structural supports and the tailrace tunnel), and the only intact example remaining: the two Adams stations on the New York side were demolished in 1961, while the Toronto Power Generating Station was allowed to decay after its decommissioning in 1973, and most of the equipment and fittings were scrapped from its forebay, powerhouse and thrust deck in 2006. In its depth, the deep wheelpit design shared by these stations had an inherent disadvantage over the compact systems favoured in more modern powerhouses. Over time the long drive shafts that stretched back up to the surface fell victim to the movement of the rock surrounding the pit, shifting slowly out of a true vertical alignment. To a certain extent, this movement could be compensated for by adjusting the large bearings that supported each drive shaft, but ultimately geology must win out.
At Rankine, Norman Ball tells us that this movement was discovered in 1902 while excavation of the wheelpit was still ongoing.1 Heavy cast iron struts were installed across the pit between the turbines of units 4 and 5, seated in castings that had been included in the wheelpit design after similar rock movement was detected at the Adams plant five years earlier. Movement continues to this dayin 2005 a crack formed in the wheelpit wall, requiring additional reinforcement work.
Turbines and Exciters
The turbines at Rankine are hard to wrap your head around, as the majority of each wheel case (where water actually spins the turbine's blades and drives the shaft that reaches back up to the alternators on the surface) is positioned below the floor of the turbine deck. Instead, most of what we see are century-old control equipment: the levers and gears that are connected to the flyball speed governors back on the surface and direct valves that control the flow of water into each turbine, manual valve control wheels, and devices to adjust the drive shaft alignment. Smaller water and oil lines run, bracketed, along the walls.
Five arched chambers open into the wheelpit along the east wall. These chambers were meant to hold exciters, small direct-current generators driven by their own small penstock lines that provide the electricity necessary to create electromagnetic fields in the alternators up in the powerhouse (through which conductive brushes are spun by the rotation of the turbines to generate far greater amounts of alternating current), and some of them still do, while others now sit (or perhaps always were) empty. In a few places, stairs and hatches provide access down to the rack deck, a dark space with a steel grille floor. The rack deck feels like a cellar, and is the final level above the draft chamber that water from the turbines flows out into on its way to the tailrace.
And then there's the tailrace. You can read about that in this separate article.
- 1. Norman R. Ball. 2006. The Canadian Niagara Power Company Story. Boston Mills Press, 61-62.
Michael Cook is available to speak to your organization about infrastructure history, lost creeks, current conditions, and opportunities for change in our management of and communication about urban watersheds, and to work with teams proposing or implementing such change. Get in touch.