Site C Clean Energy Project, British Columbia, Canada
Site C Clean Energy Project is a dam and hydroelectric generating station being developed in British Columbia, Canada. The project will have a total capacity of 1,100MW, and a potential annual generating capacity of 5,100GWh of clean and renewable electricity. It received environmental approval from the federal and provincial governments in October 2014.
British Columbia Hydro and Power Authority (BC Hydro) will own and operate the project.
Site C location details
Site C will be the third dam on the Peace River, which originates from the Rocky Mountains located in the north-eastern parts of British Columbia. The other two existing dams are W.A.C Bennett and the Peace Canyon dam, both are located upstream of the proposed Site C dam.
Site C is expected to require an investment of C$7.9bn ($7.907bn). Site preparation activities began in August 2015 and the dam is scheduled to start generating electricity by 2024.
The reservoir created by the dam will cover a surface area of 9,330ha, while the construction of the controversial dam is expected to flood approximately 5,550ha of land.
Approximately 35,000 jobs are expected to be created during the development and construction period, along with a further 10,000 direct construction positions.
Site C development and history
The project is being undertaken to fulfil British Columbia's growing electricity needs, which are expected to grow by approximately 20% to 40% in the next 20 years. If successful, it will be capable of serving 450,000 homes annually for 100 years.
The possibility of constructing the current proposed dam was first identified in the 1950s, although the preliminary design phase was first conducted in the 1970s.
An original layout of the design was completed in 1981 and further engineering activities were carried out between 1989 and 1991. BC Hydro then decided to upgrade the design to meet the current seismic, safety and environmental guidelines. This revised design was completed in 2010.
The announcement to proceed with project activities was made in April 2010, while the regulatory review phase of the project, including consultations with various bodies, was carried out between 2010 and early 2013.
In addition, the environmental impact statement (EIS) for the project was submitted to the Canadian Environmental Assessment Agency and the British Columbia Environmental Assessment Office in January 2013.
Site C Clean Energy Project and reservoir details
The proposed project will include an earthfill dam measuring 1,050m in length and 60m in height.
Site C's reservoir will stretch for 83km, and the dam will consist of a main spillway, an auxiliary overflow spillway, and inlet and outlet diversion tunnels. The main spillway will include seven gates and two cofferdams will be constructed as part of the dam construction.
The generating station will comprise power intakes, penstocks and six units, each with a capacity of 183MW.
The proposed dam will primarily use storage water from the existing Williston reservoir and re-use water from the existing dams upstream. This will enable the dam to generate approximately 35% of the energy produced at W.A.C Bennett dam by making use of just 5% of its reservoir area.
Dam construction and infrastructure
Concrete buttresses will be used to strengthen various structures, including the foundation of the power station, spillway and the wall of the valley in the south. This will provide seismic protection and structure stability.
Access roads and a temporary access bridge for transportation during the construction phase will also be constructed.
The project will also involve the realignment of six segments of Highway 29, covering a distance of roughly 30km.
Grid connection for the Canadian hydroelectric power project
Power generated by the new hydroelectric station will be transported to the existing Peace Canyon substation through two AC transmission lines with a rated capacity of 500kV, travelling a distance of approximately 77km.
Contractors involved with the Site C Clean Energy Project
Two Rivers Lodging Group was awarded a $470m eight-year contract for the design, construction, partial financing, operation and maintenance of worker accommodation at the Site C dam site.
Paul Paquette and Son's Contracting secured a contract for clearing the south bank of the Site C dam construction area. The scope of the contract includes the removal of 620ha of trees and vegetation, construction of temporary access roads, upgrade and maintenance of existing access roads, and collection and removal of waste wood.
Morgan Construction and Environmental received a contract for site preparation activities, including the construction of access roads and site clearance works on the north bank.
Peace River Hydro Partners was awarded a $1.75bn contract for the construction of earthfill dam, two diversion tunnels and a roller-compacted concrete foundation for the generating station and spillways.
The Sir Adam Beck (SAB) hydroelectric power generating complex is located at Queenston Heights, Ontario, Canada.