Columbia Power Corporation and Columbia Basin Trust are partners in an effort to build more than 700 MW of hydro capacity in British Columbia, Canada. Two projects – Arrow Lakes and the Brilliant Expansion – are complete. Development work is beginning on the third, the Waneta Expansion.
By William P. Clark and Gay H. Grant
One of the newest hydro generating facilities to begin operating in British Columbia is the 120-MW Brilliant Expansion Project on the Lower Kootenay River. In commercial operation since September 2007, the plant was built adjacent to the existing Brilliant Dam and 145-MW generating station.
The Brilliant Expansion is the second of three projects mandated to be built by Columbia Power Corporation and Columbia Basin Trust (CBT). This unique partnership shares revenues from the sale of electricity from the three projects between the province of British Columbia (represented by Columbia Power) and CBT.
Before beginning work on the Brilliant Expansion, the partners constructed a 185-MW powerhouse, the Arrow Lakes Generating Station, adjacent to BC Hydro’s Hugh Keenleyside Dam. Now that the Brilliant Expansion is complete, Columbia Power and CBT are working on the Waneta Expansion, which will have a capacity of up to 435 MW.
Forming the partnership
The Columbia Basin Trust Act of 1995 created CBT to provide benefits to the region most directly affected by the Columbia River Treaty dams. The treaty, signed in 1964 between Canada and the U.S., authorized construction of four dams intended to improve flood control and power production. Arrow Dam (later renamed Hugh Keenleyside Dam) was completed in 1968; Duncan Dam on the Kootenay River was completed in 1970; Mica Dam on the Columbia River, upstream of Keenleyside, was completed in 1973; and Libby Dam, on the Kootenay River in Montana, was completed in 1975.
These four dams store spring runoff; control flooding in Washington and Oregon; and release water during the summer, fall, and winter for hydro plants on the Columbia River in the U.S. This water allows for a total additional capacity of 2,400 MW. In exchange for building the dams and storing water, British Columbia receives one-half of the generation from the 2,400 MW, known as the “downstream benefits.”
Although these four dams improved flood control and power production, the resulting reservoirs in Canada flooded large sections of important valley bottom land. This flooding inundated traditional First Nations’ land, took highly productive agricultural and forestry areas out of the local economy, displaced communities, and destroyed fish and wildlife habitats.
In the early 1990s, citizens, local governments, and Tribal Council leaders formed the Columbia River Treaty Committee, which took the region’s concerns to the province. In 1995, the province of British Columbia provided a C$321 million (US$272 million) endowment to be invested, managed, and distributed to the region through establishment of the CBT. From this endowment, C$276 million (US$234 million) was earmarked to finance power project construction. The CBT has two core functions:
– To invest capital and manage the assets of the CBT; and
– To spend the income earned from the CBT’s investments to deliver benefits to the Columbia Basin.
In 1994, the province formed Columbia Power. British Columbia committed to provide C$250 million (US$212 million) over a ten-year period for the development of three core power projects in the Columbia Basin, in partnership with CBT. These projects were: the addition of power generation at Hugh Keenleyside Dam and the expansion of generating capacities at Brilliant Dam and Waneta Dam, both of which were owned by Teck Cominco Metals Ltd. The partners purchased Brilliant Dam from Teck Cominco in 1996 and invested C$100 million (US$85 million) to upgrade the dam and increase the life span and reliability of the power plant. The upgrades began in 1996 and were completed in 2003. Work included concrete rehabilitation, seismic stabilization, turbine upgrades, and construction of a new switchyard.
Fifty percent of the net profits from power sales go to CBT to create a legacy of social, economic, and environmental well-being for residents of the Columbia Basin and to achieve greater self-sufficiency for present and future generations. CBT assists communities by providing resources and funding; focusing on local priorities and issues; bringing people together around key issues; providing useful, credible, and accessible information; encouraging collaboration and partnerships; and seeking ongoing input from Basin residents.
Developing Arrow Lakes
Construction of the partners’ first project, Keenleyside (now known as the 185-MW Arrow Lakes Generating Station), began in March 1999. The powerhouse, which contains two Kaplan units, is located in a bedrock outcrop 400 meters downstream from the dam. The powerhouse uses water that normally would be spilled over the dam. Under a 12-year power sales agreement, the project owners deliver power to BC Hydro via a new 230-kilovolt transmission line.
To ensure the project did not go over its C$250 million (US$212 million) budget, Columbia Power used a “design-build” approach and added a “go or no go” step. In this final step, the corporation warned that even the most creative and efficient design-build proposal might not make the project viable. Calling its process design-evaluate-build, Columbia Power solicited expressions of interest in 1997 and pre-qualified three teams to enter the proposal competition stage. In July 1998, the three teams submitted proposals. After evaluating the proposals, Arrow Lakes Power Company (a joint venture of Columbia Power and CBT) entered into a C$210 million (US$178 million) design-build contract with the winning bidder: Peter Kiewit Sons Co. Ltd., MWH, and GE Hydro Canada.
The first unit produced power in November 2001, and the project entered commercial operation in February 2002. The Arrow Lakes project provides 800 gigawatt-hours of electricity each year. The success of this project showed the partners that development of the other two hydro projects mandated by the agreement was possible.
Building Brilliant Expansion
When the hydro plant at Brilliant Dam began operating in 1944, it was the last in a cascade of five stations to be built on the Lower Kootenay River. The four upstream plants, owned and operated by FortisBC, are 51-MW Corra Linn, 59-MW Upper Bonnington, 41-MW Lower Bonnington, and 53-MW South Slocan. The city of Nelson, British Columbia, operates a 16-MW plant at Bonnington Falls.
When Brilliant was designed in the late 1930s, the flow profile of the Lower Kootenay River was influenced by both the natural storage in Kootenay Lake and the limited control of lake levels provided by Corra Linn Dam under the terms of an International Joint Commission (IJC) Order. Otherwise, flows were unregulated. The annual hydrograph exhibited the typical pattern of peak flows in May to June and low flows in September to October and March to April. The original design capacity at Brilliant Dam was selected to recognize natural low flows and to be in relative hydraulic balance with the existing upstream power plant capacity.
Two of the storage dams built under the Columbia River Treaty – Duncan in Canada and Libby in the U.S. – altered the flow hydrograph for the Lower Kootenay (and Brilliant) by reducing peak flows and increasing low flows. Taking advantage of this flow regulation, BC Hydro constructed the 572.2-MW Kootenay Canal Generating Station in 1976. The effect of these developments is that for much of the year, most Kootenay River flows are diverted around the four FortisBC plants to take advantage of the greater head at Kootenay Canal and the higher efficiency of its generating units.
The Brilliant Dam turbine upgrade, which began in 2000 and was completed in 2002, consisted of upgrading the four turbines in the original powerhouse. This upgrade raised the hydraulic capacity of the Brilliant powerhouse to 610 cubic meters per second (cms) from its original 509 cms. This increased the total generating capacity to 148 MW from its original 129 MW. However, the upgrade “maxed out” the water processing capabilities of the powerhouse.
To harness more of the remaining spill opportunity, Columbia Power proposed building a dam bypass channel to a new powerhouse on the left bank. This concept would avoid the considerable risk and cost of undertaking heavy civil work on the main dam and powerhouse. The bypass concept allowed for the new powerhouse to be built “in the dry.” In addition, tailrace improvements intended to increase head at Brilliant Dam would be carried out during construction of the new powerhouse, increasing generation at the existing plant.
Public consultation for the expansion began in 2000, and certification under the province’s Environmental Assessment Act was received in the fall of 2001. Columbia Power and CBT continued with the design-evaluate-build approach that was used for construction of Arrow Lakes. Bids were evaluated during the first half of 2002, and the Brilliant Expansion Consortium (a joint venture of Swedish company Skanska International Civil Engineering AB and Alberta-based Chant Construction, and SNC-Lavalin, with Alstom Canada supplying the generator and turbine) was awarded the $167 million (US$141 million) contract, which was signed in February 2003.
A significant requirement for the contractors of the Brilliant Expansion was fostering economic development throughout the region. This included hiring local people for the construction project, improving infrastructure in the region, and procuring equipment and special services locally when possible. In addition, an 18-member committee was formed to act as a conduit between all parties to mitigate negative effects from project construction (such as dust, traffic concerns, and effects to recreation) and keep the community apprised. The committee met monthly during the construction period and was made up of local residents, municipal government leaders, and representatives from the project partners and contractor. The committee was integral to the development and selection of the indicators that would be used to measure the social and economic effects, both positive and negative, of the project. These indicators formed the basis of a quarterly Socio-Economic Monitoring Report for the Brilliant Expansion project, which was made available the public on Columbia Power’s website.
Overall, the project met or exceeded almost all of its indicator targets during the four-year construction period, including employment levels and income, local hiring, and equity employment. The local hiring requirement of the project – 85 percent of workers originating from within 100 kilometers of the project site – was exceeded in 2004, 2006, and 2007. During those years, local workers comprised an average 88 percent of the workforce. The project also exceeded its goals for equity employment – women, First Nations, visible minority, and disabled employees – with these groups of workers making up, on average, 16 percent of the labor force over the course of the project. Total employment income for the project was more than C$51 million (US$43 million), far exceeding the estimated target of C$27 million (US$23 million). And total local contractor expenditures were C$52.5 million (US$44 million), 425 percent higher than targeted, due to the contractor being able to source more material and labor from the immediate area than was initially planned.
Power sales agreement
In November 2003, Brilliant Expansion Power Corporation, a subsidiary of Columbia Power and CBT, reached a power sales agreement with BC Hydro for 40 percent, or 203 gigawatt-hours (GWh) annually, of Brilliant Expansion power. Brilliant Expansion Power made another bid to sell most of the remaining electricity to BC Hydro during its 2006 Open Call for Power and sold another 50 percent, or 226 GWh annually. The remaining 10 percent would be sold by Brilliant Expansion Power into the short-term power market.
Challenges of development
The 16-story powerhouse for the project contained a single 120-MW Kaplan turbine supplied by Alstom. A 244-meter-long access tunnel was drilled through solid rock, providing road access from Brilliant Dam to the new powerhouse. Access also was provided by a 1.2-kilometer-long road along the left bank. In addition, a 140-meter-long adit tunnel was drilled to assist in excavation of the 170-meter-long power tunnel, which would convey water from the intake to the turbine.
Project construction involved some challenges. One was the close proximity of Brilliant Dam; another was that the Kootenay River below Brilliant Dam – the site of the expansion project – was home to a number of endangered white sturgeon. Planning for the project had to take these important factors into account. Accordingly, protective measures were specified in the design-build contract and the contractor developed an environmental management plan to protect the sturgeon. Because blasting in the river was considered the main threat to sturgeon, some measures put into place included hiring of a fisheries consultant from Golder Associates to monitor sturgeon presence before blasting and blasting through rock work pads to physically exclude sturgeon from the danger zone.1 Other general preventive measures included providing sturgeon awareness training to all workers involved in the in-river work and having an environmental monitor on-site during in-river work.
The new powerhouse being added to Waneta Dam in British Columbia will boost capacity by up to 435 MW. Construction could begin as early as the summer of 2009 and be complete in four to five years.
During removal of the upstream rock plug at the intake area, a bubble curtain was used to dissipate blast shock waves.1 As the shock waves passed through the bubble curtain, they lost energy, thus protecting the intake gates at Brilliant Dam. Because both the rock work pads and bubble curtain were used in conjunction with engineered, controlled blasting, they were very effective. No damage to Brilliant Dam occurred, and no sturgeon or other fish were killed as a result of the blasting.
The Brilliant Expansion project began commercial operation in September 2007.
Planning for Waneta Expansion
The partners currently are working on development of the Waneta Expansion, located at Teck Cominco’s Waneta Dam. The dam already supplies water for a 400-MW powerhouse that began operating in 1954. The expansion will share the dam’s hydraulic head and make use of water flows that otherwise would be spilled. The partners acquired the rights to use this hydraulic head, as well as the land necessary to build the expansion project, from Teck Cominco in 1994.
The base concept for the Waneta Expansion is structured to avoid environmental effects on white sturgeon habitat at the confluence of the Columbia and Pend d’Oreille rivers. Water will be conveyed through two tunnels from the Waneta forebay into a two-unit powerhouse to be built “in the dry” on the right bank of the Pend d’Oreille River. Output from the units will be stepped up to 230 kilovolts and connected through powerhouse switching equipment to a new 10-kilometer-long transmission line that will join the project to the Selkirk Substation near the Canada/U.S. border.
The addition of up to 435 MW of capacity at Waneta will achieve balance with upstream generation at 804-MW Seven Mile Dam, owned by BC Hydro, and 1,051-MW Boundary Dam, owned by Seattle City Light. (The Pend d’Oreille River flows north from Boundary into Canada.) This hydraulic balance will allow flows released from Boundary Dam to travel the Canadian section of the Pend d’Oreille River without the need for reservoir re-regulation to avoid spill. Minimizing re-regulation will increase the productivity of reservoir aquatic habitat. In addition, diverting otherwise unavoidable spill through the Waneta Expansion will reduce harmful dissolved gas supersaturation in waters below Waneta Dam and down the Columbia River into the U.S.
The project is in the request for proposals stage, and three companies have committed themselves to develop proposals to construct the project. They are Peter Kiewit Sons Co., SNC-Lavalin Inc., and a joint venture of Bilfinger Berger Inc. and North America Construction Ltd.
Following an evaluation of the proposals in the spring of 2009, Columbia Power and CBT will reassess the viability of the project. Depending on the outcome, construction could begin as early as the fall of 2009 and be complete in four to five years.
Looking into the future
The Waneta expansion is the third and final project mandated by the province of British Columbia to be constructed by Columbia Power and CBT. Columbia Power will soon begin working with its board of directors and then it shareholder – the province of British Columbia – to determine the company’s direction after the Waneta expansion work is complete.
- ” Techniques Minimize Effects of Blasting on Structures, Fish,” Hydro Review, Volume 27, No. 4, July 2008, page 76.
Bill Clark, P.Eng., is manager of project services/coordination and Gay Grant is community relations coordinator with Columbia Power Corporation.