FortisBC Inc. on Nov. 14 filed with the British Columbia Utilities Commission its final submission in support of its ongoing June 29 application for a Certificate of Public Convenience and Necessity (CPCN) for the construction and operation of fourteen replacement spillway gates and upgrades to certain of the components of the associated structures at the Corra Linn Dam.
The Corra Linn Dam is the uppermost dam in a series of four FortisBC-owned dams on the Kootenay River, located approximately 15 kilometers downstream from the city of Nelson, B.C. The aggregate capacity of these four dams is 225 MW, with the Corra Linn Dam having a current generating capacity of 49.45 MW.
The key driver for this rehab project arises from recent amendments made to Canadian dam industry standards and British Columbia government regulations, which have resulted in the Corra Linn Dam being reclassified to an “extreme” consequence classification, and hence no longer complying with the regulated requirements. The reclassification of the Corra Linn Dam is due to the risk of loss of life in excess of 100 persons to a permanent population residing downstream of the dam. Dams with an “extreme” classification are required to withstand a specific “design earthquake” and “design flood”, and studies have determined that the Corra Linn Dam spillway gates and certain components of the associated structures are not presently able to withstand the “design earthquake” event. Accordingly, it has been determined that the spillway gates will require either substantial rehabilitation or replacement in order to satisfy industry standards and government regulations.
Based on the technical and financial assessments of the alternatives for this project, FortisBC has selected Alternative 4 (Gate Replacement) as the preferred alternative. The total initial capital cost of the project is expected to be C$62.694 million (as spent).
Said the company: “The Corra Linn Dam is integral in supplying clean, renewable hydroelectric power in British Columbia, and ensuring that the spillway gates continue to be operational and safe is important to the overall operation of the dam. The Project therefore contributes to FBC achieving electricity self-sufficiency, the generation of clean or renewable energy in BC, the reduction of greenhouse gas emissions for alternative energy sources, and maximizing the value of BC’s clean energy generation assets. In addition, the implementation of the Project and the associated construction will create jobs, encouraging economic development in the province.”