2020 CANADIAN CONSULTING ENGINEERING AWARDS
NATURAL RESOURCES, MINING, INDUSTRY AND ENERGY
AWARD OF EXCELLENCE
Grand Falls Dam and Spillway Rehabilitation
HATCH
“We are impressed they were able to accomplish so much in such a short time and avoid risk to the environment and public safety.” –Jury 54
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CCE_OctNov2020_AMS.indd 54
Built in 1909, Newfoundland's Grand Falls Dam eventually deteriorated to the point where remedial repairs were required. The contractor, Pennecon, asked Hatch to devise a rehabilitation scheme to replace an existing design that posed constructability and safety concerns. Hatch met this challenge with a new design within a month. One of the keys to the success of the new concept was the application of advanced hydrotechnical principles, which demonstrated the earlier design’s 10 inflatable gates could be replaced with a simple passive,
stepped overflow weir immediately downstream of the existing spillway. Hatch’s solution eliminated constructability and safety concerns associated with the original design. Advanced computational fluid dynamics (CFD) analyses were performed to verify the ogee-shaped weir’s discharge capacity and energy dissipation step heights, so as to better suit the contractor’s preference for formwork that further reduced costs and improved the schedule. The design was also specifically tailored to ensure there would be no interruption to power generation,
October/November 2020
2020-10-05 9:16 AM
