Sugar Lake Dam is situated on the Shuswap River at the outlet of Sugar Lake and is approximately 70 km east of Vernon, BC. The dam provides storage and flow regulation for the Wilsey Dam, 29 km downstream on the Shuswap River and for the Shuswap Falls generating station located at the Wilsey Dam. The dam was constructed in 1929 and it was a 5.2 m-high concrete buttress overflow dam with a timber upstream face. In 1942, the dam was raised and the concrete gravity low-level outlet section and the non-overflow section were added. In 1975, the timber upstream face on the concrete buttresses was replaced with precast concrete planks.
Klohn Crippen Berger was retained by BC Hydro to perform a Dam Safety Review (DSR) of the Sugar Lake Dam in accordance with the requirements of the statutory BC Dam Safety Regulation, BC Hydro’s policies and standards, and CDA Dam Safety Guidelines. The scope of work included the review of all existing data, site visit, review of dam safety management procedures, design and construction details, operation maintenance and surveillance procedures and emergency plans. A Hazards and Failure Modes Matrix was also completed for the dam at the same time as the Dam Safety Review. This analysis identified all probable external and internal hazards imposed on the dam and the associated failure modes. The Hazards and Failure Modes Matrix was used with the standards-based review to obtain a broader understanding of the safety management of the dam. A detailed DSR report was produced which included any identified deficiencies or non-conformances and the recommended prioritization to resolve the deficiencies or non-conformances.