Marsh Lake Dam

• Published in: Canadian Journal of Civil Engineering
• Main Authors: Thompson, W. J., Engweiler, J. A., Gilbert-Green, J. A., Gordon, J. L., Shery, R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1978
• Subjects: General Environmental Science; Civil and Structural Engineering; Yukon; Canada; Marsh lake; Whitehorse; Yukon river
• Online Access: http://dx.doi.org/10.1139/l78-019; http://www.nrcresearchpress.com/doi/pdf/10.1139/l78-019

The paper describes the design and construction of a steel cantilever dam on the Yukon River, approximately 24 km upstream of Whitehorse. The dam can retain 2.4 m of water to store a volume of 1.02 × 10 9 m 3 for use at the Whitehorse Hydroelectric Power Plant. Although the dam is small by today's standards, its design and construction posed several interesting problems, which were overcome by an innovative structure that was built on a pervious foundation, without the benefit of cofferdams, without diversion and with little obstruction to the flow of the river.The design concept has not previously been used in Canada and utilizes a combination arrangement of H-section piles, interconnected with Z-sheet pile sections to form a continuous steel wall. Alternate H-piles extend above this wall to provide openings for vertical lift gates and to support a prefabricated steel deck. The pile driving equipment worked from this deck when driving subsequent piles. Prefabricated gate guides were positioned between the extended H-piles and held in place with tremie concrete.The dam was constructed in approximately half the time and at about half the cost that would have been required for a conventional concrete structure.