Metro Vancouver has completed important work on the Cariboo Dam, a regional storm water facility near the east end of Burnaby Lake that controls the lake’s water levels and regulates inflows into the Brunette River.
Two adjustable gates – tainter gates – that control water flow rates were replaced after 84 years in operation. The old gates, made of steel and wood, were near the end of their service life, requiring frequent maintenance and repairs.
Burnaby Lake watershed is large and the lake level and the river inflows can increase suddenly during heavy rainfall. The Cariboo Dam plays a key role in balancing this drainage system and the two tainter gates are important components of the control system.
Liquid Waste Services Project Delivery was tasked with the replacement project, which took place between July and September 2019. The new stainless steel gates were manufactured by Mecan-Hydro Inc. located in Granby, Quebec.
In order to carry out in-stream work, part of the Brunette River needed to be isolated. Environmental professionals were on board throughout the work to monitor and manage the environmental impact to the surrounding ecosystem.
Burnaby Lake and the Brunette River support various types of aquatic species including species-at-risk such as Nooksack dace and western painted turtle. A critical Nooksack dace habitat is located immediately downstream of the dam and a constructed nesting habitat of western painted turtle is located just upstream of the dam. Both habitats were protected during construction.