Salmon River Diversion Dam Decommissioning

ACEC-BC Award of Merit

The Salmon River Diversion Dam, located on Vancouver Island, was built in 1958 to divert flow from the Salmon River into the Lower Campbell Reservoir to increase the capacity of the Ladore and John Hart Hydro Facilities. KCB and Hatch Ltd. were engaged by project owner BC Hydro to develop a plan for the dam’s decommissioning and restoration of the Salmon River channel. BC Hydro together with Wei Wai Kum and We Wai Kai First Nations co-managed the project from planning through to implementation and completion.

Challenges

  • Ageing dam infrastructure required costly rehabilitation to continue operations
  • Fish passage was hindered by the dam
  • Dam infrastructure was made of creosote-treated timber, leading to potential site contamination

Solutions

  • Dam was decommissioned by removing diversion dam, headworks structures, and timber flume in the diversion canal
  • Natural flow of Salmon River was restored allowing for unhindered fish passage upstream
  • Dam was carefully dismantled and disposed of to avoid site contamination

Successes

  • Dam was removed within approved environmental instream work window, minimizing impact to fish
  • Disturbed areas in and around decommissioning sites were restored
  • Final result received favourably by First Nations, community stakeholders and government agencies, who were successfully engaged throughout the project duration