150 MW Kwalsa and Upper Stave Hydroelectric Project

150 MW Kwalsa and Upper Stave Hydroelectric Project

Peter Kiewit Infrastructure Co., Cloudworks Energy Inc. (construction phase), Innergex Renewable Energy Inc. (operations phase)

British Columbia, Canada

  • Project identification and optimization
  • Environmental studies and permitting
  • Geotechnical and site investigations
  • Terrain hazard assessment
  • Detailed design and construction supervision of 6 hydroelectric facilities, including inflatable rubber dams, vortex desanders, Coanda screen intakes, buried and soil restrained high pressure penstocks, Weholite (HDPE) low pressure penstocks, buried and surface mounted high pressure penstocks, powerhouses including Francis and Pelton units, fish ladders and fisheries enhancement channels, transmission lines, and substations
  • Hydraulic modelling of intakes, inflatable rubber dams, diversion weirs, cofferdams, and bridge structures
  • Project management
  • Construction quality assurance
  • Operational environmental monitoring
Project Overview

The Kwalsa and Upper Stave Hydroelectric Project includes six hydroelectric facilities with a total installed capacity of 150 MW and an interconnecting 138 kV transmission line. Four of the facilities are located in the upper Harrison Lake area and the other two facilities are located in the Upper Stave River area about 50 km north of Mission, British Columbia, Canada.

Project Role

The owner, contractor, Douglas First Nation, and Knight Piésold worked closely together to develop low impact hydroelectric projects, overcoming unique challenges while delivering under budget and ahead of schedule.

Knight Piésold initially worked for the former owner, Cloudworks Energy Inc., in identifying a number of potential hydroelectric sites for development, and then worked directly for the EPC contractor, Peter Kiewit Infrastructure Co., regarding all aspects of detailed design as well as construction quality assurance. The power produced by the facilities is integral in helping British Columbia attain its self-sufficiency and clean energy goals.

Since construction completion, Knight Piésold has provided ongoing operational environmental monitoring services to the current owner, Innergex Renewable Energy Inc. The monitoring services include the installation and maintenance of telemetry-based hydrometric streamflow gauging stations used to monitor environmental flow compliance and periodic monitoring of stream channel morphology to assess potential changes in aquatic habitat.


Award of Merit, Energy & Industry Category, Upper Stave Hydroelectric Project, 2011 ACEC-BC Awards for Engineering Excellence