2025 #CCEAwards Showcase: Keeyask Generating Station

Photo courtesy Hatch.

Category: Water Resources

Award of Excellence winner: Hatch

Keeyask Generating Station, developed through the Keeyask Hydropower Limited Partnership (KHLP) between Manitoba Hydro and four First Nations, was completed in 2024 and now delivers 695 MW of energy. Hatch was involved with the project for more than 25 years, providing planning, environmental studies and the final design.

Using parametric and three-dimensional (3-D) modelling, innovations like column extenders, electrical safety measures and zebra mussel mitigations, the firm delivered a mix of consulting engineering services, construction support and commissioning assistance on the project, leading to the station’s successful operation ahead of schedule.

On Jan. 20, 2025, Manitoba set a new daily record for electricity demand, reaching a peak of 5,112 MW when temperatures in Winnipeg dropped to -33 C. The Keeyask Generating Station proved instrumental in helping Manitoba Hydro meet this demand.

A model for success

Hatch designed the station with support from experts across Canada, including consulting engineers with SNC-Lavalin (now AtkinsRéalis) and KGS Group. The project team applied advanced engineering techniques and technologies while incorporating multiple disciplines, including electrical, geotechnical, hydrotechnical, mechanical, structural and management support groups.

From the outset, Manitoba Hydro and Hatch developed a parametric model—a first for a generating station—to aid the turbine generator vendor in optimizing designs to balance unit sizes with excavation for the site conditions. The evaluation helped Manitoba Hydro obtain the best layout for the station on a quantifiable, measurable and justifiable basis.

Multidisciplinary teams collaborated to solve problems unique to cold-weather regions. The hydrotechnical team developed the final seven-bay spillway alignment, employing 3-D numerical hydraulic models and two physical hydraulic models to optimize the design and analyze the project’s hydraulic characteristics.

During detailed design, instrumentation data from Manitoba Hydro sites confirmed the Keeyask spillway might be susceptible to increased uplift pressures during winter. Using two-dimensional (2-D) thermal model analysis, the team evaluated the risk of the concrete/bedrock contact freezing during winter, which led to modifications to the spillway structure’s design parameters based on the resulting uplift criteria.

Extensive use of 3-D tools helped create interlinked models of earth structures, concrete/steel structures, major equipment and systems. Regular model reviews tracked the project’s design progress.

The station was designed for the extreme weather conditions of its northern location. Photo courtesy Hatch.

The general civil contractor accessed the project’s 3-D model regularly, facilitating the development of value-added engineering components, project visualization and construction planning. Prior to the preparation of the construction drawings, safety was addressed for the construction and operation stages with the involvement of contractor and operators, through model walk-throughs and a hazard and operability (HAZOP) analysis.

Detailed to an equivalent building information modelling (BIM) level of development (LOD) 400, the 3-D model facilitated clash detection to identify conflicts with reinforcement, piping and conduits. This in turn helped reduce field modifications, requests for information (RFIs) and non-conformance reports (NCRs), while aiding the development of construction schedules and costs. Manitoba Hydro took the model further with four-dimensional (4-D) simulations and construction progress measurement.

Focusing on safety and reliability, Hatch designed electrical systems for protection and control, station bonding and grounding and emergency backup power. The firm also worked with Bentley Systems to enhance its expertise with 3-D rebar in complex geometry profiles, as for the powerhouse draft tube. Models were detailed with construction joints, facilitating rebar automation and moving on to fabrication.

Design difficulties

Keeyask is located approximately 725 km northeast of Winnipeg. The difficulty of sourcing labour and replacement parts over long distances was factored into the design, as were the extreme weather conditions of the northern location.

The aforementioned column extender design was implemented as a strategic change during construction of the powerhouse, where an accelerated schedule allowed concrete placement to be sheltered from the harsh elements. The early installation of powerhouse overhead cranes further streamlined construction, with minimal disruptions to the concrete works and embedded electrical and mechanical systems. In the end, the column extender design enabled winter concreting to save an estimated eight months and $400 million.

The unexpected failure of an ice boom led to a rapid rise in water level, threatening to overtop the 1-km long cofferdam designed to protect the powerhouse excavation area. An emergency top-up design was rapidly constructed, with temperatures falling to -25 C. This swift and effective intervention successfully held back water, preventing a one-year delay and more than $100 million in losses.

The team also took on concrete repair due to a major pipe failure, a central dam realignment, decision flowcharts for dikes, alternative dike designs, electrical isolation of traffic barriers, winter startups for early commissioning, zebra mussel mitigation and various system reliability improvement tasks.

Large-scale but local

Ongoing efforts to provide socio-economic benefits were a priority throughout construction for KHLP, the partnership between Manitoba Hydro and the Tataskweyak Cree Nation, War Lake First Nation, York Factory First Nation and Fox Lake Cree Nation. Constructed within the ancestral homeland of all four partner First Nations, the project is Manitoba’s fourth largest generating station, with a planned 4,400 GWh of energy to be produced annually.

From the start of engineering, these team members collaborated on development of sedimentation, erosion and water quality assessments, as well as monitoring programs. Community representatives were trained in data monitoring objectives, procedures and measures relating to health and safety. Hatch helped Manitoba Hydro carry out an environmental impact assessment, along with technical reports to supplement an environmental impact statement.

The project created significant employment opportunities, generating more than 29,000 jobs during its construction phase and boosting the local economy. Approximately 70% of the workforce was from Manitoba, 40% was Indigenous and 19% was from partnered communities.

Manitoba Hydro’s instrumentation data confirmed the spillway might be susceptible to uplift pressures. The team modified the detailed design accordingly. Photo courtesy Hatch.

Assessing environmental impacts

Hatch also supported KHLP in conducting assessments to avoid, mitigate and compensate for environmental effects, using both technical studies and Indigenous knowledge.

Based on more than 10 years’ research into environmental impacts, the lowest reservoir level option was chosen. This decision resulted in a 75% reduction in flooding by scaling down from a 1,150-MW plant (which would flood around 180 km²) to a 695-MW configuration (flooding only about 45 km²), reducing generating capacity by 40% and exemplifying a balanced approach to environmental stewardship and project feasibility.

Special attention was paid to sensitive habitats and species, especially lake sturgeon, which has been assessed as endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Mitigation measures—including replacement of spawning habitat and a large-scale stocking program—were implemented to both maintain existing stocks and increase the population in the region.

Setting a benchmark

Having worked with Manitoba Hydro for more than 50 years, Hatch possessed a deep understanding of the business environment, key performance indicators (KPIs) and stakeholders’ goals and requirements. The firm anticipated and addressed the client’s needs efficiently.

The project team surpassed a revised projected schedule with a five-month advancement and a corresponding reduction in the cost forecast. While the final unit has been contributing energy for Manitobans since Mar. 9, 2022, the design was completed in 2024, incorporating post-commissioning changes and as-builts.

Keeyask has also earned the distinction of becoming the first North American hydroelectric project to be evaluated under the International Hydropower Association’s (IHA’s) Hydropower Sustainability Assessment Protocol (HSAP), setting a benchmark for best practices in project development.

Keeyask Generating Station, Stephens Lake, Man.

Award-winning firm (owner’s engineer services, final design and construction support): Hatch, Mississauga, Ont. (lan Ainslie, P.Eng.; Raj Mannem, P.Eng.; Mike Penner, P.Eng.; Rauf Ahmed, P.Eng.; Phil Pantel, P.Eng.; Dave Fuchs, P.Eng.; Don Bodnaruk, C.Tech; Stephanie Gilmour, C.Tech).

Owner: Keeyask Hydropower Limited Partnership.

Other key players: Manitoba Hydro (client), AtkinsRéalis (electrical and mechanical design subconsultant), KGS Group (geotechnical and structural design and construction support), Northern Training and Employment (funding), Canmec Industrial (spillway gates and monorail), COH (powerhouse crane), Voith Hydro (turbine generator), Powell Canada (transformers), Toromont Cat (diesel generation), ABB (motor control centre and excitation transformers), Bentley Systems (software).