Manitoba Hydro is the primary provider of electricity and natural gas in Manitoba, operating one of the cleanest energy grids in North America. In Manitoba’s Interlake Region is a regional hub called the Ashern Generation Station. This facility plays an important role in maintaining services to ensure reliable power distribution throughout the area to support surrounding businesses, homes and local industries like fishing, agriculture and recreation.
In the spring of 2023, GeoStabilization International, a geohazard mitigation firm in North America, was brought in to support critical infrastructure upgrades to address concerns around foundation and containment issues. The project included environmental impacts, safety, space constraints, ground conditions and the need to maintain operations throughout construction.
Sustainable solutions
Micropiles offered the best solution for the geotechnical and logistical challenges on-site as they can be installed with compact equipment in tight spaces, making them ideal for this congested work zone. Within the utility’s 230-kilovolt switchyard, the team installed 43 micropiles with steel caps to support new structures including a new blast wall, foundations and containment systems. These upgrades also provided protection for personnel and equipment, and prepared the site to handle future operational demands. Working within the energized substation, the crew executed technically complex work, while adhering to strict safety protocols and minimizing operational disruptions.
Mitigating challenges in design and installation
To address subsurface instability and weak and variable layers of soil, GeoStabilization needed to provide deeper foundational support for new concrete structures, the wall and an oil containment pit. Shallow foundations could settle unevenly or fail over time. Micropiles were drilled up to 25 feet deep, utilizing eight 0.625-inch permanent casings plunged into bedrock. Inside each casing, No. 8 threadbar was installed and encapsulated in a neat grout mixture to achieve the required structural capacity. There were also groundwater concerns to address. GeoStabilization used pressure grouting in areas with standing or flowing water to maintain pile integrity. Customized casing splice details were developed to meet Manitoba Hydro’s specifications, and centralizers were installed every 10 feet to ensure accurate threadbar alignment.
The project also required careful drilling sequencing to prevent destabilization of surrounding soils and structures. The team implemented a staggered drilling pattern, spacing out active locations to minimize ground vibrations and maintain stability. This approach protected existing equipment and nearby foundations while allowing steady progress across multiple work fronts.
Specialized equipment for limited access conditions
Because the area only had a 14-foot overhead clearance and very little space to move, the GeoStabilization team used compact drilling equipment designed for small spaces. A compact casing drill, Dodge 5500 truck, water buffalo trailer, and colloidal shear grout mixer allowed the crew to work safely and efficiently without disrupting operations. To make sure the piles met all quality standards, the team followed strict testing protocols, including grout testing to confirm a 28-day compressive strength of 30 MPa, pile proof loading and field inspections conducted with Manitoba Hydro staff.
After installing the micropiles, steel pile caps were attached using pre-cut galvanized plates and anchor rods. Hydrovac equipment was used to carefully expose the piles before welding, which helped ensure accurate placement and strong connections.
Project collaboration and scope expansion
Throughout the project, the GeoStabilization team worked closely with Manitoba Hydro and other contractors. This included daily co-ordination meetings for alignment and efficiency where integrated teams could issue requests for information and field instructions. The teams also held joint tailgate safety meetings and strictly adhered to Manitoba Hydro’s safety protocols, conducting daily hazard assessments, personal protective equipment checks and site-specific orientations for all personnel.
After the initial project was complete, Manitoba Hydro requested additional work to further advance station stability. GeoStabilization installed 16 additional micropiles in a nearby substation area. Work included adjusting manpower, equipment schedules and material procurement without impacting the original timeline or budget.
To make sure the piles met all quality standards, the team followed strict testing protocols, including grout testing to confirm a 28-day compressive strength of 30 MPa, pile proof loading and field inspections conducted with Manitoba Hydro staff.
Project outcomes
The Ashern Generation Station micropile project was completed on schedule and within budget, while working with a variety of project considerations and site constraints. Working within an energized substation reinforced the importance of thorough pre-construction risk assessments and flexible equipment strategies.
The team’s ability to adapt to complex geotechnical conditions and to deliver strong results helped Manitoba Hydro strengthen and expand infrastructure. And the specialized micropile solutions offer a reliable and efficient option for upgrading substations. These improvements support the businesses, homes and industries that rely on uninterrupted services throughout Manitoba’s Interlake Region.