In 2024, we partnered with IDR Commercial Construction Management (IDR) on an intricate underground utility upgrade at Vancouver’s Harbour Centre. The high-rise building, opened in 1977, required a BC Hydro vault upgrade to ensure equipment compliance. IDR reached out to us because the project required specialized excavation within the parkade one story underground. During the project, Highwalker was responsible for precision concrete flooring removal and excavation, creating the necessary space for IDR’s utility installations, all while protecting the foundational structure of this iconic building while it was still in use.
Precision Excavation Case Study Summary
Highwalker Earthworks partnered with IDR in 2024 to upgrade a BC Hydro vault at Vancouver’s Harbour Centre. They removed concrete, jackhammered sandstone, and backfilled to install utility conduits, overcoming structural, soil, and access challenges. Using specialized equipment, the project was completed on time, modernizing the utility vault while protecting the building’s integrity.
Excavation Scope and Challenges
At the project’s onset, we were tasked with removing the concrete parkade floor and excavating into the sandstone beneath. This required cutting through concrete and jackhammering the sandstone layers with high precision to achieve the multiple depths necessary for the conduits and drainage lines. It also involved backfilling and compacting in numerous steps to accommodate different conduit runs.
The project posed multiple challenges:
- Structural Preservation: Since we were working directly below a decades-old skyscraper, preserving the stability of the building was paramount.
- Complex Soil Conditions: The subgrade soil consisted mainly of sandstone, which required precise jackhammering rather than standard excavation methods.
- Restricted Access: Harbour Centre’s location and high-traffic surroundings demanded careful planning to avoid disturbances and maintain an efficient work pace.
In densely populated urban areas like Vancouver, shoring also protects adjacent properties and infrastructure. The deeper the excavation, the more critical it becomes to stabilize the surrounding environment, as failure to do so can impact nearby buildings, roads, or utilities.
Solutions and Execution
Our team employed advanced techniques and specialized equipment to address these challenges and support IDR’s project requirements.
- Precision Excavation and Tooling: We ensured precision in confined spaces by meticulously working with an ECR58 Volvo compact excavator and a Leica laser level throughout the excavation process. The laser level guided our team in achieving the exact depths IDR needed to install the conduit runs safely.
- Controlled Jackhammering in Sandstone: Given the sandstone subgrade, we used a John Deere 17 P-Tier compact excavator to complete high-precision jackhammering instead of traditional digging. This approach allowed us to reach the depths necessary for overlapping utility conduits and drainage lines while maintaining structural integrity.
- Backfilling and Compacting in Stages: IDR had to install overlapping conduits and drainage lines, so we performed a staged backfill and compaction throughout the process. We used the Volvo ECR58 to sling material backfill in the hard-to-reach areas and once that was complete we made multiple passes with a 1000 pound tamper to pack the material.
Results
Working with IDR, we successfully completed the BC Hydro vault upgrade at Harbour Centre within the project timeline. Our advanced excavation techniques and experience enabled IDR to carry out the utility installation smoothly, modernizing the utility vault beneath a Vancouver landmark without disrupting its structural integrity.
Key Takeaways
- Effective Collaboration: Highwalker Earthworks and IDR’s teamwork showcased the value of combining excavation expertise with construction management for complex utility installations.
- Precision-Focused Execution: Leveraging specialty equipment and precision jackhammering allowed for high accuracy and minimized impact on the building’s foundation.
- Urban Excavation Success: Despite challenging downtown conditions, our well-planned excavation methods and innovative solutions led to a streamlined, safe project outcome.
This project highlights Highwalker Earthworks’ capability to perform specialized excavation under difficult conditions, delivering results that respect and protect Vancouver’s urban infrastructure.