IDR Commercial Construction Management (IDR) was tasked with the complex BC Hydro Vault Upgrade at Harbour Centre, a high-rise in the heart of Vancouver’s downtown core. This ambitious project involved installing new underground utilities beneath the 1977-built skyscraper and upgrading BC Hydro’s vault infrastructure with minimal disruption to the building’s operations and the high-traffic area surrounding it. To accomplish this, we partnered with Highwalker Earthworks, who provided precision excavation services that would allow us to install modernized utility infrastructure while preserving the structural integrity of this iconic building
Project Scope and Challenges
Our role in this project required a coordinated approach to create and prepare space for new utility installations within a one-story underground parkade. This included breaking through the concrete flooring and navigating tight, confined spaces beneath the building to reach the required installation depths. Given the high-stakes environment, we entrusted Highwalker with the critical task of safely removing concrete and excavating into the sandstone beneath to create space for our team’s utility work.
This project presented several unique challenges.
Structural Sensitivity
Working directly beneath an operational high-rise required exceptional precision and caution to ensure that every step of the process upheld the safety and stability of the structure. Each excavation phase needed to account for the building’s existing foundation and structural integrity, as even minor disturbances could have significant repercussions for the decades-old tower.
Restricted Access in a High-Traffic Zone
The project’s downtown location and confined work area required careful coordination to minimize disruptions to Harbour Centre’s daily operations. With high pedestrian and vehicle traffic surrounding the site, developing a strategy that prioritized safety and efficiency while still adhering to strict project timelines was essential.
Multiple Excavation Depths
To accommodate the multiple elevations needed for drainage, concrete pit bases, and conduit runs, we developed a highly detailed and intricate excavation and backfilling plan. This plan outlined specific sequences of work for each level of excavation, ensuring precision and efficiency at every stage of the process.
Difficult Soil Conditions
The soil beneath the concrete was predominantly sandstone, a dense and challenging material that called for specialized handling. Standard excavation methods would have been ineffective and could risk destabilizing the surrounding area.
Solutions and Execution
Precision Excavation and Tooling
Highwalker Earthworks brought advanced excavators designed for precision work, ideal for the parkade’s tight quarters. They ensured consistent accuracy with the depths and placements needed for our utility conduits using a Leica laser level.
Our team meticulously planned each move, employing specialized techniques and equipment to minimize vibrations and load shifts, safeguarding Harbour Centre’s structural framework throughout the project.
Jackhammering in Sandstone
Given the sandstone substrate, traditional excavation was impossible, so Highwalker employed high-precision jackhammering using a John Deere 17 P-Tier compact excavator. It allowed us to carefully break through the sandstone layer in measured increments, achieving the necessary depths without compromising safety or structural stability. This method was crucial for preparing safe, durable spaces for the multiple conduit and drainage lines needed in the upgrade.
Backfilling and Compaction in Stages
Once we installed the utilities, Highwalker carefully backfilled the area in multiple stages with a Volvo ECR58, a compact excavator, to access hard-to-reach areas. This process allowed for controlled, layered compaction with a 1000 pound tamper, which is essential for meeting structural and safety standards. Highwalker’s broad selection of equipment and techniques ensured each step of layering the diverse elements could be executed flawlessly.
Parkade Restoration
Our team implemented traffic control measures and coordinated closely with building management to ensure smooth, uninterrupted access for tenants and visitors during the project. Following the utility installation, our teams restored the area to its original function, converting the parkade back to a fully operational space ready for vehicle traffic.
3 Key Takeaways
1. Collaborative Execution
Our partnership with Highwalker highlights the substantial advantages of bringing in specialized excavation expertise to handle the unique challenges of complex urban utility projects. By combining our construction management skills with their excavation experience, we ensured that the project was executed with high accuracy and care, ultimately delivering successful results in a demanding downtown environment.
2. Precision-Focused Solutions
Highwalker’s precision jackhammering solution allowed us to carry out excavation tasks safely and effectively beneath an older active high-rise structure. Their specialized methods allowed our team to achieve the necessary depths within confined spaces while minimizing vibrations and disturbances. This ensured that the structural integrity of the building remained uncompromised throughout the project.
3. Efficient Project Delivery
Our project management strategy and an innovative approach to restricted-access excavation enabled us to execute the project smoothly and efficiently, even within the challenging downtown environment. By carefully coordinating each phase and leveraging specialized techniques suited to tight spaces, we maintained a safe and organized work site while keeping the project on track and within schedule.
Results
The Harbour Centre BC Hydro Vault Upgrade is a testament to our commitment to innovative, solution-oriented construction practices, particularly in challenging urban environments. This project highlights our proactive approach to overcoming complex conditions, including our dedication to collaborating with the best in the business, like the excavation experts at Highwalker Earthworks. By bringing in their specialized expertise, we ensured that the project was executed carefully, reinforcing our dedication to delivering results that protect and enhance essential infrastructure in Vancouver’s bustling urban landscape. Our team’s adaptability and forward-thinking strategies allowed us to meet the project’s unique demands, ultimately supporting the longevity and resilience of a critical utility hub beneath one of the city’s iconic buildings.