Arch Engineers undertook a complex excavation project in the south valley, involving two deep box cuts ranging from 30 to 40 meters in length—an effort that pushed the limits of deep excavation in the south valley region. Each featured narrow 7000mm headwalls and movable struts designed to allow equipment insertion and removal. The excavation posed major challenges due to 8000mm-deep headwalls and unstable, sandy pebble soils starting at 3250mm depth.
Groundwater appeared about 4000mm below construction grade, complicating the project and demanding robust water management. Engineers excavated two deep pits on either side of a creek. Unstable soil caused lateral pressures, threatening excavation stability. High groundwater added complexity, requiring careful dewatering strategies.
The team engineered narrow headwalls and movable struts to maintain lateral support while enabling equipment access—even on short notice. These struts offered both strength and flexibility.
Arch Engineers developed an adjustable strut system that responded to varying loads and soil conditions. The design allowed real-time modifications to suit excavation demands.
Given the sensitive creekside location, the project required strict adherence to environmental regulations. Arch Engineers planned meticulously and collaborated with provincial and federal regulators. Their efforts minimized ecological impact and ensured compliance throughout construction in the south valley, where deep excavation in a protected valley demanded precision and care.