After Cyclone Gabrielle caused significant damage to the already narrow Kaiikanui Road, ICB rapidly mobilised to stabilise a steep slope at risk of further collapse. By using a soil nail and mesh system, ICB preserved road access for local and coastal communities—without the need for full road closures or large-scale earthworks.
Quick Facts
45 soil nails, each 5 metres long, installed at 2-metre spacing
High-tensile steel mesh pinned to the slope to prevent erosion
Safety rails and give-way signage installed to improve safety
Slope stabilisation completed in a matter of weeks
LOCATION
Kaiikanui Road, Opuawhanga
CUSTOMER
Whangarei District Council
SERVICES
Soil Nails & Steel Mesh
The Challenge
In the wake of Cyclone Gabrielle in early 2023, a section of Kaiikanui Road slipped away, severely narrowing an already constrained route. The site featured steep topography, very limited access, and urgent time pressures—especially as the alternative route serving the region was also geotechnically compromised. Maintaining safe, continuous access for the local community was critical.
A traditional retaining wall would have required full road closure, large machinery, and up to six months of work—delays the area couldn’t afford. Instead, the team needed a practical, lower-impact solution that could be installed rapidly and safely, despite the risk of further slope failure.
The Solution
Soil nails were chosen as the most efficient and cost-effective approach. Each nail was five metres long, with the final two metres anchored into virgin greywacke rock for solid resistance. ICB used a wagon wheel-mounted drill rig—allowing safe, lightweight operations without overloading the slope.
The solution included:
Drilling and anchoring 45 soil nails
Installing high-tensile wire mesh across the slope face
Adding safety rails and give-way signage for single-lane operation
This approach significantly reduced construction time, avoided major disruption, and minimised cost and environmental impact.
The Impact & Results
The project successfully stabilised the slope, safeguarded public access, and enhanced safety for all road users. Despite difficult access and high-risk conditions, ICB delivered a robust result ahead of schedule. The road remains open and resilient against future weather events, ensuring continued access for remote communities—exactly as the project intended.
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