Blacks Beach Revetment
In October 2024 we completed the Blacks Beach Revetment—a critical project involving the construction of a 110m-long armour rock wall designed to protect the main access road serving the Mahia Peninsula. This main artery was highly vulnerable to coastal erosion and storm damage, making the need for a definitive, robust solution urgent.
As Principal Contractors for this contract, our role spanned from methodology planning to final delivery, requiring us to manage all aspects of the complex project delivery.
Extreme Logistics Demand Coordination
This job presented significant logistical hurdles that tested our project management capabilities:
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Materials Challenge: The rock specifications were demanding, requiring 3,300 tonnes of specialised armour rock to be delivered from a quarry in Rotorua.
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Site Constraint: Due to extremely limited storage space on site, the rock delivery schedule required precise, just-in-time coordination with the revetment's daily progress.
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Environmental Constraints: Work was severely restricted by tides, swell, and persistent bad weather (including a state of emergency due to flooding). We were forced to plan and execute rock placement around low tides to maintain safety and efficacy.
The Pryde Solution: Precision & Productivity
To manage these constraints and deliver the project on time and within budget, we implemented a strategy focused on rigorous planning and technical precision:
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Optimized Scheduling: We carefully planned high-productivity rock placement during low-tide windows, dedicating high-tide periods to other essential activities (e.g., material preparation, logistics checks) to ensure overall productivity remained high.
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Principal Management: We effectively managed all project components, utilising subcontractors for specialised services including traffic management, rock transport, material testing, surveying, and final guard-rail installation.
Millimetre Accuracy Under Duress
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The construction of the armour wall required absolute adherence to the geotechnical design to guarantee long-term performance:
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3D Grade Assist: Our Caterpillar 323 excavator, equipped with 3D grade assist capabilities, was the key piece of machinery for execution.
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Precision Placement: This technology was crucial for ensuring the wall’s output matched the design exactly, allowing us to construct the batter face and general revetment shape to the correct size, gradient, and height.
The Outcome
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Despite the challenging logistics—coordinating a massive off-site rock delivery and working under severe time and weather restrictions—Pryde Contracting successfully delivered the Blacks Beach Revetment on time and within budget. The 110m armour rock wall now provides robust, permanent protection for the Mahia's vital access road.
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Client: Wairoa District Council