Kapuni Weir in New Zealand had been showing clear signs of erosion around the weir base and flanking banks. Left unmanaged, the ongoing scour posed a growing risk to the stability of the structure. Bluemont Rock Bags™ were brought in to address the problem and protect the weir from further deterioration.
Project Snapshot
Location: Kapuni Weir, New Zealand
Client: Downer NZ
Application: Weir scour and erosion protection
Rock Bags Installed: 2t Eco-Green Bluemont Rock Bags™
Project Overview
Kapuni Weir is a river control structure with constant water movement passing over and around it. That steady flow gradually wears away at the base and surrounding banks. Where no protection exists, that deterioration can quietly become a serious structural issue.
The Challenge
The weir base and adjacent banks had been eroding steadily under the pressure of the water flow. Over time, this risked undermining the weir and destabilising the riverbank beside it. What was needed was a weir erosion control solution that could perform reliably in a live waterway while fitting around the irregular contours of the weir and banks.
The Solution
Bluemont Rock Bags™, also known as Kyowa Filter Units, were chosen for their capacity to conform to uneven surfaces and hold their position under sustained water flow. They offer a flexible, long-lasting approach to erosion control that suits the demanding conditions found at weir structures.
Results
The installed rock bags stabilised the eroded areas around Kapuni Weir, shielding the toe and flanks from ongoing scour and reducing the likelihood of structural damage. The units sat well against the natural contours of the site, delivering solid protection without requiring significant civil construction. It proved to be a straightforward, practical solution for the client in an active river setting.
Related Applications
Bluemont Rock Bags™ are ideal for a broad range of erosion and scour protection work – including weir and dam toe protection, riverbank stabilisation, bridge scour protection, and erosion control wherever high-flow conditions are present.
Have a challenging erosion or scour issue? Talk to our team about practical solutions designed for long-term infrastructure protection. Contact us at info@rockbags.nz or call +64 9 872 2622. For Australia-based projects, email info@rockbags.com.au.
