Greville Road Stormwater Culvert Upgrade

The Alta team used our extensive construction experience to provide ACHW with constructability advice on this water infrastructure project.

Project scope

During Auckland’s 2023 Anniversary Weekend flooding event, a culvert under Greville Road failed, resulting in severe flooding.  The 1950mm diameter culvert failed near the inlet on the northern side and required replacement.

This project involved significant upgrades to existing stormwater infrastructure. A key component was the installation of a new 2,100mm internal diameter stormwater pipeline, achieved using a Micro-Tunnel Boring Machine (MTBM). The tunnelling was carried out in two separate drives, one extending 220 meters and the other 50 meters. To support this process, three temporary shafts were constructed, allowing access points for the MTBM during installation.

Following the successful installation of the new pipeline, the existing ARMCO culvert was decommissioned. In addition, two in-situ manhole chambers were built at points where the pipeline changes direction. These chambers not only help facilitate smoother transitions within the network but also enhance the system’s stormwater capacity, particularly during periods of heavy rainfall.

Alta’s work

Alta served as Engineer to Contract and Engineer’s Representative on this Healthy Waters project. We provided constructability and cost estimation advice throughout the design phase of the project.

Key learnings

Our team developed a deeper understanding of managing works within a closed landfill in a flood-prone area.  We learnt how to safely decommission a large-diameter culvert. We contributed to the design development in a model similar to an Early Contractor Involvement (ECI).

Alta’s project team

Rory Bishop (Engineer to the Contract) and Craig Scott (Engineer’s Representative).