Customer: Auckland Council Healthy Waters
Contract: Construct Only
Location: Downtown, Ports of Auckland
The Ports of Auckland Outfall Upgrade Project, funded by the Auckland Unitary Plan, has been in Auckland Council’s pipeline for a number of years. And we are pleased to be constructing this important infrastructure for downtown Auckland.
The proposed design is an inverted siphon (U-bend shaped pipe). The horizontal section is 2.5m in diameter and approximately 270m long, installed within bedrock to avoid risks associated with construction within reclaimed land. This horizontal section connects two shafts, the inlet shaft south of Quay Street and the outlet shaft in the Ports of Auckland site that connects to a marine outfall.
Once complete, the new outfall will increase the stormwater network’s capacity and improve the resilience of downtown Auckland’s infrastructure. The improved network will also mitigate flood risk for properties in the downtown area, including Britomart train station.
This stormwater outfall upgrade draws on McConnell Dowell’s extensive track record in marine outfall construction using trenchless methodologies.
Work on this project includes:
- Service relocation works
- Piling works for both the outlet and inlet shafts
- Excavation works for both shafts
- Tunnelling under Quay Street to a maximum depth of 20 metres
- Chamber and outfall construction
- Culvert strengthening
This project is expected to be completed in late 2023.