Taranaki Street pump station and rising main

Wellington Water set out to renew, upgrade and reconfigure a key portion of Wellington’s CBD wastewater network. Their key focus was to reduce the risk of failures, prevent harbour contamination, increase network flexibility and support future growth—all while delivering resilient infrastructure for the community with minimal disruption.

This work was essential due to the aging network, with some cast iron rising mains over 100 years old beginning to fail. The existing rising mains on Kent Terrace and Victoria Street were also isolated from the rest of the network, limiting flexibility during failures. Additionally, the system lacked the capacity to accommodate future growth, and frequent failures had led to negative publicity, with pollution affecting both the CBD and the harbour.

A new pump station on Taranaki Street was designed to alleviate the pressure on the existing network and provide a new connector to the main interceptor, while also linking up the wider network.

Our team provided support across multiple disciplines, including Masterplanning, Design, Construction Monitoring and Project Management, with input from our Water, Structural, Geotech, Environmental, Planning, and Fire teams. Our approach involved mobilising a dedicated team to deliver this project.

We managed the entire service delivery from start to finish, including installation of a new underground pump station and rising main wastewater pipe - now fully integrated into the existing system. This new infrastructure eases pressure on the network and adds redundancy, so if the current system ever fails, flows can be redirected. Designed to last 100 years, it also factors in seismic resilience and future population growth.

Key features of the project included:

• A secant piled pump station with site-specific seismic design for a L3 structure
• Overcoming construction challenges in a constrained CBD location with reclaimed ground and high groundwater conditions
• Navigating extensive, congested historical services and areas of archaeological significance 

We're proud to have helped to rebuild Wellington’s wastewater infrastructure and ensure cleaner harbours for the future.

The outcome of the project not only strengthens Wellington’s wastewater infrastructure, but also contributes to the long-term environmental, social and economic well-being of the CBD and surrounding areas. It’s a significant step to more resilient wastewater infrastructure in the city.