Built for Selwyn’s growth: Ellesmere Pipeline complete
Selwyn District Council media release: 5th August 2025
The Ellesmere wastewater pipeline to the Pines Wastewater Treatment Plant (WWTP) in Rolleston has been completed four months ahead of schedule and is $9 million under its original $35.6m budget.
The landmark wastewater infrastructure project from the new Ellesmere Pump Station in Leeston to Rolleston is the largest single capital works project in the history of the Selwyn District Council and will support the rapid development and population growth in the Ellesmere region.
The project made significant savings through effective management of the groundwater risks along the construction route, says Council Executive Director Infrastructure and Property Tim Mason.
It also included an ingenious bit of engineering through the largest “live tap” cut-in (cutting into the existing pipe while it’s still in operation) ever carried out in New Zealand – which allowed the system to keep running, reducing costs and disruption and adding environmental benefits from not having to use trucks to move waste while the work was being carried out.
“Our team was incredibly proud of that bit of work, but also at the quality and the speed of the overall project, since we started last July,” Mr Mason says.
Waikirkiri Selwyn Mayor Sam Broughton says that the Ellesmere-Pines wastewater project is one of the most important infrastructure projects the Council has undertaken. “Our Council is focused on making sure we’ve got the right infrastructure in place for our community, both for now and for the future.
“With over 80% of our budget dedicated to roading and water services, we are pleased to see this significant project wrapped up ahead of schedule – and saving money for our community by managing groundwater risks well along the way.”
Ellesmere Councillor Shane Epiha says the project is a great example of the Council delivering long-term benefits for the Selwyn community.
“The timeliness and savings on what was the largest capital project for the council has exceeded all expectations. It’s an example of what partnership, planning, and good decision making looks like. Leaving an incredible asset for the generations to come.”
CORDE General Manager of Construction Andrew Loader says, “We’re proud of the team and their mahi in delivering a complex project that strengthens Selwyn’s infrastructure resilience. Careful planning and coordination across all phases helped minimise disruption as much as possible, while achieving a strong outcome for the district.”
The project includes a new pump station at Ellesmere Sewerage Treatment Plant in Leeston, a new suction intake pipe from the Ellesmere wastewater ponds and a new pump station at Upper Selwyn Huts.
The project installed 18km of 355mm diameter pipe and 7km of 125mm diameter pipe to carry the wastewater from these pump stations to the Pines WWTP.
The work was carried out by main contractor CORDE with design by consultant Beca.