Every year, Auckland's stormwater network intercepts thousands of tonnes of sediment, litter and debris that must be removed to keep the network functioning effectively.
InterGroup's Resource Recovery Facility is transforming catchpit waste and road sweepings into recovered resources, supporting Auckland Council's circular economy objectives.
Thousands of tonnes of material previously destined for landfill have instead been recovered for beneficial reuse through the partnership between Auckland Council Healthy Waters and InterGroup's Resource Recovery Facility.
InterGroup has been supporting Auckland Council’s catchpit maintenance programme since 2020, helping maintain Auckland’s stormwater network by removing sediment, litter and debris from across the region. Each year, InterGroup completes approximately 180,000 catchpit servicing visits on behalf of Auckland Council, with around 92,000 catchpits serviced twice annually. Material collected through this work is processed through InterGroup’s Resource Recovery Facility for recovery and beneficial reuse wherever possible. The purpose-built facility, operational since late 2024, has enabled a significant proportion of material collected from Auckland’s stormwater network to be recovered and diverted from landfill, supporting Auckland Council’s sustainability and circular economy objectives.
Healthy Waters and Flood Resilience Head of Operations, Andrew Skelton says this is a great example of how effective infrastructure maintenance can deliver wider benefits for Auckland.
“The work our contractors do every day helps reduce the risk of flooding for communities, and through resource recovery we're also reducing waste and supporting a more circular approach to managing the material removed from our stormwater network”, he says.
Delivering environmental outcomes
Rather than sending this material directly to landfill, InterGroup processes it through its purpose-built East Tamaki Resource Recovery Facility where valuable materials are separated and recovered for beneficial reuse wherever possible.
Resource recovery milestones
Through its resource recovery process, InterGroup recovers valuable resources from catchpit material that would otherwise be sent to landfill. Water is treated and reused within the Resource Recovery Facility, while recovered sand and aggregates are washed, graded and separated into reusable products, including sand, 9.5 –19mm chip and 25mm drainage stone. These materials are then supplied for beneficial reuse across the civil construction, drainage and infrastructure sectors, reducing reliance on virgin quarried materials and supporting a more circular approach to resource management.
Supporting Auckland's circular economy
The recovery process reduces landfill demand while recovering reusable materials, reducing transport impacts and helping maximise the value extracted from municipal waste streams. By recovering valuable materials from what was previously treated as waste, the facility reduces landfill demand, supports more efficient use of natural resources and demonstrates how infrastructure maintenance can contribute to New Zealand's transition towards a circular economy.
“Investing in this type of solution is not only a smart environmental decision but a good commercial one,” says Sam Clive, General Manager Customer and Commercial at InterGroup.
“We’re recovering valuable materials from Auckland’s stormwater network that would otherwise have gone to landfill, while reducing our own operational costs. It’s a total win-win for the environment and for Auckland.”
This demonstrates how specialist infrastructure maintenance can deliver broader environmental benefits beyond maintaining essential public assets.