Project Start Year: 2027
The Invercargill and Ōreti Flood Resilience Project strengthens key sections of the flood infrastructure network across the lower Ōreti rural floodplain and Waihōpai Invercargill’s urban flood network.
In the Ōreti catchment, works restore and strengthen rural stop banks affected by settlement, erosion, vegetation and structural defects, alongside targeted channel improvements where modelling has identified performance constraints across the wider floodplain. In Invercargill, the project addresses low sections of the Ōtepuni stop bank within the city’s urban flood network, aligning performance with recent upgrades to the Waihōpai River stop bank. Works may include rock armouring, vegetation management and drainage improvements, supported by updated 2D hydraulic modelling to guide staging and prioritisation.
Benefits
These works reduce flood impacts on homes, productive land, transport links and critical infrastructure across the lower Ōreti catchment and Waihōpai Invercargill. Strengthening weak points improves the reliability of the wider flood infrastructure network during high flows and storm events. Acting early helps limit disruption, reduce recovery costs and support long-term community confidence.
Adaptation
Invercargill sits at the confluence of the Ōreti, Waihōpai and Ōtepuni systems, where river flows and downstream water levels interact across rural floodplain and urban networks. Updated 2D hydraulic modelling has helped assess how these systems perform together, identifying low points and performance gaps. This project responds by staging investment across both rural and urban areas to improve alignment and support longer-term adaptation planning.
Resilience
By improving consistency across rural and urban sections of the flood infrastructure network, the project reduces the risk of isolated weak points undermining wider system performance. Aligning standards between the Ōreti floodplain and Invercargill’s urban network supports more predictable behaviour during high flows and improves the region’s ability to respond and recover when events occur.
Collaboration
Co-funded through the Regional Infrastructure Fund and Environment Southland.
Environment Southland leads delivery, with ongoing coordination and engagement with Southland District Council, Invercargill City Council and Te Ao Mārama Inc. on behalf of Ngāi Tahu ki Murihiku.
Ongoing engagement with rural landowners, infrastructure partners and agencies such as NZTA where works interface with transport corridors.
This coordinated approach supports consistent standards across rural and urban networks and strengthens long-term relationships that underpin effective flood risk reduction.
This project builds on earlier co-funded work and positions the region for future, catchment-wide investment informed by updated modelling and evolving risk.
Find out more here: Waihōpai Invercargill infrastructure upgrade - Environment Southland