- Damian Young
- 12 minutes ago
- 2 min read
In the summer of 2024, the Zealandia team walked over 20 km of Te Ārai River with a 360° camera in hand - and a mission in mind. Working with Te Ārai Community Catchment Group and Gisborne District Council /Te Kaunihera o Te Tairāwhiti, we combined immersive video, spatial data, and boots-on-the-ground observations to create a Virtual StreamWalker - a digital twin of the river.
At its heart, the Willow Management Plan is about providing tools to enable river management so that it can breathe and move naturally again. And thanks to data-driven mapping and spatial analysis, we're helping ensure the future of the awa is stable, diverse, and resilient.
Why? Because although willows and poplars were originally introduced to stabilise riverbanks, decades of unchecked growth have significantly altered the river’s morphology. In-channel regrowth, reduced flow conveyance, and dense stands of willows have led to bed scouring, bank erosion, and diminished aquatic habitat.
To better assess these impacts in detail, Zealandia conducted a two-day StreamWalk survey covering more than 20 km of river. Using a 360° InstaX4 camera and spatially linked audio recording, the team captured over 200 geo-referenced videos, forming the foundation of Te Ārai Virtual StreamWalker — an interactive digital twin that integrates high-resolution visuals with GIS data.
Our work turned 200+ videos into a clear, zone-specific action plan that blends traditional river care with modern tech. The plan proposes strategic interventions - from removing dense in-channel willows to planting natives and hydroseeding unstable zones - all tailored to each site's conditions.
This digital environment enables a detailed classification of willow types, densities, and locations, alongside observations of algal growth, woody debris, and legacy infrastructure. Each reach of the river was assessed individually and assigned to one of several management zones based on function and risk:
Conveyance Zones: Targeted willow removal to restore hydraulic capacity
Stability Zones: Root retention combined with native planting
Pinch Points: Management to reduce channel constriction
Spill-out Zones: Encouragement of wetland and successional processes
Deposition-Prone Areas: Rapid stabilisation through hydroseeding and planting
Site-by-site action plans were developed for 47 discrete reaches, enabling collaboration across multiple landowners and interest. These include specific control methods, revegetation strategies, and, where needed, engineering treatments such as riprap. The entire framework is linked into ArcGIS, enabling live tracking, contractor coordination, and adaptive management by Council staff.
Collectively, Te Ārai Virtual StreamWalker and Willow Management Plan showcases the power of combining local knowledge, spatial planning, and immersive digital tools. It offers a scalable model for other catchments in Gisborne, Hawke’s Bay and elsewhere; where the challenge of balancing ecological restoration with land use pressures is both urgent and ongoing.
For smarter, place-based river management, explore Te Ārai Virtual StreamWalker and get in touch so we can go on the journey together (Contact).
Comments