Large Woody Debris Extraction
Rata Forest Management Ltd Improvements to the land resulting from Large Woody Debris Extraction include enhanced water quality, increased sediment retention, and the creation of biodiversity that benefits the land and aquatic species.
- Large Wood Debris Extraction
Te Arai Extraction
Challenge
Large woody debris (LWD) mobilized during Cyclone Gabrielle deposited along the Te Arai River flood terraces and stream banks pose a serious threat to the safety of residents, infrastructure, and the city's main water supply.
Solution
The project tackled this challenge first by locating the LWD material for removal using remote sensing technology and using forest engineering formula to calculate for volume. We then developed a comprehensive extraction plan and cost model. The project crossed over 60 landowner titles which required communication and collaboration to ensure an efficient and safe removal operation without compromising the landowner’s income earning ability for their varied landuses. Iwi participation and support was fundamental to the success of the project, the Te Arai River being the sacred awa for Rongowhakaata, the river passing three of their marae. Rata employed a harvest line extraction system to extract the LWD with the least environmental footprint. The extracted LWD material was burnt with Rata’s high oxygen burn unit.
Impact
By removing the LWD, the project significantly reduces flood risk and damage resulting from LWD mobilization, safeguarding the community and Gisborne infrastructure assets. It also created employment opportunities within the local area, contributing to the economic well-being of residents and tangata whenua. Furthermore, the project created an opportunity for the community to plan the environmental restoration of the riparian ecosystems, ultimately strengthening community and empowering the community to develop their own sustainable future-planning model.
