Performance of bioengineering solutions (poplars and willows) for riverbank protection during Cyclone Gabrielle
Posted on July 08, 2026
Bioengineering solutions (trees – primarily poplar and willow cultivars) have been used to manage flood risk and erosion throughout NZ for decades and continue to be used as a cost effective and highly functional part of river management.
This project looked at how bioengineering functioned within Hawke’s Bay and Tairāwhiti, including performance in relation to flood flow effects, erosion control, stopbank protection, interception of silt and woody debris, and benefits to downstream receiving environments.
Studying the effectiveness of different techniques, tree species, management, relative location, and age of trees were significant parts of the project.
The conclusions derived will inform best-practice for river managers, to ensure bioengineering techniques are implemented and managed for optimal performance of river control schemes during flood events, and to minimise the downstream effects of flooding, sediment, and woody debris.