Date/Time
Date(s) - Wed 7 October
11:00 - 12:00
The East Coast Flood Resilience (ECFR) Project was established following damaging flood events across Tairāwhiti, culminating in the widespread impacts of Cyclone Gabrielle in 2023. It integrates geomorphology, flood modelling, engineering, planning, and community engagement to better understand flood risk across East Coast catchments and strengthen the resilience of communities, infrastructure, and culturally significant places.
A key finding is that flood risk is influenced by more than water levels. Tairāwhiti’s steep, erosion-prone terrain, weak sedimentary geology, and high sediment loads mean extreme rainfall can significantly alter channels and floodplains. Geomorphic Change Detection (GCD), landslide and gully mapping, and sediment connectivity assessments show that post-storm changes can modify channel capacity, flood pathways, and inundation patterns. This highlights the need to incorporate geomorphic processes into flood modelling rather than relying on static river representations.
By integrating sediment dynamics, channel evolution, aggradation, and catchment-scale processes with hydraulic modelling, the ECFR Project supports more informed long-term resilience planning. Collaboration with mana whenua, communities, and partner organisations ensures scientific evidence is combined with local knowledge and values. Its lessons provide a valuable framework for improving flood resilience in dynamic river systems across New Zealand.
Presenter: Dr Lenka Ondrackova – Fluvial Geomorphologist at Gisborne District Council