Abstract

Auckland is the largest urban area of New Zealand’s North Island with a population of ~1.7M. Auckland has a sub-tropical climate, with warm and humid summers which can be associated with intense rainfall. January 2023 was Auckland’s wettest month since records began. The heaviest rainfall produced widespread flooding across Auckland on Friday 27 January described as at least a 1-in-200-year event. Two weeks later Cyclone Gabrielle hit Auckland. West Auckland recorded 248 mm of rain.
Tragically these events resulted in six deaths in Auckland, three of which occurred when landslides hit buildings. Two volunteer firefighters lost their lives while undertaking search and rescue operations, and tens of thousands of landslides were triggered.
This paper describes the storm events, the landslides they triggered, and the emergency response work undertaken by engineering geologists and geotechnical engineers.