Fire and Emergency New Zealand has released its investigation into the Christchurch Port Hills fire, which burned 650 hectares and took three weeks to bring under control.

The cause of the fire remains undetermined.

The blaze started near Worsleys Road just after 2pm on February 14th 2024, and quickly spread, threatening multiple properties and forcing evacuations. A state of emergency was declared by both Christchurch City and Selwyn District Councils as emergency services worked to contain the fire. Firefighters from over 45 brigades, along with aerial support and ground machinery, were deployed.

A residential structure was destroyed, and parts of the Christchurch Adventure Park sustained damage.

Specialist fire investigators conducted a comprehensive review, pinpointing a five-square-metre origin site about 50 metres off Worsleys Road. However, despite interviewing three witnesses, reviewing publicly submitted photos and CCTV footage, and eliminating all possible ignition sources, no definitive cause could be identified.

The property owner where the fire started told investigators there had been no activity or equipment in use that day. As a result, the fire has been classified as undetermined, though officials say they will reopen the case if new information comes to light.

Fire and Emergency said Canterbury’s warm, dry summer and dry vegetation played a significant role in the fire’s rapid spread.

An operational review into the response effort found that the quick and heavy deployment of resources in the early stages helped contain the fire. Overnight ground operations and increased aerial support on day two played a key role in controlling the blaze.

Lessons learned from the 2017 Port Hills fire, including better community preparedness, inter-agency coordination, and public communication, were credited with improving the response this time.

Fire and Emergency said it remains committed to continuous improvement in wildfire management, especially in high-risk areas like the Port Hills.