Celebrating completion of a major flood recovery project
Environment Canterbury media release: 25th September 2024
Three years after the May 2021 floods, we've completed a significant programme of work to restore Canterbury's resilience to extreme weather events.
“This was the first red weather warning we’d had in Canterbury,” said Shaun McCracken, regional lead river engineering, who supported the initial emergency response and oversaw the works as flood recovery manager.
Initial emergency response and scope of damage
“The forecast was for around 300mm of rain in 24hrs, and what we ended up getting was 500mm of rain over 48hrs, spread everywhere from Waimakariri to Mackenzie.”
The extreme rainfall caused widespread flooding and prompted a region-wide state of emergency. The floods caused extensive damage to homes and businesses, as well as critical infrastructure including stopbanks, riverbanks, and flood protection vegetation.
“Initially we focused on damage reconnaissance, identifying damaged infrastructure across the region so we could prioritise and design repairs for each site,” Shaun said.
“While our scope was to restore the resilience that existed before, on some sites we were able to mitigate the increasing challenges posed by climate change. This includes the room for rivers concept, which reduces pressure on flood protection assets and provides for a healthier waterway.”
Project execution and achievements
The project focused on more than 400 individual repair jobs across the region, including repairs to more than 5kms of stopbanks and planting more than 60,000 native and exotic trees.
“In many cases, we were using existing vegetation that was still standing or that had washed out in the flood. We were able to drag it back in while it was still alive and replant it, turning a liability into an asset.
“The other big part of work was erosion and scour protection. In some of the more constrained areas, such as through Geraldine township, we used rock protection to protect riverbanks from erosion.”
While the project is complete, some sites remain vulnerable and continue to be monitored closely particularly while new vegetation becomes established. Recent flood events have tested these areas, providing valuable information for ongoing improvements.
Community impact and future preparedness
Councillor Ian Mackenzie is the lead for Community Preparedness and Response to Hazards. He said completion of the project marks a significant milestone in building future resilience for the safety of our communities.
“This achievement not only protects our residents but also ensures the long-term sustainability of our infrastructure. We're proud of the collaborative effort that has gone into this project and remain committed to serving our communities by continually improving our preparedness for environmental challenges."
Mark Faichnie, area supervisor – central, worked on the project from emergency response flood patrol to the reinstating of damaged sites across Ashburton. “It was an amazing sense of achievement, to have delivered all that work. I hope it provides landowners and farmers some security and reassurance.”
The National Emergency Management Agency (NEMA) co-funded approximately $8.3 million of the total cost of $22.6 million, through a one-off emergency fund.