Two years since the first 2023 severe flooding event in Auckland, 80% of the more than 800 road slips across the region have been repaired and AT’s flood recovery programme is ahead of schedule.
More than 2000 slips were reported to AT during three extreme weather events; The Auckland Anniversary Weekend Floods, Cyclone Gabrielle and February thunderstorms. The storms wreaked havoc on the Auckland Transport Network, causing major damage to roads (through slips, dropouts, pavement damage etc), bridges, culverts, footpaths, bus stops, transport stations, streetlights, Public Information Displays, wharves and 29 cycleways.
AT’s established contractors - Downer, Fulton Hogan, Ventia and Liveable Streets – swung into action with more than 550 people on the ground per day in those first few months. They restored access for residents to more than 130 roads, removed 3,000 damaged or abandoned vehicles from the roading network and 40-60 tonnes (four large barge loads) of debris from Auckland harbours.
1200 smaller slips were fixed fairly quickly. But the more than 800 bigger slips have required extensive investigation to inform sustainable and resilient engineering designs before any construction repair works could begin.
We’re talking about some very big and tricky infrastructure repairs like how to repair the road falling away on both sides of the Glenvar Road ridgetop with a powerline down, 15 large slips on Ahuroa Road which cut vehicular access to Puhoi, 13 slips along a 20km stretch of Scenic Drive and Waitakere, and another 40 slips on both roads to Karekare Beach.
In South Auckland a major slip took out the road to Awhitu Peninsula, while in Tahekeroa a land slip measuring 350m inundated the road and railway line. In Coatesville, the Mill Flat Bridge was washed away – a temporary Bayley Bridge was installed within a week and it’s taken this long to design a permanent solution for a sensitive area that’s safe and affordable.
To date around $270 million has been spent repairing 639 serious slips. There’s still some way to go, but AT is on track to substantially complete the recovery programme this year.
It's been a massive job, with a big price-tag.
The AT Flood Recovery Programme is estimated to cost $390 million, jointly funded by the Crown and Auckland Council: NZ Transport Agency Waka Kotahi ($199m), Auckland Council ($81m) and Crown Infrastructure Partners, now National Infrastructure Funding and Financing ($110m).
“We expected this recovery programme to take two to three years and we’re six months ahead of schedule” said Allan Wallace, GM Road Asset Maintenance & Renewals at AT. “That’s largely due to a dedicated team of engineers, designers, project managers and site crews who’ve worked long hours through all weathers to repair our local roads and restore access for communities. It’s been a long slog, but they’re committed to getting the job done, and after two years I take my hat off to them.”
Mr Wallace says we’re ‘almost there’ with a caveat – in some areas of Auckland the repairs have gone gangbusters, while in others there’s still a way to go.
“Some of the very complex slips are in difficult terrain and on roads where the damage has occurred in multiple places, impacting community access and taking a long time to fix.”
In North Rodney about 98% of the large slip repairs are done, but in West Auckland it’s taking a bit longer. Many of the slips happened on long stretches of roads, or roads that are close to each other, which logistically is tricky when it comes to making sure people can safely get around while multiple construction sites are operating.
Moir Hill Road Repairs in action
In the West, the topography has also been difficult, with some works having to pause mid-stream while more resilient construction options are figured out. That’s been hard on everybody and has downstream impacts on schedules, material orders and traffic management. That all takes its toll and we are hugely appreciative of the people and communities who have and are continuing to endure sometimes lengthy road diversions and delays to their journey.
AT is integrating adaptation/resilience works with utility providers, e.g. Vector and WaterCare in areas where assets overlap and where utilities have indicated critical assets needing clear access during extreme weather events.
“During recovery works we’re upgrading the capacity of road stormwater assets and using best practice stormwater management as much as is possible.. In this way we’re injecting as much resilience as possible into each construction fix to cope with future extreme weather events in the face of changing climate conditions.”
With the end of the AT Road Recovery Programme in sight, what if “it” happens again?
Mr Wallace says while nothing is ever 100% certain, being prepared for the unexpected is key. With that mind, AT is trialling new electronic early flood warning systems at three flood-prone sites and is developing a landslide predicting framework using data from existing landslides and AI mapping across almost 8000km of Auckland’s local road network.
New Climate Technical Policy has also been built into all build backs to ensure climate hazard resilience which means all new designs will take future climate impacts, like increased rainfall intensity, flood levels and sea level rise, into account.
In the meantime, AT people and contractors will be pressing ahead this year to get the job done and to reconnect communities.
For more information visit Long-term road repairs from Auckland storms (at.govt.nz)
