Kaikōura Earthquake RecoveryDelivering resilient infrastructure for the community

Bringing stakeholders and contractors together

In December 2016, the North Canterbury Transport Infrastructure Recovery Alliance (NCTIR) was formed comprising key stakeholders, Waka Kotahi and KiwiRail, and four of New Zealand’s largest contractors.

Their task was to quickly restore the road, rail and harbour infrastructure that are critical lifelines to the surrounding communities. With this in mind, the NCITR alliance committed early on to support the goal of reconnecting these communities by the end of 2017.

Waka Kotahi approached Aurecon in April 2017 for a design concept that would increase the safety, reliability and amenity for a 60 km stretch of this challenging coastal route. In an effort to accelerate the development of solutions for inclusion in the rebuild, Aurecon fast tracked the options process and delivered a concept design including cost estimates, economic justification and consenting requirements within a six-week timeframe. In an effort to accelerate the development of solutions for inclusion in the rebuild, Aurecon fast tracked the options process and delivered a concept design including cost estimates, economic justification and consenting requirements within a six-week timeframe.

Aurecon fast tracked the options process and delivered a concept design including cost estimates, economic justification and consenting requirements within a six-week timeframe.

The team developed a detailed 3D digital InfraWorks model to work through the entire 60km route, testing various design solutions with the client in a real-time digital environment. The interactive nature of the 3D model really helped Waka Kotahi to see the situation from a different perspective, allowing them to move forward quickly with clear decisions.

“For the Clarence to Oaro concept design workshops, Aurecon had prepared large roll out plans spread across the tables, but it wasn’t until we switched to the screen to see the corridor in 3D that the practicality of options came to life. Being able to develop concepts “on the fly” and see the potential environmental impacts was invaluable in considering options. The 3D Digital Technology turned the concept into reality for the Waka Kotahi Board and Executive Team, enabling them to clearly see the customer outcomes being delivered” says Michael Blyleven, System Design Manager, Waka Kotahi.

Delivering this work successfully ahead of schedule led to Aurecon Major Projects Director Tim Watterson being appointed by NCTIR to lead the overall design programme as Design Director, managing over 300 designers.

Building climate change resilience into Kaikōura’s road and rail network

As part of the recovery effort, the long-term resilience of the road and rail network was kept in mind. Due to its location, with the road and rail sandwiched between the ocean and steep cliffs, it is difficult to make the infrastructure truly resilient.

With research identifying a stronger link between climate change and extreme weather events, the coastline and transport links of Kaikōura will become increasingly at risk. These extreme weather events risk further sections of hillside disturbed by the earthquake causing new landslides that will disrupt transport links.

Loose rocks and boulders will shed off the canopy and beyond the road, keeping drivers safe. While there are some examples in Europe, this is the first time a canopy of this kind has been used in the Southern Hemisphere.

The earthquake caused the seabed to rise up several metres in some areas of the coast, and so it became critical to protect the network from the physical impacts of rising sea levels created by climate change. Two kilometres of sea walls were also added to prevent further erosion and minimise the impact of rising sea levels and storm surges on the infrastructure over time.

These elements ensure that the infrastructure is more likely to withstand the impacts of climate change and future natural disasters.

Leading the rail recovery

Aurecon Rail Zone Design Manager, Haden Walters, said, "Given the narrow transport corridor and the close proximity of the road and rail, it has been essential for teams to work closely with each other. We approached the rebuild task by sequencing work from either end, with the goal of meeting in the middle.”

The Main North Line railway, prior to the earthquake, provided passenger services and carried over 1 million tonnes of freight per year. To support the ambitious timeline to get this crucial transport network back up and running, Aurecon became the main provider of rail engineering services. From tunnel inspections and design to flood modelling and storm water design, Aurecon teams worked with NCTIR to deliver design concepts that would not only reconnect communities, but also protect this lifeline for them in the future.

"The level of personal commitment and teamwork across NCTIR has been quite humbling and a career highlight for many. It’s great to have re-connected communities and seeing first hand what this means for the region."

Tim Watterson, Major Projects Director, Aurecon

Reconnecting North Canterbury communities

One of the main challenges of the programme has been the fact that the affected road, rail and marine transport links are critical lifelines to the surrounding communities. Freight and passenger trains ground to a halt, whale and sea life watching tours were stranded in the marina due to the reduced water depth, and other tourism related businesses saw their income flown out of town with the evacuation of tourists from the area. With this in mind, the team committed early on to support the goal of reconnecting these communities by the end of 2017.

The critical Main North Line railway between Picton and Christchurch was re-opened less than a year after the earthquake, in early September 2017. While Kaikōura’s harbour was re-opened exactly one year after the earthquake on 14th November 2017, and the main coastal State Highway 1 link between Christchurch and Picton followed in December 2017.

The 140m Irongate bridge delivered as part of the recovery set a record for the fastest seven span bridge built in New Zealand.

The 140m Irongate bridge delivered as part of the recovery set a record for the fastest seven span bridge built in New Zealand. This was possible through an intentional design that was a) based on widely accepted standards with no bespoke elements and b) developed in collaboration with the construction team based on what could be built fastest – considering available plant, material supply, construction workforce planning.

The successful re-opening of the key transport routes and ongoing efforts to not only re-build, but also improve the safety and long-term resilience of the road and rail infrastructure, are testament to the hard work and collaboration of all the teams involved and the neighbouring communities.

"What we achieved in the space of a year is simply outstanding! Many people didn’t think we could do it. Everyone has worked extremely hard under challenging conditions. The level of personal commitment and teamwork across NCTIR has been quite humbling and a career highlight for many. It’s great to have re-connected communities and seeing first hand what this means for the region," concludes Tim.