Hikuwai Bridge, north of Tolaga Bay. Photo: Kiri Allan

Building back better after Cyclone Gabrielle – Expert Reaction

Cyclone Gabrielle has washed out utilities, swamped roads, and claimed at least six bridges across the east coast and Hawke’s Bay.

With climate change expected to make storms intensify over time, the SMC asked experts what we can do to reduce how often our regional infrastructure breaks, and at what point we need to consider relocation or managed retreat.

Update (17 Feb): The Prime Minister has said the roading network needs a rethink, with relocation on the cards.

Professor Regan Potangaroa, Professor of Resilient and Sustainable Built Environment (Maori Engagement), Massey University, comments:

“Rural communities have unique needs and challenges that must be considered when making decisions about infrastructure development. The problem is, I don’t think that has been done.

“As a committee member on the Aohanga Māori Incorporation, a coastal beef and sheep farm of 7700 hectares east of Dannevirke, I have seen first-hand the impact of extreme weather events and infrastructure decision making. Cyclone Gabrielle caused significant damage to the roading infrastructure, loss of power and critically loss of communications. Loss of roads means that people and produce cannot move and the remoteness issues above and health issues for staff became critical.

“But the crucial one has been the loss of power. That means that phones and radio transmitters can’t be charged, that electric stock fences go down and stock roam; and freezers of food, required when you cannot go down the road to Countdown or New World, are lost after 2-3 days. Communications had been cut which made it difficult to confirm whether our staff and families were safe. Plus, the ability to assess what was happening on the farm and coordinate the allocation of resources. For example, the committee found out via Facebook of the loss of our $1m swing bridge which effectively cuts off transport access to the southern end of our farm at Mataikona. And we are having to go back to old school ways of farming in the short term. As a committee we are now looking at the issues of resilience through the purchase of a bulldozer, renewable energy sources, and a new bridge (once we ascertain why the first one failed). There will be definite impacts on our productivity and profitability and the committee is taking it as a wakeup call.”

What can we do to avoid constantly having to repair & rebuild the same infrastructure?

“It is important to prioritise resilience in the design and construction of new infrastructure. This means considering the potential impacts of extreme weather events, such as flooding and landslides, and building infrastructure that can withstand these conditions. Additionally, regular maintenance and inspections can help identify and address issues before they become major problems.”

Are there any innovations we could be using to “build back better” and improve climate resilience?

“Innovations such as renewable energy sources and green infrastructure, which uses natural features like wetlands and trees to manage stormwater and reduce the risk of flooding, can be a more sustainable and cost-effective approach to building resilience. Other innovations may include incorporating new materials, such as stronger and more durable concrete, and using advanced data analytics to predict and plan for extreme weather events.”

At what point do we consider relocation/managed retreat?

“Relocation or managed retreat may be necessary in some cases when infrastructure in vulnerable areas becomes repeatedly damaged and rebuilding becomes unsustainable. However, this decision must be made carefully, with consideration of the social, economic, and cultural impacts on affected communities. It is important to engage with affected communities and work collaboratively to find solutions that prioritise their needs and well-being. For us at Aohanga, retreat is not an option, and you get an immediate sense of the cultural difficulties such an approach would mean.

“But the singular innovation that has to be made is a move away from a solely cost benefit-based analysis for infrastructure decision making to one where wellbeing is at the centre of that infrastructure decision making. There are several advantages to this:

  1. Focus on long-term benefits: A wellbeing-centred approach prioritises long-term benefits to individuals and society, rather than just short-term economic gains. By considering the broader impacts on health, safety, and the environment, the decision-making process can lead to more sustainable infrastructure solutions.
  2. Holistic perspective: A wellbeing-centred approach considers the broader impact of infrastructure decisions on various aspects of people’s lives, such as health, social connections, and access to opportunities. This helps decision-makers better understand how different infrastructure projects will impact people’s lives and make more informed decisions.
  3. Inclusive decision-making: A wellbeing-centred approach involves engaging with communities and stakeholders to understand their needs and preferences. This ensures that infrastructure decisions are made in a more inclusive and democratic way, with the input of all relevant parties considered.
  4. Improved equity: A wellbeing-centred approach considers the impact of infrastructure decisions on different segments of the population, including marginalised and vulnerable communities. This helps ensure that infrastructure investments benefit everyone, rather than just a few privileged groups.
  5. Enhanced resilience: A wellbeing-centred approach prioritises infrastructure solutions that enhance community resilience to shocks and stresses, such as natural disasters, economic downturns, and public health crises. This can help communities better withstand and recover from disruptions, leading to better outcomes for all.

“In summary, a wellbeing-centred approach to infrastructure decision-making has the potential to lead to more sustainable, equitable, and resilient outcomes that benefit all members of society, including the rural sector. It’s a no-brainer.”

No conflict of interest declared.

Dr Sandeeka Mannakkara, Lecturer, Department of Civil and Environmental Engineering, University of Auckland, comments:

“It is high time that we as a country move away from reactive responses to natural hazard events and adopt a proactive approach, to break away from the post-event “repair and rebuild” cycle. Proactive management of infrastructure requires a commitment to understand updated risk levels as per climate change projection models, thoroughly review the ability of our lifelines infrastructure to cope, and put the necessary resources in place to upgrade vulnerable infrastructure and innovate.

“Whilst there is still debate in the engineering community as to the accuracy and reliability of climate projections, Cyclone Gabrielle has illustrated the need to be diligent and cautious in making sure our infrastructure is ready for future catastrophic events in order to minimise impacts on communities.

“The reconstruction and recovery effort following Cyclone Gabrielle offers an opportunity to consider necessary upgrades and changes to our infrastructure systems taking into account the advised climate projection scenarios for New Zealand in order to truly build back better. As stipulated in the National Climate Change Risk Assessment for New Zealand report, the scenarios include a medium to low emissions pathway and a high emissions pathway, projected at different timeframes including the present, 2050, and 2100. Considering these parameters will provide guidance on the improvements needed to our infrastructure to cope better with possible future events. It is important to note that proactive infrastructure management also requires the acceptance of “unknown” levels of risk and considering alternative ways of improving the resilience of infrastructure, such as adopting a network approach by relying less on single infrastructure assets and improving redundancy through creating more dependable infrastructure networks.

“As presented in our Build Back Better Framework and Build Back Better Tool, upgrading our built environment to be structurally resilient is only one aspect of building back better to improve climate resilience. It is unrealistic to assume that the built environment can be solely relied upon to prevent and minimise risk to our communities. Building back better to achieve true resilience requires a holistic approach through also considering changes to land-use, implementing effective early warning and disaster risk reduction education of stakeholders and communities, enhancing social and economic resilience of communities, and having institutional mechanisms, legislation, and monitoring and evaluation in place that supports these activities.

“Although highly disruptive, it is important to discuss options such as relocation and managed retreat with communities in high-risk areas such as our coastal areas who have been facing repeated damages from weather events. It will become unsustainable to rely on infrastructure alone to minimise losses as hazard events continue to exacerbate in the future. Honest and open discussions about past, present and projected risks to these areas need to be had with communities in order to make collaborative decisions on ways forward.

“Whilst built environment and planning solutions are half the battle, long-term resilience and recovery potential of communities lie at the grass-roots level. The Cyclone Gabrielle disaster is a grave reminder that in the wake of disaster events, the first responders are always neighbours, whānau and the local community. Therefore, in building back better it is highly important to also make genuine efforts to build resilience within communities by finding ways to empower them with accurate knowledge on disaster and climate risk, assist with grass-roots disaster preparedness, and support the building of strong social networks.”

No conflict of interest. 

Professor Suzanne Wilkinson, College of Sciences, Massey University, comments:

“Building back better is an option which allows us to consider a range of elements for recovery and reconstruction. Essentially this is a planning framework to help understand what needs to be done, and how to make it better. Building back better asks us to consider a whole range of issues – for instance whether we should be re-building on the same piece of land. To avoid the problems of constantly having to repair & rebuild the same infrastructure after disasters, we need to use frameworks like building back better to create more resilient infrastructure. Resilient infrastructure can withstand multi-hazard shocks and stresses and is built to last across future generations, but will cost more.

“Building back better allows us to focus on the things that matter (such as safe communities, strong infrastructure, regained livelihoods, buildable land) – the framework we developed and our book gave a full explanation of why you should use the framework and many case studies of how to create better resilience through the recovery process. The book also created indicators for recovery which can be used to track progress.

“So to improve climate resilience we need to stop rebuilding in unsuitable places. If we do build in those places we need to change how we build and incorporate higher resilient features (using better materials or different parameters). We need to build above code and take a multi-hazard, intergenerational approach.”

Conflict of interest statement: “I belong to a small consultancy, Build Back Better NZ.”

Professor John Tookey, School of Future Environments, AUT:

“Rural and regional infrastructure is always in short supply. You can never have too much infrastructure. Small populations spread thinly present a particular challenge for local authorities and service providers. Revenues from small populations are small, however the investment in horizontal infrastructure they need to service communities is disproportionately large. This is one of the rationales for the desire for urban densification we see in cities like Auckland. Dense populations are much more financially sustainable to provide compared to thin rural populations.

“As a result, there is a strong requirement to ‘make the best’ of any infrastructure that is put in place. Roads are patched, repaired or upgraded. They are only very rarely replaced. The same is true of water supplies, bridges, drains, stormwater systems etc. Pretty much any horizontal infrastructure you can think of has the same mantra: patch, repair, upgrade. Roads have a particular impetus since they shape communities rather than vice versa. The existence of a road tends to drive ribbon development out of settlements. The longer the road is in service the more likely it is to remain in service – because there is now a ribbon development that needs to be supplied as well as the communities at either end. Consider the Roman road network in Europe and North Africa. Created over several hundred years starting some 2,000 years ago. The vast majority of those roads (the routes at least) are still in effect in operation. Why? They are dead straight and adopt the shortest viable distance between population centres. These desirable features of a route don’t tend to change. Population centres themselves tend to stay in the same place. Hence – and logically – roading infrastructure tends to follow those self-same routes. These Roman roads lasted over the years by patching, repairing and upgrading.

“Bridges are a slightly different, though related, matter. Historically, bridges tend to be built at narrow river crossings that are close to natural fords. Narrow is good because it means the bridge can be shorter. However narrow is not so good because the flow rate through the narrow part of a river tends to be higher than elsewhere – hence bridge abutments can be subject to scouring at a higher rate than elsewhere. Sometimes it is almost like nature is constantly fighting against the needs of humans. Once a bridge is in place it links communities and there is an expectation of that bridge being there for the future. Once constructed it is hard to imagine it being removed from service. Imagine a bridge like the Auckland harbour bridge. Until it was constructed in the 1950s ferries were the norm. Now it exists there is an expectation to its continued existence. All the development on North Shore is dependent on it. Most of the economic activity on the top half of the north island crosses it at some point. What would be the value of the road system of most of North Shore without it in place? Very limited. Certainly not the motorway. Once again bridges are subject to patching, repair or upgrade. Replacement is a tortured question and continues to exercise politicians in both Auckland and Wellington. Will it need replacing? Yes. Guaranteed. When patching, repair or upgrade are no longer possible.

“How is the decision made to replace such infrastructure then? Very simply this comes down to a financial decision made at the point when the cost associated with patching, maintenance and upgrade over a period of years starts to approach the cost of replacement. Typically it can take a number of years of escalating repair and maintenance costs before politicians finally take the plunge. Hence the continuous discussions around the future of Auckland harbour crossing ongoing for the last couple of decades.

“What is the future? Infrastructure will always be in demand in one form or another. In rural communities efforts need to be made to reduce the demands being placed on highly expensive horizontal infrastructure. This can be taken by increasing the investments made in local power generation (windmills and solar in particular) to reduce the demands for power transfer infrastructure. Maybe some tax breaks or other financial incentives to make such micro-generation more attractive is the way to go. Speaking as a recent victim of rural road closure and power outages from the grid, I can tell you that having my own solar system augmented with a petrol generator makes a huge difference. Plus it takes the load and time pressure off the contractors undertaking repairs. Insulating rural homes reduces power consumption – again another way to reduce pressure and increase resilience in affected communities. Similarly improving internet (especially satellite based) and mobile phone services means that rural communities can continue to operate remotely if required rather than rely on road access and the restoration of horizontal services. Finally maximising the degree to which sewage and grey water can be managed and processed at a microlevel has to be a positive outcome. On the one hand investment in managing stormwater run off from housing developments reduces the amount of water that storm systems need to deal with. Hence mandating and subsidising grey water holding tanks can reduce the effects of storm water surges – so likely should be subsidised. On the other hand, septic tanks are all well and good, however increasing on-site processing in reactors can improve the quality of water heading into the environment and reduce the effects of storm events. Once again some subsidies may be helpful to make this a more common solution for homeowners.”

No conflict of interest declared.