After the flood

Just over a year on from the devastating floods that hit New Zealand in early 2023, Alex Cartwright, technical director of resilience and emergency management at environmental and engineering consultancy firm Tonkin + Taylor, reflects on next steps for flood preparedness

Waiho i te toipoto, kaua i te toiroa | Let us keep close together, not wide apart

It’s Friday 27 January 2023, the height of summer in Auckland, New Zealand. The city, found in the north of North Island, is buzzing in anticipation of the long Auckland Anniversary weekend, including an Elton John concert for nearly 50,000 fans. At 7pm, less than 30 minutes before the concert is due to start, organisers call off the event due to significant rainfall.

Twenty-four hours later, four people are dead. Auckland has experienced its wettest day on record. Damaged infrastructure is littered across New Zealand’s largest city. Auckland International Airport is shut due to significant flooding. Flood water on motorways could be measured in metres. Many houses are uninhabitable, essential services disrupted.

The building assessments that followed revealed 277 properties issued Red placards (unsafe to enter), 1,615 issued Yellow placards (restricted access), and 2,566 issued White placards (minor damage). Roads were strewn with flooded cars, buses and other vehicles. Over 57,000 insurance claims and 1,300 injury claims were filed relating to the floods. Reviews that followed would reveal that the warning system meant to alert communities had failed – warnings were either issued after people were already flooding, or not at all.

Rainfall significantly exceeded the usual design standards for flood protection and wider infrastructure (the 100-year event, more accurately depicted as a flood with a 1 per cent chance of occurring in any one year). More rain fell on that single January Friday than was expected for the entire month for Auckland. All 1.7 million people in the Auckland region, a third of New Zealand’s population, had experienced an extreme weather event. Worse was to yet come.

From bad to worse
Two weeks later, Cyclone Gabrielle hit the top of New Zealand’s North Island, killing 11 people and causing widespread damage. Over 10,000 people were estimated to have been displaced, and over 225,000 homes lost power. This was more than January’s flooding after with heavy rain; it was land movement across critical infrastructure impacting roads, utilities and communities. Over 140,000 landslides were mapped following the cyclone, isolating communities for far longer than flood waters.

Hawke’s Bay, world famous for wine and fruit, was one of the hardest hit areas. Homes, orchards, and wider productive farmland were left covered in thick silt. For some, escaping their properties was only possible from their rooftops. In Tairāwhiti Gisborne, Cyclone Gabrielle caused 50,000 landslides across an area of 8,000 square kilometres, 3 per cent of New Zealand’s total land area. Auckland did not escape unscathed, with Cyclone Gabrielle causing havoc and destruction here too.

Less than 50 days into 2023, the death toll stood at 15. Hundreds of thousands of people were impacted and 115,000 individual insurance claims were made. The insured losses for New Zealand from these weather events was costed near $4bn New Zealand dollars by mid-2023.

A country usually known for its earthquakes and other geohazards, New Zealand was hitting the headlines globally for extreme weather. Flooding is New Zealand’s number one hazard by losses, but is not always front of mind, thanks to the fact that we are the second most at risk country in the world from natural hazards.

The scale of the 2023 severe weather events was 10 times larger than previous recorded losses. Were these events and outcomes foreseeable or even preventable? What lessons can be learned here and abroad?

Fragmented strategy
There is no single flood management statute in New Zealand. Responsibilities are devolved locally, with reforms from 1987 to early 1990s leading the shift away from central government in policy-setting and funding.

While the Resource Management Act 1991 enables central government to provide national direction on managing flood risk for local government, no statements, standards or guidelines have been provided since the shift began in 1987. The various acts covering flood management are administered through regional and territorial authorities who set regional and local policy through long term plans, regional policy statements, and regional/ local plans.

In many parts of New Zealand there is ambiguity over the jurisdiction on land drainage and wider flood management. This can lead to inconsistencies in applications of key acts, statutes and responsibility across different hazards. Inconsistency can also occur within a region as different types of flood hazard are administered by differing agencies.

New Zealand has an outdated and fragmented policy landscape for flood hazard management. We’ve long known this to be case, and the events of 2023 further exposed the scale of the challenge. The need to reconsider how flood risk management is delivered is critical on many levels – from economic and financial to social and community safety.

The international picture
In 2007, the UK was hit with devastating floods that cost 13 lives. The response was the largest peacetime rescue operation in British history and the widest-ranging policy reviews ever conducted in the UK.

The Pitt Review found flood risk management lacked coordination and structure, and paved the way for the Flood and Water Management Act 2010, which provided a new framework for managing flood risk, including greater clarity on roles and responsibilities. This included improved coordination across agencies and requirements to improve public awareness of flood risk.

New Zealand’s population at the time of the 2023 floods was one tenth of the UK’s in 2007, yet we saw comparable deaths, with insured losses two thirds of those amassed by the UK in 2007. The lessons identified in the Pitt Review may be 15 years old but they are just as applicable in New Zealand today as they were in the UK in 2010.

A year on
New Zealand is making steps toward recovery. The establishment of the land categorisation process has helped support homeowners in making decisions around properties identified as at-risk. This process focuses on establishing whether land and property is exposed to intolerable risk and, if so, enables a financial buy-out.

Although not a legislated act or policy, signs of a managed retreat process are emerging – where action is taken to permanently relocate people, property and infrastructure to lower risk areas . While this process helps manage existing risk, controls have not, as yet, been implemented on new development areas: land and property still covered in silt have neighbouring sites consented for development, against the advice of hazard specialists.

New Zealand has recovered from major events in the past and continues to showcase expertise and leadership in recovery. The Transport Rebuild East Coast (TREC) Alliance has been established to plan, organise and deliver much of the highway and railway recovery and rebuild work. The pace and scale is impressive: 420 sites have so far been identified for recovery, with over 30 per cent completed through design and construction.

What next?
It is easy in hindsight to reflect on decisions made in minutes. That said, there is clear opportunity to learn from 2023 and previous events. One question is whether there is value on increased investment in prevention, readiness and response to help reduce recovery efforts.

Current funding mechanisms default costs of disasters to local authorities, meaning that it is the people locally who are paying through their council tax. There are opportunities to seek support from central government, but with no contributions guaranteed. A big disaster brings attention and focus, as well as looser purse strings. The result is a funding system that tends towards managing flood events after they occur, rather than trying to prevent them.

We can focus on the differences between jurisdictions, weather characteristics, response efforts and funding mechanisms. But one consistent factor persists – our communities remain at risk. So how does a country at risk of nearly every natural hazard event effectively prepare for and manage those risks?

By engaging people early and often, and communicating risk to them about the risks they face, we can influence outcomes before, during and after events caused by natural hazards. Communities invested in prevention and wider risk management can help focus and drive policy and legislative changes.

While lack of funding is always listed as a reason for inaction – whether around community engagement or any other flood preparedness measures – it is time we look beyond this to establish ways to learn from identified lessons, locally and internationally.

It is too early to say whether the 2023 events will be the flood of change New Zealand needs. However, as practitioners and interested parties within CIWEM, there is a responsibility for each of us to push for positive change that enables communities to thrive.

This post was originally published in the Summer 2024 issue of The Environment.