Auckland flooding: Wayne Brown - how did homes get built in risk-prone places?

OPINION

Auckland was battered by Cyclone Gabrielle on top of the wettest day on record in recent weeks.

Beyond much-needed improvement in emergency management and communications, the big issues are: How do we manage the recovery? What should be recovered or rebuilt? Who should pay for all this devastation? And how did we get into this state of high risk and low preparation?

There are a lot of players: Council; CCOs (council-controlled organisations) ; government, in its many forms from the political to the Ministry of Social Development and the Ministry of Business, Innovation and Employment; emergency services; homeowners; insurance companies; property developers - and absolutely the Environment Court, whose poor decisions have left a nasty legacy.

Thinking about what happens next in no way diminishes our concern and sympathy for those who suffered. I urge those who weren’t as badly affected to show some generosity by donating to the various appeal funds, especially the Auckland Council Emergency Relief Fund, if you live in the region.

In Auckland, some generalisations can be made. The devastation was largely confined to expensive properties too close to cliffs and more modest properties in valleys and flood plains, in some cases exacerbated by poor building technique choices, even by well-established builders and government agencies.

Illustration / Rod Emmerson

How did these risky homes get where they are?

In too many cases, houses were allowed to be built where there was a previous history of land instability and stormwater problems. The lessons of the past had either been forgotten or central government mandates had changed things adversely, or the council positions had been overruled by Environment Court decisions.

The council had taken years to come up with a Unitary Plan at a huge cost that allowed for way more new houses than needed given the slowdown in Auckland’s growth trajectory. The bi-partisan government mandate forcing councils to accept three homes of up to three storeys on most sites, regardless of whether the infrastructure was in place, now looks quite ridiculous.

The cyclone and storms indicate that the right infrastructure was not in place, and may not have been well maintained by the council or homeowners.

In addition, the public’s capacity to drop bottles, plastic, tyres, supermarket trolleys, and an endless supply of other trash into the stormwater system resulted in horror stories for many citizens.

Sadly, coastal communities such as Muriwai faced tragedies for the second time. A cliff failure back in 1965 cost two lives and the council made it hard to build on these coastal slopes. Older engineers were taught to be very careful of such coastal cliffs.

A house is damaged beyond repair after a landslip at Muriwai. Photo / George Heard

“Cliffs grow backward” is the mantra used by many, including myself, to talk people away from these lovely but risky views. Our coastal cliffs retreat at an average of three metres each century, but it’s hard to say whether a property is above or below the average and where exactly it is in the 100-year cycle.

In areas impacted by slips, where red-stickered houses look to be in good condition, the council directive against building there was most likely overruled. In some cases, the houses are okay – it’s the land that failed.

The point is that the council needs to be able to say “no” and for the decision to stick.

There are similar stories about housing in flood plains.

The insurance industry seems keen to get on with paying up and moving people on – they will definitely be increasing premiums for everyone, but especially for those on cliffs and in valleys. Home values will change quickly as a result of these floods and buyers will be more cautious of risks.

Cliffsides have collapsed, bringing the edge closer to houses in Stanley Pt. Photo / Brett Phibbs

Sadly, those whose houses flooded in low-lying areas are generally less able financially to take the hits and the government will need to think carefully about its response. Many are uninsured and handling this issue, without sending the wrong message to those who are insured, will be tricky.

Time spent with building inspectors visiting these low-lying houses revealed some very poor building choices. Why were so many built on concrete slabs right at ground level, often by well-known firms and government agencies? So they could have a drive-in garage, was the answer, but cars are quite happy outside or under a carport. In many places, the garage had become an additional bedroom and they flooded.

Why not build tanalised plywood floors up off the ground? Way cheaper, quicker, more flood-resistant, and not needing a flat site.

Why are our houses dominated with timber stick frames covered in gib board, a hopeless material when wet? Why allow polystyrene under the concrete slabs, which floated when flooded and tilted houses making them write-offs?

This is just the tip of the recovery iceberg.

In spite of the huge budget pressures facing council, we need to start the Big Auckland Fix-Up of flood-related problems, and this will be my focus.

Auckland Mayor Wayne Brown inspects a drain in Māngere after flooding events. Photo / Supplied

We need to invest more in stormwater, including the small quick fixes suggested by our local boards, and initiate a big resilience project that includes calling on the best brains in flood mapping and stormwater control.

The weather bombs will just keep getting worse.

I am determined that the council and everyone involved will learn the lessons from these floods, and not have another flood report that goes ignored. We need to stop making the same mistakes and having to do the same recovery work over and over.

- Wayne Brown is the Mayor of Auckland.