Urban design experts call Auckland's catastrophic flooding a wake-up call to plan cities better

Urban design experts say Auckland's catastrophic flooding is a wake-up call and we must plan our cities better to avoid such widespread damage.

Science shows the frequency of extreme weather events will increase as the planet warms, but with proper planning we can be better prepared.

Precisely why this happened to several homes in Mangere will be unknown until they are properly assessed. But urban design experts say it's not too soon to learn critical lessons from this disaster.

"We need to stop building in places that are at risk from natural hazards and also we need to stop building in places that make the flooding worse," said Canterbury University civil engineering Senior Lecturer Dr Tom Logan.

Because the world is on track to heat as much as 2.6C this century and scientists say that means more extreme weather.

"This is climate change, it's happening now, these intense weather events - we need a change in the way we plan in our urban areas to work with nature rather than against it," warned Green MP Eugenie Sage.

The change is already happening in some areas. Parts of Auckland did not suffer in the extensive flooding.

The Auckland development of Stonefields has been designed using the 'Sponge City' concept - you've got a floodable park and a wetland, both of which are designed to soak up the water.

"We need to make our cities more permeable, more ways for water to soak into the ground, that's from berms, plantings, less of the concrete, less asphalt," Sage said.

The deluge wrote off 33 cars in a Browns Bay panel beaters - it's the third time it's been flooded.

"The infrastructure around here is terrible. I think the infill housing has a lot to do with it," Mike Phillips from Holgate Panel Beaters said.

But experts say intensification actually will protect us if planned properly.

"We need to stop urban sprawl into those natural areas and our agricultural areas, which would previously have stopped the water from flooding our urban areas," Dr Logan said.

Auckland Mayor Wayne Brown faced flack for this comment which many felt lacked empathy.

"Some of those houses, when you think about it, actually shouldn't have been where they are," he said.

Though perhaps misjudged amid a natural disaster that left people homeless, Brown's words were echoed by others.

"All too often we've had housing development occur where it shouldn't," Sage said.

"It just doesn't make sense to continue to build in the same places and then rebuild, only to be hit by the same disaster again and again," Dr Logan added.

Because many say Auckland's flood is a wake-up call and one we can't afford to ignore.