More than a month after the disaster, there is evidence everywhere of the flooding that plunged Auckland's Wairau Valley underwater.
There is still debris near the stream and some broken fencing. Some industrial buildings nearby sport the dreaded yellow stickers. They look abandoned.
"There was a six-hour period of time where the flows down Wairau Valley were such that we had an Olympic pool flowing past every thirty seconds," Auckland Council's Healthy Waters head of planning Nick Vigar said.
He took 1News on a tour of some parts of the stormwater network to show what worked — and what didn't.
Our tour began at Sunnynook Park, just up the road from the Wairau Valley industrial area.
The park, covered in sports fields and walking paths, is surrounded by a tall embankment, and along one side is a large water outlet.
"Pipes will only get you so far, and you can never design a big enough pipes to deal with those really extreme events," Vigar told 1News.
The essential tool to fighting floods is green space — ideally lots of it.
In a flood, water deliberately pools in the field, filling the field. A gate in the water outlet controls the flow downstream
And that's exactly what happened on January 27. The field filled. And then it overflowed.
"This is expected to store a so-called one-hundred-year event, as it happens the January 27 event was bigger still," Vigar said.
That night a record amount of rain fell, at a pace that few cities in the world could cope with, he said.
But as rainstorms like this become more common due to climate change, and some areas dealt with repeated flooding, Vigar said engineered fixes were limited.
"The reality is, there are only a small number of properties where there is an infrastructure solution that will lower the flood risk," he said.
"Where that exists, and the economics are good, we'll go and do that but the reality is for most of the properties that flooded on January 27, if that event happened again, people need to prepare because there is no long term solution for them."
There were many spaces in Auckland that government agencies and developers had designed to help mitigate flood waters. 1News visited another near Sandringham, bordering a stream that had flooded surrounding homes. The area had been planted up, the stream structured — partialy built up with rocks but still allowing room for water to move against a soft river edge in places. It had helped, although some nearby homes still flooded.
But Vigar said there was only so much space available for projects like this.
As Auckland deals with a flooding crisis, it is also dealing with a housing crisis. Demand has outstripped supply for years, and huge subdivisions have developed in previously empty land. Many contain detached, single-family homes with backyard — also known as the typical Kiwi dream.
But Auckland University urban planning expert Tim Welch said some of those were a disaster waiting to happen.
"You've got a roof that displaces all that water that was before soaking into the ground, and the driveway is cement so that displaces water," Welch said.
Add lawn, non–permeable soil, certain types of planting, and it would displace a lot of water fast.
"It's a combination of things that has made us a lot more vulnerable."
But he said intensification was actually a good thing — if designed properly.
"The knee jerk reaction after flooding is looking at intensification — thinking that it must be one of the contributing factors to flooding," he said.
"The fact is, the denser we can build in certain areas, the more green areas we can have."
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