The city has to go somewhere. Hemmed by two oceans and constrained by clogged motorways, growth upwards takes stress off the transport networks and green belt at the edge of the city.
But managing this transformation of Auckland and the development of new urban spaces is critically important.
Groundbreaking research being conducted overseas in environmental psychology and neuroscience is discovering strong connections between cities and the brains of their residents.
In 2011 a team of German researchers at the University of Heidelberg used brain scans to measure the neural activity of students doing maths tests.
When the students became stressed out, different parts of the brain would activate in students living in cities compared to students living in the countryside.
The researchers discovered that the amygdala, which processes emotion, became active only in city dwelling students. This led the researchers to conclude that urbanisation reduces our ability to manage stress.
This may help account for the fact that schizophrenia is twice as common in people raised in cities compared to those raised in the countryside. As city size increases so too does risk.
New research due to be published this year in the Journal of Experimental Psychology, by British psychologists from the University of London, measured difference in attention and focus on a simple task between people living in cities and people living as traditional cattle herders in Namibia.
The researchers found that people living in cities have less focused attention compared to rural dwellers.
As this research becomes available and expands our understanding of the effect of cities on our brains, urban planners, architects and psychologists are drawing new connections as to how we can design and use cities that support healthy thinking. For example, psychologists in 2008 discovered that children with ADHD who went for a 20-minute nature walk showed markedly improved focus.
And in 2005, an Italian psychologist found that attentional capacity could be improved by exposure to pictures of natural environments like forests and lakes. To maintain attention capacity we need to ensure adequate access to parks and natural settings.
In 2012 researchers in the American city of Baltimore discovered that across various neighbourhoods "a 10 per cent increase in tree canopy was associated with a roughly 12 per cent decrease in crime".
Good urban design that integrates accessible parks, tree-lined streets and well-designed new buildings will be critical in minimising the negative effects of urban living on the brain.
If Auckland is to achieve Len Brown's vision of making us the world's most liveable city then city planners should consider whether allowing up to 800 homes to be built on the old Manukau Golf Club grounds fits with this vision.
If we are going to have an intensification of apartment blocks are we going to ensure that new designs include shared rooftop gardens where residents can rest?
Preserving green spaces and developing new spaces of rest and relaxation will be critical to supporting healthy brain development. The stakes are high. A badly designed city could lead to poorly developed brains.
Chris Bradley is a freelance urban planner living in Auckland.