How to Plan Tomorrow’s Cities?

Context and Motivation

Today’s urban planning is more complex than ever: climate change, the housing crisis, natural hazards, and chronic disease mean that planning decisions must consider multiple objectives. Aotearoa New Zealand’s planning landscape is also shifting with the recent NPS on Urban Development, the likely introduction of the Strategic Planning Act, and climate risk requirements of the Zero Carbon Act. As a result, future development must enable sustainable and healthy lifestyles, reduce exposure to natural hazards and pollution, and promote equity and community cohesion, often among many other objectives.

Aim

To support this planning, we are developing a sophisticated tool that supports housing agencies, councils, and iwi to identify favourable areas for urban development or intensification that maximises the co-benefits between the community’s objectives.

Method

We use a multi-criteria spatial optimisation approach using a genetic algorithm that evaluates and improves spatial plans based on the community-specific objectives and priorities. Our proof-of-concept tool currently discourages development in areas exposed to hazards and encourages development near key centres.


Want to see the results of the current tool in action?

As a case study, we ran the tool using Ōtautahi Christchurch’s projected population increase with the following objectives:

The objectives were weighted to be equally important, eg. being in a tsunami zone is equally as bad as being far away from key activity areas, only to show the effectiveness of the tool.

As seen below, the tool found priority areas for development/densification where there was clear evidence of decreasing exposure to natural and climate hazards, whilst increasing the distance to key activity areas and utilising residentially zoned land.