Regional plans
Cities are so enmeshed in their surrounding regions that it no longer makes sense for them to be the sole focus of sustainable planning4, 8. Satellite images reveal patchworks of communities, industrial zones, farmland and natural ecosystems threaded by a web of transport links. For people and nature to thrive, the arrangement of land systems and water across the urban region (typically 70–100 kilometres in radius) must be managed holistically3. Urban region plans outline areas where water-supply protection, new compact communities, local food production, industrial centres and so forth are and are not appropriate, rather than pinpointing specific streets, developments and industries. They aim to sustain people and resources within the city and surrounding rings3, 8.
Some areas can accommodate more people better than others can. Inner cities and suburbs have too little land. Although city centres can be made more dense, for example by building upwards, they tend to have little green or outdoor space for families and suffer from excess heat, pollution and other environmental problems4. And unplanned growth beyond the city limits can destroy ecologically valuable land.