Health consequences of transport patterns in New Zealand's largest cities

Transport is a well-known determinant of health, through physical activity, air pollution and injury pathways. New Zealand has a highly car-dominated transport system, but cities differ in the amounts of walking, cycling and public transport use, reflecting different urban planning priorities over time.

Using the Integrated Transport and Health Impacts Model, adapted for New Zealand, we quantified the likely changes in health and greenhouse emissions if Auckland, Hamilton, Tauranga, Christchurch and Dunedin Cities had the same mode share for cycling, walking, public transport and car use as Wellington City, which currently has the highest levels of sustainable travel.

All cities modelled would have better health, due to a reduction in morbidity and mortality from injury and air pollution and through increased levels of physical activity, if their transport systems resembled Wellington's. Carbon emissions from light passenger transport would fall also. The magnitude of these effects varies considerably by city.

Transport funding in recent decades that has prioritised private car use has had detrimental effects on the health of New Zealanders. New Zealand requires better accounting of and accountability for the health and carbon impacts of decisions on transport projects, at both local and national levels.