Walking is the most space-efficient form of transport and makes the best use our streets.

The figure below shows the space used by each mode of transport. This can enable a conversation about space being used in the best way possible, particularly when space constraints are an issue in growing towns and cities. 

Infogram of a space each person use according to mode of transport

Space used per person according to mode of transport (Source: Urban Mobility Plan Vienna)[1]

Repurposing street space for more efficient travel modes increases the total street capacity; refer to the Global Street Design Guide for a useful comparison of car oriented versus multi modal streets.[2]

Traffic in urban areas, and the consequent economic cost, is a central consideration for assessing various modes of transport. A study commissioned by the Waka Kotahi estimates costs of congestion to be in the region $1.25 billion per annum.[3]

A shift to more walking or riding, particularly for short journeys during peak periods, could improve the capacity of our transport systems:

  • Australian estimates suggest that depending on the location and time of day, a mode shift towards active travel can equate to an ‘avoided cost’ of around 20.7 cents per kilometre walked or cycled.[4] To realise the full benefits, measures would need to be taken to constrain induced motor vehicle traffic.
  • Litman (2017) compiled various congestion reduction strategies and concludes that “Compact, multimodal cities…tend to have more intense congestion (greater peak-period speed reductions), but lower congestion costs (fewer annual hours of delay per capita) due to lower auto mode shares and shorter trip lengths, which reduces congestion exposure (the amount residents must drive during peak periods). More dispersed, automobile-oriented cities…tend to have less intense congestion but greater congestion costs”.[5]
  • Based on research in three Australian cities, Donovan states “if congestion is defined in terms of per capita delay, then investment in non-car transport infrastructure can cause mode shift and support increased density (people/jobs) which together reduce per capita delays, even if road travel-times remain constant”.[6]
  • Bento et al. (2005) studied a sample of households in 114 US cities and predicted that the “effect of moving…sample households from a city with measures of urban form and public transport supply the same as (car-centric) Atlanta to a city with measures the same as those of (compact and transit-oriented) Boston is to reduce annual VMTs (vehicle-miles travelled) by 25%”.[7]
  • About 40% of peak traffic in Auckland is related to education; more students would walk if the routes to school were safer and more convenient.[8]

References

[1] Stadt Wien. (2015). STEP 2025 - Thematic Concept - Urban mobility plan Vienna(external link) - Short report

[2] NACTO. (2015). Global street design guide(external link)

[3] Ian Wallis Associates Ltd, Wellington. (2013). The costs of congestion reappraised Waka Kotahi NZ Transport Research Report 489.

[4] Department of Infrastructure and Transport. (2013). Walking, Riding and Access to Public Transport(external link)

[5] Litman, T. (2017). Congestion Reduction Strategies. Victoria Transport Policy Institute(external link). Accessed 1 April 2020

[6] Summary provided in personal communication, see also Donovan, S. (2018). Transport Outcomes and Location Choice. MOT Knowledge Hub(external link) Accessed 1 April 2020

[7] Bento, Antonio M., Cropper, Maureen L. et al. (2005). The effects of urban spatial structure on travel demand in the United States. The Review of Economics and Statistics 87(3): 466-478

[8] Waka Kotahi NZ Transport Agency. (2014). BCA Strategic Options Toolkit [PDF, 1.2 MB] Second edition.