Globally we are witnessing a wealth of experiments which aim to make streets more enjoyable for people. These experiments were happening before the crisis but the crisis has given rise to a veritable explosion in street experiments. Sometimes entire streets are converted into ‘streets for people’, where cars are no longer welcome and residents are given priority. So far, says Mobility and Urban Planning researcher Luca Bertolini, what has been missing is a good comparison between street experiments and lessons that we can draw from them in terms of systemic changes in urban mobility.

In the academic journal Transport Reviews, Bertolini compares a number of experiments and comes to the conclusion that policymakers should incorporate the successful aspects of urban street experiments into long-term plans and policy so they can understand them better and utilise them more effectively.

More and less radical experiments

Bertolini focuses on street experiments in which intentional temporary changes to street use are implemented to make ‘streets for traffic’ into ‘streets for people’. What are their main characteristics and impacts? How can these experiments trigger systemic changes in urban mobility? Bertolini compares experiments which are more and less radical:

• Changes to streetcrossings (re-marking of streets).
• The temporary transformation of a parking space by installing temporary seating, bike racks or public art (the re-purposing of parking spaces).
• 'Ciclovias' (in Latin America) and 'Open Streets' (in North America and elsewhere), whereby parts of streets or, the ultimate urban street experiment, entire streets are re-purposed.

Positive impacts

Bertolini concludes that analyses of these experiments indicate positive impacts on: physical activity; a shift of mobility away from the car and towards walking, cycling and public transport; increased safety; enhanced social interaction and social capital. It is also important that no negative impacts were found on local businesses. The positive impacts were, however, greater in larger scale experiments, which focused on re-purposing of the entire street. The often very short duration and low frequency of urban experiments also appear to limit the impact.

A framework to assess strengths and weaknesses

The positive impacts demonstrate the benefits of alternative street designs and purposes, says Bertolini, but their potential as triggers of a greater systemic change is unclear. He therefore proposes a number of assessment criteria, taken from the field of transition studies, which may help to assess and optimise the potential contribution to urban mobility change:

• How radical is the experiment? Are the interventions in the experiment fundamentally different from dominant practices?
• How driven is the experiment? Is it a step towards long-term change with the aim of resolving a social issue?
• How feasible is the experiment? Can it be achieved in the short term using available resources?
• How strategic is the experiment? Does it provide lessons in terms of how to achieve the intended fundamental changes? And do stakeholders have access to these lessons?
• How communicative and mobilising is the experiment? Does it reach and potentially mobilise the broader public?

Looking at the aforementioned street experiments, Bertolini sees potential strengths in their ability to be both radical and feasible, and in their ability to communicate and mobilise. Potential weaknesses are weak or non-existent links with urban policy and the lack of broad learning processes.

Proactively shape institutional and physical space for experimentation

‘If the potential of street experiments is to be utilised more effectively for urban policy, it is important that policymakers understand the various aspects of urban street experiments and their potential and limitations,’ says Bertolini. ‘The main challenge is not simply to tolerate street experiments but to proactively shape institutional and physical space for these experiments and to learn from them as a result.’