Proximity: The Key to Sustainable and Accessible Cities

In an enlightening talk at Mobil.TUM 2024, Dr. Cecília Silva , Assistant Professor at the Faculty of Engineering, University of Porto (FEUP), explored the concept of proximity and its far-reaching implications for cities, mobility, and accessibility.

View the full talk on YouTube: https://youtu.be/NEII3C_fO8Q

Understanding Proximity

Proximity has become a central theme in urban planning, often discussed through the lens of the “15-minute city” or “human scale city.” Although these terms have gained traction recently, the idea itself is not new. According to the Cambridge Dictionary, proximity means being near in space or time, encapsulating both physical and temporal closeness. These aspects are important for effective urban planning.

Proximity-centered accessibility prioritizes having essential services and amenities within a short distance, thereby minimizing the need for extensive travel. Conversely, mobility-centered accessibility focuses on the ability to travel quickly to reach these services, irrespective of distance.

The Challenge of Speed

A significant point addressed was how speed undermines proximity. Over the past few decades, urban planning has focused on increasing travel speed through the construction of highways, high-speed trains, and other infrastructure. While these measures have reduced travel time, they have also inadvertently encouraged urban sprawl. As people find it easier to travel, they often move to areas with lower proximity to services, becoming more reliant on mobility solutions.

Urban dispersion occurs when people live in areas without nearby amenities because they can travel quickly to access them. This trend has led to the concentration of services in fewer locations, such as large shopping malls, rather than being dispersed throughout neighborhoods.

Impacts on City Dynamics

The negative feedback loop hypothesis illustrates how mobility-centered accessibility reduces the value of proximity. As cities focus on enhancing travel speed, they inadvertently decrease the accessibility of services within walking or cycling distance. This cycle increases dependence on high-speed travel, undermining the concept of proximity that many urban planners aim to achieve.

Practical Examples and Risks

Ongoing projects mapping 15-minute city practices have found that nearly 100 cities worldwide are implementing policies to enhance proximity. However, the level of commitment and variety of these policies differ significantly. Some cities have successfully integrated measures to reduce speed and improve local accessibility, while others still prioritize mobility, hoping to achieve both goals simultaneously. This dual approach often fails to deliver the desired outcomes.

The Suburban Challenge

Suburban areas present a significant challenge to achieving proximity. These areas, a product of mobility-centered policies, rely heavily on fast travel to access services. As cities continue to expand their suburbs, the distance between people and essential services increases, exacerbating the problem.

Conclusion

Proximity is crucial for creating sustainable, accessible, and equitable cities. However, achieving this requires a shift from prioritizing speed to focusing on closeness. Cities must recognize that increasing travel speed often undermines proximity and should instead invest in creating environments where essential services are within easy reach. By doing so, cities can enhance social, environmental, and economic well-being, ensuring that urban spaces are livable and resilient for future generations.

View the full talk on YouTube: https://youtu.be/NEII3C_fO8Q