Roads Reimagined
Roads reimagined as vibrant & productive destinations in the city.
Image Credits: illustration from Soft City by David Sim, Island Press
Roads occupy a staggering 18 to 30 per cent of the total available land area in cities today (1).While these figures are for American cities, similar if not higher percentages could be expected in other countries as well. These numbers represent a significant proportion given that space is a scarce and intensely contested urban commodity. While roads have always been ubiquitous in the urban landscape, the 1950s saw a major shift in the impact they had on city planning. Private cars and motor vehicles, in general, began to define urban lifestyle since then. This translated to planning as cities began to be developed, and redeveloped to make way for the car. Roads took centre stage in cities and pushed the needs of its people and of Nature to the fringes.
Urban mobility is poised to undergo significant and seminal transformations yet again. While many of these changes will be necessitated by the immediate need to reduce greenhouse gas (GHG) emissions, a lot of the transformations will be enabled by innovations in technology—another pivotal transition in our lifestyles and its choices. Car-lite cities, walkable cities, drones, hyperloops, personalised mobility devices, liveability parameters, etc., are all significant trends and measures that will be shaping the future of our cities. With such scale of changes imminent, it presents an ideal opportunity to rethink how we value our roads in this future and what purpose they could ser
Repurposing Roads to Generate Clean Energy
Image 1: Illustration of Solar Canopies over Highways
Image Credits: LABOR3 Architektur GmbH - Switzerland
At present, road-based carbon dioxide (CO2) emissions account for 72 per cent of all transport related GHG emissions in the world—surpassing both air and sea-based transportation modes (2). In addition to emissions emitting from vehicles, there is also the sizeable quantum of embodied emissions already spent building these roads out of high-carbon materials like cement, tar and asphalt. A study done in the UK found the whole-life emissions for a 1-kilometre stretch of road to be between 2,658.9 tonnes of carbon dioxide equivalents (tCO2eq) and 880.3 tCO2eq, depending on the road category (3).
Soon, however, these same roads could instead be producing clean renewable energy that could power future electric vehicles (EV) as well as our cities and villages. Roads present an ideal surface for harvesting solar energy as they are often exposed and unshaded—particularly the expansive main streets and expressways, which are too wide to be shaded by tree canopies. Various stakeholders including governments, research bodies and industry players have been experimenting with this idea to produce clean energy in their countries.
Some of these ideas are in their incubation stages, being tested and engineered for deployment. An example is the proposal developed by the Austrian Institute of Technology, Fraunhofer ISE, and Forster Industrietechnik (4). It is similar to image 1 above, with the intent being to erect solar canopies across wide highways.
There are also proposals that are already functional, like the one in South Korea where the central median of an entire road has been covered with photovoltaic panels. This road stretches for 20 miles between the cities of Daejon and Sejong. It generates enough electricity to power the streetlights and the EV-charging stations along this road whilst shading a cycling track below (5).
Image 1: Illustration of Solar Canopies over Highways
Image Credits: LABOR3 Architektur GmbH - Switzerland
The team from Farunhofer ISE estimated that if their model is deployed over the 13,000-kilometre-long highway network in Germany, it could potentially generate around 9 per cent of the country’s power demand (6). Students of the Integrated Sustainable Design programme at National University of Singapore (NUS) looked beyond just the width of the roads at several other components of the road transport system including car parks, bus depots, covered pedestrian walkways, etc., alongside Singapore’s MRT infrastructure. The students considered only certain parts of the road network to avoid harming existing tree canopies and other green spaces. Their concept study estimates solar energy production equivalent to almost 1 to 6 per cent of Singapore’s current energy demand.
There have also been other ideas with a similar intent using piezoelectric panels and PV panels embedded in the road surfaces. Although these have shown potential, their initial runs have also revealed shortcomings and challenges that will need to be overcome (7).
Reclaiming Roads as Shared Public Spaces
Image 3: A Parklet reclaims part of a busy street in Philadelphia
Image Credits: Shiftspace
Several cities across the world have been appropriating roads to return them back to the realm of the people as shared common spaces. Examples of this abound from Montreal, Philadelphia, Manhattan and Amsterdam to Milan, Barcelona, Bogotoa and Singapore.
Such actions are of particular significance in high-density urban settings where public spaces have often ceded their existence to either the demands of vehicular traffic or to lucrative commercial developments. Yet, such shared spaces are vital urban elements that provide much-needed breathing space to residents. The COVID-19 pandemic further demonstrated their urgent need in cities.
The act of reclaiming the streets, however, will have to go beyond simply dieting roads and appropriating space. These spaces will have to be adjusted to make them fit for use by the people.
Most existing streets in cities were designed solely to accommodate as many lanes of cars as possible; they were never designed for humans. Thus, they do not conform to our scale. As humans, we tend to prefer more enclosed and intimate urban spaces (8) (9). Designers must therefore be creative in the use of simple urban elements to produce engaging environments for the pedestrians. These elements could include street furniture, plantings, graphics, signages, lightings, etc. These are all simple everyday elements, capable of profound impact when designed cohesively. The importance of these soft features is depicted in the book titled Soft City authored by David Sim, a former Partner and Creative Director at Gehl. In this book, Sim shows how such simple, banal features can make urban streets more attractive and more liveable—encouraging a multitude of connections and encounters (10) .
The images below juxtapose contrasting street images from two cities. One shows an urban setting consumed with expansive roads that discourage any pedestrian realm. The other shows one where the street has been reduced to the human scale, encouraging active use by pedestrians.
Redrawing Roads to Insert Nature
Image 4: Juxtaposed images of conventional roads (L) splitting urban neighbourhood vis-à-vis pedestrianized streets with trees connecting communities (R)
Image Credits: Shutterstock
It is not just shared public space that is needed. Cities also benefit tremendously with the insertion of green natural spaces. Reclaiming streets for community goes in tandem with the integration of greenery and Nature.
Such green spaces/corridors/nature ways have traditionally been limited to the periphery of the city or to areas of lower density—like suburbs. The ideas of people like Frederick Law Olmsted who advocated the creation shared green spaces in the heart of cities were not largely adopted even after the success of his projects, which included the Central Park in Manhattan and the Emeral Necklace in Boston.
The integration of green nature ways into the streetscape aligns to the notion of scale mentioned earlier. Once reclaimed, existing roads are often too wide for the comfort of pedestrians.
While urban design elements do reduce the street to a more intimate scale, the remainder provides a perfect opportunity to insert green strips and pockets to further reduce the street to the human scale (9) whilst also endowing numerous other benefits from having Nature in the midst. These range from lowering urban heat index, reducing noise and air pollution to that of improving the visual performance and overall liveability of the street.
The Spanish city of Barcelona has always been cited for delivering liveability amidst its high density—characterised by its iconic grid-iron pattern and a low-rise urban form. Part of this has been due to urban features like Las Ramblas-styled streets, which are largely pedestrianised, resplendent with lush green trees and abuzz with myriad activities—adding verve and conviviality to the urban life.
Yet, in the past decade, Barcelona, like many other cities, has also seen a rise in traffic congestion and a consequent increase in air pollution. Barcelona’s proposed solution to this is to implement the concept of Superblocks (Superilles in Catalan) (11). Each superille will comprise nine existing city blocks within which traffic will be reduced to only slow-moving local transit. This shall allow a lot more of the existing streets inside the city blocks to be pedestrianised and increase the quantum of nature ways.
Rechannelling Water through Roads
Image 6: A Green street project in Paso Robles, California
Image Credits: Cannon Corporation
Green streets can also serve critical hydrological functions. Over the years, the impenetrable surfaces of roads and other urban developments have blanketed much of a city’s true ground. This has almost obliterated the capacity of the ground to absorb storm water. The consequence has been rapidly depleting ground water levels in cities, causing scarcity and the increased occurrences of floods as storm water run-off have no natural buffers to detain and channel the flow. Such occurrences are only being compounded by ever more erratic weather patterns.
Yet, these same roads, if designed with the necessary green infrastructure, can instead help to slow, filter, and cleanse storm water run-off from the impervious surfaces of the city. This will greatly reduce the risks of floods and water loggings and improve ground water recharge. These green streets can be created by replacing part of the streets’ asphalt/concrete with bioswales, vegetations (perennials, shrubs, trees), soil and engineered systems (permeable pavements), which can perform the said hydrological functions.
Several cities across the world have already been implementing these measures—though on a limited scale and confined to certain streets. These include Seattle, Portland, Auckland (12) (13), etc. Green street designs are also finding their way into urban development codes and guidelines. This will encourage a larger scale implementation of such features that are needed in many cities across the world.
A Road to Positive Impacts
The collective potential for impact from streets that are reimagined to be productive vibrant, green spaces is tremendous. There are already estimates, both speculative and measured, of such impacts.
On the one hand are tangible outcomes like ecological services rendered. For example, in Vitoria-Gasteiz, in the northwest of Barcelona, where the Superblock concept has been piloted since 2008, has already shown continuous improvements in performance with respect to air pollution levels, noise levels and increase in car-free areas available for public use (11). Tangible benefits also extend to financial and social parameters. Studies in New York found a 49 per cent drop in commercial vacancies in pedestrianised zones. Similarly in Mexico City, pedestrianisation led to a 30 per cent increase in commercial activity and a 96 per cent reduction in crimes. Similar results have also been found in studies done in UK and other large cities (14).
Then there are also the intangible benefits that contribute to the strengthening of the city’s social and symbolic capitals. Reimagined and repurposed streets will promote social independence—where the interests of the human and Nature shall no longer be subservient to that of the car and commercial interests. Transformative reimagination of streets has the potential to make them into epicentres of public life and networks of growth and productivity. Streets, as the famous Danish urbanist Jan Gehl comments, could become destinations in themselves.
However, a lot needs to be done beyond these acts of design and planning. Translating these ideas from the drawing board to large scale city-wide projects require tremendous work, cost and above all else - the buy-in and participation of multiple stakeholders, particularly, the people. Getting such stakeholder participations has often been the Achilles’ heel of these projects.
In multiple instances, projects to reclaim roads for community and Nature have often faced stiff resistance from one or many stakeholder groups. These new ideas are often perceived to be unwelcome disruptions to the business-as-usual status quo. The Cheonggyecheon* restoration project in Seoul is a good example of the initial resistance put up by nearby business owners who were apprehensive that removing the road would mean a demise of their businesses. However, it was the prudent advocacy of the then mayor and his foresight that the project overcame these challenges and managed to convey the potential value it would bring to the stakeholders. Today it’s a remarkable success story that designers, real estate developers and policy makers alike refer to.
Showing tangible results is an essential part of winning support of stakeholders. While overseas examples can be useful, pilot projects are what must be actively used to this end. According to Gehl, it is important to show people and stakeholders what life could be like and thus ignite their imaginations.
The other equally critical factor to realizing road reclamation projects successfully is the need to provide robust and efficient distribution of public transportation facilities that will complement efforts to reduce private car ownerships. This is a critical part of the puzzle in several cities, particularly in the developing countries where public transport is inadequate and often struggles to keep pace with rapid urbanization. This in-turn compels residents to rely more on private transport which in-turn creates an even greater demand for wider roads – thus creating a vicious cycle.
Yet, change is imminent and necessary. Whatever maybe the context, the future of transport is headed for significant changes around the globe. It is imperative that we seize this opportunity to transform the drab grey road infrastructure that exist today, into ones that could become the vital nerves of the city in more ways than they are at present. They could soon be pulsating with social life and natural splendour whilst producing clean energy, sequestering carbon, and cleaning and retaining valuable rainwater. The benefits are still serendipitous and will continue to be discovered as we go on to reclaim our roads.
Image 7: Streetscapes of the future
Image Credits: image courtesy for FXCollaborative
Footnote
* The Cheonggyecheon project was an urban restoration project in Seoul, South Korea. It removed a highway overpass that had covered the Cheonggyecheon river for decades. The project led to the daylighting of the river and ushered in swathes of vital blue and green public spaces into central Seoul. This project has been studied by several scholars to understand and measure the impact it has had on several indicators including higher real estate values, improved qualities of public spaces and natural environment etc.(15)
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