Roads, railways, pavements, buildings, streets, towns, cities slums and suburbs all fall with the broad definition of urban sprawl. Like a long concrete sheet billowing into the horizon you only have to take an international flight over a big city to see just how vast the problem of urban sprawl can be.
And the problem is only set to grow as cities around the world continue to expand, a process of urbanisation that sprawls concrete, pavements and roads over woodland, farmland or green belt areas. With an additional 1.2 billion people expected to migrate to urban areas by the year 2030 (that the equivalent of a city the size of London being transported into an urban area), humanity is undergoing a transformational shift into urbanisation that will change the face of the planet.
Urban sprawl definition
Urban sprawl is the process of uncoordinated urban growth which often accelerates the expansion of towns and cities in an unsustainable way. It is usually a consequence of lower density of buildings, in terms of population, in urban areas characterised by residents who have high levels of car ownership.
Urban sprawl also means a higher level of energy requirements, more water consumption and higher levels of traffic, pollution and congestion.
The OECD defines some of the key drivers or urban sprawl and outlines in a thorough report and the context in which it arises:
Urban sprawl is driven by demographic, economic, geographic, social and technological factors. These include rising incomes, preferences for living in low-density areas, natural barriers to contiguous urban development and the technological progress in car manufacturing.
Most importantly, sprawl is also policy-driven. Maximum density restrictions, specific zoning regulations, tax systems that are misaligned with the social cost of low-density development, the underpricing of car use externalities and the massive investment in road infrastructure contribute to this phenomenon.
A large urban footprint also means less space for wildlife and the manicured lawns of the suburbs and congested highways of large modern cities have little in the way of hiding space for wildlife to survive.
Research published in the journal Nature has found that the focus of urban sprawl has largely been skewed towards wealthy countries in American and Europe where the definition of urban sprawl has very different characteristics to the urbanisation taking place in developing[ing countries such as India and Brazil.
With up to 72 percent of the studies monitoring diversity loss as a result of urban sprawl in wealthier countries the devasting biodiversity happening in developing countries has largely been overlooked.
As more people move to cities as a result of the process of industrialization, wealth creation and more opportunities cities themselves must keep expanding, within a finite amount of space, to keep up with the rapid growth of their populations.
Urban expansion is a reality that will continue to grow over the next century. The question for urban planners is how to build cities that can respond to climate change in a way that improves the quality of life for their residents.
How can urban sprawl evolve to meet the challenges of climate change?
The Intergovernmental Panel on Climate Change (IPCC) has produced an in-depth investigation in their report Climate Change and Land which a comprehensive assessment of the current ways we use land and a stark warning that links deforestation, urbanisation and unsustainable development to drought and rising temperatures.
The report summarises thousands of research papers and was produced in collaboration with hundreds of scientists around the globe. It outlines the dangers in proceeding with our current scale and method of urbanisation and indicates that a significant transformation in our approach to urban sprawl needs to be implemented in order to avoid the most catastrophic effects of climate change.
Whilst reducing our carbon emissions should be a priority it’s also clear this the IPCC’s report and the scientific research of countess scientists and environmental organisations around the world that humans must change our relationship with the land, sea and air.
How we do that has implications for urban planners worldwide but if we don’t build our priorities into the design and planning stages of our urban areas, and retrofit our existing cities to make them more environmentally friendly than the consequences of not doing so could be catastrophic.
Urban sprawl options and alternatives
Cities and large urban areas have approached the climate issue by implementing policies that reduce carbon emissions within their localities. However, in order to be sustainable cities need to look beyond their borders to consider all of the resources they suck in from around the world.
To measure their complete ecological and carbon footprint they need to implement carbon-free alternatives to everything that is involved in the provision of food, clothing, water, products and resources to our urban centres.
This means cities need to completely reassess how the way they operate and how their influences extend way beyond the city limits, exerting influences that have climate-damaging consequences right around the globe. Cities will need to ensure food is provided from sustainable sources of agriculture and products consumed to not end up contributing to massive land-fill waste deposits.
A low carbon urban infrastructure
Railway systems, underground tube lines, electric buses, bicycles, electric scooters and electric car-sharing schemes are forging ahead in cities around the world as societies, and companies, completely and radically rethink how to reinvent the transportation of billions of people around the world.
Companies like Uber are working to provide services that will directly compete with public transport whilst providing a complete start to endpoint transport service. They, along with the likes of Google and Tesla, plan to roll out fleets of electrically powered autonomous vehicles which will offer direct-to-destination rides of their customers at incredibly low prices.
The ability for customers to ride-share, furthering reducing costs, and the advantage of being delivered directly to their final destination, as opposed to a central station terminal, means the companies like Uber will have a distinct advantage over public transportation, which on price (and many other factors) will be unable to compete.
Urban transportation can be green and the technology exists to implement sustainable transport across all of transportation sectors. The politics of each city and town around the world will determine how quickly that is scaled up to provide a meaningful solution for city commuters.
High-density green infrastructure
High-density housing can often suggest cramped, living conditions in over-crowded urban areas that are not environmentally friendly but allowing planners to build apartment blocks that provide many more families with space to live over a smaller area is in fact a much more environmentally friendly planning process than building acres and acres of suburbs.
This approach will ultimately lead to more compact cities, bringing inhabitants closer to their places of work. It also discourages the use and ownership of cars and encourages residents to cycle or walk. Denser development also physically stops the concreting over of landscapes that might provide environmental benefits by absorbing carbon. Natural areas like forests, peatlands, and wetlands.
Though standards for green buildings vary, they are generally designed to use less energy and water and improve the indoor environment, including air quality. The most widely used certification for green buildings is called LEED (Leadership in Energy and Environmental Design).
And producing this in-depth infographic to show just how buildings can be designed to facilitate a greener way of living.
Barcelona, Spain is a city with exceptionally high levels of density and yet urban planners have found ways to make their city a very liveable urban space that helps to reduce its impact on the environment.
In an ambitious programme that protects the ability of citizens to navigate the city, the Barcelonan authorities have outlined their goals online:
- A dynamic, diverse Barcelona open to the world where people can get around the whole city easily and efficiently.
- Focusing on protecting pedestrians and easing the co-existence of different uses. On foot, by bicycle and on public transport. The best options to travel the streets safely and sustainably. Equitable mobility within everyone’s reach. Smart and respectful to the environment and people.
- Barcelona is heading towards fume-free sustainable mobility.
- The world’s big cities must reduce greenhouse gas emissions as part of the fight against climate change. Because we cannot let the way we get around affect the future of the planet or the generations to come. For the right to get around. For the right to a healthy city.
Additionally, Barcelona is working to free up to 60% of the cities streets from the grip of the personal car to turn them into “citizen spaces”. This radical approach can be best illustrated in the film below from StreetFilms and it’s one that urban planners around the world should consider when it comes to transforming their own public spaces.
Is there a place for nature in urban spaces?
It might be easier to think that given the vast oceans of concrete and asphalt we’ve dumped on the planet, about 1 million sq km as estimated in 2010 almost double the size of France, there’s not much room leftover for nature.
And in many urban areas, you’d be right. Our inner-city landscapes are dominated by soaring buildings, street-lights, vehicles, roads and concrete interspersed with the occasional tree. You’d be forgiven for thinking that finding nature in some urban environments might be a bit like trying to find a needle in a haystack.
Nature can survive, and thrive, in urban spaces and urban spaces can be adapted to help facilitate the natural process. There’s even a name for it: Biophilic urbanism. This is defined by the following characteristics according to Springer Link:
Biophilic urbanism is based on the knowledge that humans have an innate connection with nature that should be expressed in our daily lives, especially in cities. This has not been a strong feature of architectural principles (even though there is a long tradition of landscape architecture), yet potentially it offers great rewards if it is implemented in the structure of the built environment.
And there’s a growing movement in biophilic cities that are inspiring urban planners and residents around the world to adopt a more nature-friendly approach and one that provides innumerable benefits to their residents. This movement has evolved in the Biophilic Cities network. Across the network and it’s members:
These partner cities are working in concert to conserve and celebrate nature in all its forms and the many important ways in which cities and their inhabitants benefit from the biodiversity and wild urban spaces present in cities. Biophilic Cities acknowledges the importance of daily contact with nature as an element of a meaningful urban life, as well as the ethical responsibility that cities have to conserve global nature as shared habitat for non-human life and people.
Singapore is one such member city that is leading the way in a number of ways to protect and restore nature within its city areas. It has ambitious plans to be the world’s greenest city and work is underway to ensure developments are green. The government there plans to restore its mangrove areas and plant thousands of trees to supplement it’s existing two million trees, 350 parks and 4 nature reserves.
In addition to providing additional habitats for wildlife, trees will help cities protect against deadly heatwaves in the future that would otherwise be exacerbated via the urban island heat effect. Trees have countless other influences that can benefit our lives and our surroundings:
The movement towards greener, more environmentally aware, nature-friendly urban spaces is growing. C40, a global network of cities committed to combating climate change:
C40 Cities connects 94 of the world’s greatest cities to take bold climate action, leading the way towards a healthier and more sustainable future. Representing 700+ million citizens and one-quarter of the global economy, mayors of the C40 cities are committed to delivering on the most ambitious goals of the Paris Agreement at the local level, as well as to cleaning the air we breathe.
Urban sprawl is a reflection of the rapid transformation of human populations from a rural way of life into the urban environment. With that come economic prosperity, improved standards of education, health and, for the most part, an increase of wealth that benefits individuals moving into highly populated urban areas.
Yet this comes at the expenses of the climate, the environment and the natural spaces that once thrived where cities now dominate. The trend towards urbanisation is irreversible and the evidence shows that, as a species, most of us will, now and in the future, find our homes in cities and urban spaces around the world.
The tension this creates is clear: how do governments persuade their citizens to care about the environment and it’s increasing fragility when an urban way of life is ever more cut off from nature? The answer seems just as clear: create spaces for nature to thrive, build and design developments that are green at every level and enable people of all ages to maintain a relationship with nature that benefits humans, wildlife and the environment we all share.