A sustainable city, urban sustainability, or eco-city (also “ecocity”) is a city designed with consideration for social, economic, environmental impact, and resilient habitat for existing populations, without compromising the ability of future generations to experience the same.
These cities are inhabited by people who are dedicated towards minimization of required inputs of energy, water, food, waste, the output of heat, air pollution – CO2, methane, and water pollution. Richard Register first coined the term “ecocity” in his 1987 book, Ecocity Berkeley: Building Cities for a Healthy Future.
Other leading figures who envisioned the sustainable city are architect Paul F Downton, who later founded the company Ecopolis Pty Ltd, as well as authors Timothy Beatley and Steffen Lehmann, who have written extensively on the subject. The field of industrial ecology is sometimes used in planning these cities.
What Is a Sustainable City?
There remains no completely agreed-upon definition for what a sustainable city should be or completely agreed upon paradigm for what components should be included.
Generally, developmental experts agree that a sustainable city should meet the needs of the present without sacrificing the ability of future generations to meet their own needs. The ambiguity within this idea leads to a great deal of variation in terms of how cities carry out their attempts to become sustainable.
Ideally, a sustainable city creates an enduring way of life across the four domains of ecology, economics, politics, and culture. However, minimally a sustainable city should firstly be able to feed itself with a sustainable reliance on the surrounding countryside. Secondly, it should be able to power itself with renewable sources of energy.
The core of this is to create the smallest conceivable ecological footprint while producing the lowest quantity of pollution achievable. All while efficiently using the land; composting used materials, and recycling or converting waste-to-energy. All of these contributions will lead to the city’s overall impacts on climate change to be minimal and with as little impact.
The characteristics of a sustainable city
The Adelaide City Council states that socially sustainable cities should be equitable, diverse, connected, and democratic and provide a good quality of life.
A sustainable city can feed itself with minimal reliance on the surrounding countryside, and power itself with renewable sources of energy.
The crux of this is to create the smallest possible ecological footprint, and to produce the lowest quantity of pollution possible, to efficiently use the land; compost used materials, recycle it or convert waste-to-energy, and thus the city’s overall contribution to climate change will be minimal if such practices are adhered to.
It is estimated that over 50% of the world’s population now lives in cities and urban areas.
These large communities provide both challenges and opportunities for environmentally-conscious developers. There are distinct advantages to further defining and working towards the goals of sustainable cities. Humans are social creatures and thrive in urban spaces that foster social connections.
Richard Florida, an urban studies theorist, focuses on the social impact of sustainable cities and states that cities need to be more than a competitive business climate; they need to be a great people climate that appeals to individuals and families of all types. Because of this, a shift to denser, urban living would provide an outlet for social interaction and conditions under which humans can prosper.
These types of urban areas would also promote the use of public transit, walkability, and biking which would benefit citizens health-wise but also be environmentally beneficial.
Contrary to common belief, urban systems can be more environmentally sustainable than rural or suburban living. With people and resources located so close to one another, it is possible to save energy for transportation and mass transit systems, and resources such as food.
Cities benefit the economy by locating human capital in one relatively small geographic area where ideas can be generated. Having a more dense, urban space would also increase people’s efficiency since they wouldn’t have to spend as much time commuting to places if resources are located close together, which in turn would benefit the economy since people can use this extra time on other matters; like work.
Practical steps to urban sustainability
These ecological cities are achieved through various means, such as:
- Different agricultural systems such as agricultural plots within the city (suburbs or center). This reduces the distance food has to travel from field to fork. Practical work out of this may be done by either small scale/private farming plots or through larger-scale agriculture (e.g. farmscrapers).
- Renewable energy sources, such as wind turbines, solar panels, or biogas created from sewage. Cities provide economies of scale that make such energy sources viable.
- Various methods to reduce the need for air conditioning (a massive energy demand), such as planting trees and lightening surface colors, natural ventilation systems, an increase in water features, and green spaces equaling at least 20% of the city’s surface. These measures counter the “heat island effect” caused by an abundance of tarmac and asphalt, which can make urban areas several degrees warmer than surrounding rural areas—as much as six degrees Celsius during the evening.
- Improved public transport and an increase in pedestrianization to reduce car emissions. This requires a radically different approach to city planning, with integrated business, industrial, and residential zones. Roads may be designed to make driving difficult.
- Optimal building density to make public transport viable but avoid the creation of urban heat islands.
- Solutions to decrease urban sprawl, by seeking new ways of allowing people to live closer to the workspace. Since the workplace tends to be in the city, downtown, or urban center, they are seeking a way to increase density by changing the antiquated attitudes many suburbanites have towards inner-city areas.
- Green roofs alter the surface energy balance and can help mitigate the urban heat island effect. Incorporating eco-roofs or green roofs in your design will help with air quality, climate, and water runoff.
- Zero-emission transport
- Zero-energy building
- Sustainable urban drainage systems or SUDS
- Energy conservation systems/devices
- Xeriscaping – garden and landscape design for water conservation
- Sustainable transport incorporates five elements: fuel economy, occupancy, electrification, pedal power, and urbanization.
- Key Performance Indicators – development and operational management tool providing guidance and M&V for city administrators
- Sustainable Sites Initiative or SSI, Voluntary national guidelines and performance benchmarks for sustainable land design, construction and maintenance practices. Key areas of focus are soil, vegetation, hydrology, materials, and human health and well being.
- The increase of cycling infrastructure would increase cycling within cities and reduce the number of cars being driven and in turn reduce car emissions. This would also benefit the health of citizens as they would be able to get more exercise through cycling.
- Educating residents of cities about the positive impacts of living in a more sustainable city and why it is important would increase the initiative to have sustainable developments and push people to live in a more sustainable way.
Buildings provide the infrastructure for a functioning city and allow for many opportunities to demonstrate a commitment to sustainability. A commitment to sustainable architecture encompasses all phases of building including the planning, building, and restructuring.
Sustainable Site Initiatives is used by landscape architects, designers, engineers, architects, developers, policy-makers and others to align land development and management with innovative sustainable design.
Some examples of sustainable architecture include:
- Eco-industrial park
- Urban farming
- Urban infill
- Walkable urbanism
- New Urbanism
- Individual buildings (LEED)
- Sustainable Sites Initiative (SSI)
A major focus of the sustainable cities, sustainable transportation attempts to reduce a city’s reliance and use of greenhouse emitting gases by utilizing eco-friendly urban planning, low environmental impact vehicles, and residential proximity to create an urban center that has greater environmental responsibility and social equity.
Due to the significant impact that transportation services have on a city’s energy consumption, the last decade has seen an increasing emphasis on sustainable transportation by developmental experts. Currently, transportation systems account for nearly a quarter of the world’s energy consumption and carbon dioxide emission.
In order to reduce the environmental impact caused by transportation in metropolitan areas, sustainable transportation has three widely agreed-upon pillars that it utilizes to create more healthy and productive urban centers.
The Carbon Trust states that there are three main ways cities can innovate to make transport more sustainable without increasing journey times – better land use planning, modal shift to encourage people to choose more efficient forms of transport, and making existing transport modes more efficient.
Some examples of sustainable urban transportation include:
- Car-free city
- Emphasis on proximity
- Diversity in modes of transportation
- Access to transportation
- Urban strategic planning
- Social factors of sustainable cities
What Should a City Be Like in Order to Be Considered Sustainable?
An ideal eco-city has frequently been described as one that fulfills the following requirements:
- An example of a green roof project.
- Operates on a self-contained economy that obtains resources locally.
- Is entirely carbon-neutral by promoting techniques like the use and production of renewable energy.
- Is established over a well-planned city layout that promotes walkability, biking and the use of public transportation systems.
- Promotes conservation of resources by maximizing water efficiency and energy efficiency, while managing an ecologically beneficial waste management system that promotes recycling and reuses to create a zero-waste system.
- Restores environmentally damaged urban areas.
- Ensures decent and affordable housing for all socio-economic and ethnic groups and improves job opportunities for disadvantaged groups, such as women, minorities, and the disabled.
- Supports local agriculture and produce.
- Supports future progress and expansion over time.
Besides these, each individual eco-city has an additional set of requirements to ensure ecological and economic benefits that may range from large-scale targets like zero-waste and zero-carbon emissions.
Some examples include the Sino-Singapore Tianjin Eco-city project and the Abu Dhabi Masdar City project. There are also some smaller-scale interventions like urban revitalization and the establishment of green roofs as seen in the case of Augustenborg, Malmö, Sweden.
The City of the Future
With the growing popularity of the concept, in the last few decades, there has been an exponential growth in the number of eco-cities established around the globe. Hopefully, we will see more of those in the next years.