Urban Sustainability

Challenges to Urban Sustainability

To understand the need for urban sustainability, we must first explore the challenges facing cities. Most cities in the world are growing, especially in less developed countries. This is due to natural increase and rural to urban migration, the movement of people from rural areas to urban centers with greater access to jobs and services.

Suburban Sprawl and Urban Growth

With increasing urban centers, demands for housing, healthcare, schools, and other services also increase. To remedy this pressure, cities have encouraged suburban sprawl or suburbanization, unrestricted growth design outside of major urban areas with separate designations for residential, commercial, entertainment, and other services. Suburban growth is a quicker alternative to resolving issues of urban growth and affordable housing. This is because the land is cheaper outside of cities, with fewer restrictions on construction and design.

However, major issues arise with too much suburbanization. Since most housing is built outside of cities and away from businesses and other services, commuting times increase, particularly in the US. High car dependency is linked to greater air pollution, as carbon dioxide (CO²) and other particulate matter are emitted from vehicles. With a lack of public transport, walking, or cycling options, many people in the US rely solely on cars to complete even short trips. Despite cheaper land costs for building homes, higher energy consumption, sprawling highway and roads, and pollution indicate that uncontrolled suburbanization is not a sustainable urban design model.

Suburban development in Colorado Springs, CO

Urban growth, whether within cities or in suburbs, can also lead to a loss of parks, agricultural fields, and green spaces. By reducing these sites, the effects of climate change can also be exacerbated, particularly when it comes to major environmental catastrophes. By removing vegetation, areas are not only more susceptible to floods, but also animal and plant extinctions.

With a greater concentration of populations in cities, the ecological footprint of cities remains higher than smaller towns or rural areas. An ecological footprint is a measurement of the impact one person's activity has on natural resources. Combined ecological footprints can indicate how many resources it takes to support society and the economy. Naturally, with more people in one place, the total ecological footprint can appear very high. However, taken individually (per capita), city residents emit and consume less than their suburban and rural counterparts. This is because city residents tend to live in smaller accommodations, drive less, and share more resources.

Urban Sustainability Initiatives

Urban sustainability initiatives serve to remedy the challenges cities are facing. Urban sustainability initiatives focus on improving the economic, social, and environmental conditions for residents in ways that minimize negative effects on the environment. This is primarily driven by urban development and planning projects.

Sustainable Urban Planning

Urban planning is the design and regulation of a city's infrastructure and transportation. This is usually done at the local political level, where planners and designers are hired by authorities that are voted in. Planners and designers must do their best to reflect and balance the political, economic, and social interests of a city in their projects.

Sustainable urban planning or sustainable urbanism is a way of planning a city that reduces suburban sprawl; promotes active mobility and public transit use; and increases green spaces and use of renewables. Support for urban sustainability can be traced back to the New Urbanism movement, an urban design movement focused on creating walkable and environmentally friendly neighborhoods.

Sustainable Urban Development

Some major sustainable urban development projects include mixed-use development, transport-oriented development, and green building construction. What does this look like in a city? Let's dive into some urban development projects through the lens of urban planners.

Mixed-Use Development or Mixed Land Use

Mixed-use development is a planning style that mixes residential, commercial, entertainment, and other services together on the same block, street, or neighborhood. Imagine you leave your home and are able to walk to a grocery store a two-minute walk away, or can see a movie at a cinema that's just down the street. Successful mixed-use development requires density, so homes and businesses need to be in proximity to promote walking, cycling, and public transit use.

Fig. 2 - An example of mixed-use development design in Kirkland, WA; stores on the first floor and apartments above

Transport-Oriented Development

Transport-oriented development is a planning design that aims to tie mixed-use development with public transportation. In other words, a bus, tram, or metro station stop serves as the center point for building highly-dense mixed-use development around this. This promotes both dense mixed-use development, public transport use, and increased walking and cycling.

Green Building Construction

Green building construction or green infrastructure aims to conserve both energy and water resources by using them more efficiently. This is done by using sustainable building materials and design which reduce the amount of energy needed to power a building. One step further can include using renewable energy to power buildings. For a building to be more water efficient, conservation and recycling can be practiced. For instance, recycling greywater from rain runoff can be used to water local vegetation in the area.

Critiques of Urban Sustainability

Some critiques of urban sustainability planning and development are that initial investment costs are very high for governments, businesses, and residents. This is because renewable energy technology is still relatively new and costly, requiring a steep up-front expense. Public transportation is also costly, requiring greater taxpayer contribution to ensure long-term planning and maintenance. However, it can be argued that even without transitioning to urban sustainability, climate change effects will also be costly to clean up. With the increased frequency of environmental disasters, droughts, and energy insecurities, these problems will only continue to be exacerbated without greater intervention.

Urban Sustainability Examples

There are successful examples of urban sustainability all over the world. In these examples, different governments, agencies, private developers, and residents work together to ensure sustainable urban planning projects are implemented. Even after design and construction, residents and developers may request new changes, requiring prolonged participation from all members in the process.

Copenhagen, Denmark

Copenhagen was once a car-centric sprawling city, despite historically dense design within the downtown core. Since the 1990s, Copenhagen began tackling issues of traffic congestion and air pollution from car dependency. They did this by investing heavily into public transport options and prioritizing transport-oriented development and mixed-use planning. Further, they promoted bike use through expanded bike lanes. Currently, almost half of residents in Copenhagen cycle to work or school. As a result, air pollution has improved and car dependency has reduced drastically.

Wide bike lanes in Copenhagen promote safe bike use

Portland, Oregon, USA

Portland, Oregon is another great example of a city that has taken urban sustainability measures in recent years. Most of the energy that powers the city comes from different renewable sources. Portland is also one of the first cities in the US to produce a master plan for bicyclists and pedestrians, i.e. major infrastructure and design plans for walking and cycling. Transit-oriented development has also been a priority for ensuring residents can use local public transit to reach locations and services they need.