On the international vitality of urban spaces
Prof. Kenworthy, as Professor at Frankfurt UAS, you focus on sustainable cities in your research and teaching. What sparked your interest in this subject area?
It’s difficult to say what ultimately sparked my interest in this topic. I think it was being nurtured already during my early childhood. We never owned a car. I lived in the inner suburbs of Perth, pretty much as a “freewheeling” child. I would ride my bike, catch tadpoles and tortoises in the nearby wetlands – and we took buses and trains on longer trips. To mingle with other people and add the spice of variety, my mother and I would take the train on weekends. I had a deep-rooted sense of what a sustainable city should be. My studies ended up being something of a launching pad for shaping and cultivating my interest in sustainable cities.
You spearhead the academic debate with an international perspective. How does the concept of sustainability vary across different countries and cultures?
Sustainability is the interaction of environmental, economic and social factors for the concurrent improvement of each factor. It’s not about making a tradeoff or striking a balance between the different factors. Cities in the more affluent corners of the world are aiming to reduce not only their resource consumption but also the waste generated by this consumption while simultaneously improving their quality of life. In less affluent countries, resource consumption is far less wasteful than in the US or Australia and is in fact very low compared to other countries. In poorer countries, there is extensive justification for increasing resource consumption to meet basic human needs such as adequate food supply, shelter, education, healthcare and so forth.
How successfully has sustainability been implemented in Germany to date, and in which areas are even stronger efforts and initiatives called for?
One aspect that really floored me when I first came to Germany was the stark contrast in terms of the quality with which houses are built in Germany compared to Australia. As a general rule, the bulk of houses in Australia are wafer thin. In hot or cold weather, the inside temperature will rapidly approach the outside temperature. Large amounts of energy are needed to either heat or else cool Australian homes. In Germany, by contrast, residential buildings are pretty much the exact opposite of what you find in Australia.
On the other hand, preferences for passenger cars continue to be a big draw in Germany – led by three of the world’s best known manufacturers and with no speed limit on the autobahns. We are incessantly preoccupied with electric mobility in private transport with the notion that we might somehow convert our entire fleet of vehicles from diesel and gasoline to electric and that this would ultimately solve the whole transport sustainability problem. It’s a trap – and we must do everything in our power to avoid falling into it. It’s simply an illusion. Germany already has more than 500 passenger vehicles per 1,000 inhabitants. The best future is one in which cars take their place alongside all other forms of mobility as opposed to being the transportation option of choice.
All cars, regardless of their drive system, take up space. Roads and parking lots must be constructed. Envision a future in which streets look like a green network of public spaces – where our pedestrian and bike mobility needs in the social space outside our front door were at least on a par with vehicle drivers’ entitlement to streets and parking space. Throughout urban history, streets have always had the function of being first and foremost a social space.
Will students graduating from Frankfurt UAS possess the depth of knowledge needed to be good ambassadors of sustainability?
My students most definitely will – as will those of my colleagues!
Let’s take a look at the academic subject areas. Why do compact, mixed-use cities tend to be more sustainable than others?
Until 1850, the old compact “walking cities” were a common sight the world over. A compact city has a dense concentration of population, as well as other facilities and amenities, that can service most residents’ needs locally – either on foot or by bike – coupled with access to well-functioning public transport services for longer trips. Less land consumption for loose urban sprawl and less extensive transportation infrastructure for cars – such as expressways and parking lots – translates to more protection not only for green spaces such as woods but also for peri-urban and inner-city food production. The irony is that dense European cities provide far more nature-based solutions and green infrastructure than do sprawling metropolises in the US and Australia, which have allowed their green spaces to vanish beneath asphalt and home expansions. And the more greenspace, the fewer heat islands we have and the better it is for cooling a city. Because urban temperatures sometimes soar to alarming levels and the number of heat-related deaths is increasing, it will be vital to provide the most natural cooling possible for cities. As our cities absorb vast amounts of energy, water, food and even people and cars from great distances every day, they produce huge quantities of waste and, environmental pollution.
Is there a chance that cities might be consumers and producers of energy, food and clean water at one and the same time?
Yes, there are abundant opportunities to generate renewable energy in cities by installing photovoltaic and solar thermal systems on roofs or building facades. In a closed-looped recycling system, concomitant waste materials are upcycled into a sustainable source of resources. Wastewater can be easily treated to meet safe drinking water standards – and that using not only traditional wastewater treatment but also biological systems. Under the industrial food production system, today’s cities are consumers of foods that have clocked up thousands of “food miles”, which means that tremendous quantities of energy are embedded in their production and delivery – the proverbial “three-thousand mile Caesar salad.”
What creates a high-quality public space and a vibrant public culture?
Cities are public spaces. With the degeneration of a city‘s public culture, we find a prevailing tendency towards inward-looking self-segregation among its residents. One of the many US cities that have guarded, gated communities is Los Angeles, which is sometimes referred to as “Fortress LA” and “the Ecology of Fear.” These cities have public spaces that are largely unattractive and offer ample opportunity for crime in that there is no critical mass of people or of public activities to provide natural surveillance and a sense of security through social control mechanisms. This is sometimes described as “private splendor, public squalor.” Cities that linger in people’s memories are typically those that teem with life, color, interaction and multifaceted opportunities to gain a variety of experiences. Barcelona is known for La Rambla; Munich, for its Marienplatz and Karlsplatz pedestrian zones and also for its English Garden; New York, for Central Park and Times Square; London, for Covent Garden and Oxford Street; and Paris, for the Champs-Elysées.
Is democratic decision-making a sine qua non for all-round sustainability?
Sustainability, especially in cities, can really only be achieved where there is a shared vision of the future backed by general consensus. This unavoidably includes the challenge of attempting to capture, accommodate and respect the diversity of opinions manifested in each city, and from there to forge ahead step by step, monitoring and assessing the progress made towards achieving these goals, which at least a majority of the population will have adopted as their own. It sometimes happens – when converting streets into pedestrian zones or introducing “traffic calming” – that a number of former detractors come to realize in the end that this change has been good for business, and more often than not the owners of these stores that had not been involved in the street conversion knock on the mayor’s door and ask for the changes to be extended up to their store.