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SUSTAINABLE URBANIZATION

By 14 June, 2017February 24th, 2020No Comments

BY JACOB KUREK, PARTNER IN HENNING LARSEN ARCHITECTS & JAKOB STRØMANN-ANDERSEN, PHD STUDENT AT HENNING LARSEN ARCHITECTS.

Within a few years, over half of the population in Africa will live in cities. Rapid urbanization means environmental, economic and social challenges for Africa and the rest of the world. Sustainable cities and holistic planning are part of the solution to these global challenges.

In 1950, just 30 per cent of the world’s population lived in urban areas. Today it is over half. According to the UN’s global development programme, UNDP, the majority of the inhabitants of Asia and Africa will live in cities before 2020. This urbanization has taken hold in developing countries and there is a need to act if urban development in the world’s poorest regions is to be turned in a more sustainable direction. In 2015, the UN Member States adopted new global targets for sustainable development. The 17 development targets will include tackling climate change by 2030. Green transition and sustainable urbanization have thus become development goals and growth sectors for business. Given that 90 per cent of global urbanization is going to take place in developing countries, it is natural to centre on Africa in an attempt to outline the challenges and opportunities of future sustainable urban development. As architects and engineers, we have combined knowledge and experience of urban development in many different contexts. This article offers an overview of the current situation in Africa and a review of holistic urban planning as a tool in the development of a sustainable city. Through a description of the architect’s method and an example of sustainable urban planning, we will try to illustrate how the idea of a good city is not a universal model, but rather a premise or a range of instances to be adapted to the local context and culture. The interplay between the city and its infrastructure, buildings and their functions, and urban spaces’ design and activity are in fact the key to a good, sustainable city that is beneficial for its people and strengthens the culture.

Africa’s challenges – a review

Urbanization is a global trend. In the western world, cities are competing to attract the best brains and companies and to create the best cultural development so as to be at the forefront of the future. In large parts of Africa, however, urbanization has other considerations. Urbanization in Africa is, as was the case in North America and Europe in the 19th and 20th centuries, primarily driven by the quest for a better life. This means access to basic necessities like clean drinking water and good sanitation. The city provides access to health services, community and security that are not available in scattered, rural areas. Life in the city also allows for access to education and work, which in turn increases the chances of improving one’s economic situation. 62 per cent of the half billion people today living in Africa’s cities, live in slums. 27 per cent are without access to water, sanitation or electricity. Slums are characterized by monotonous, self-built constructions used exclusively for residential purposes. Endless rows of small houses and huts with no spaces, no vegetation and no variation. The remaining 38 per cent, some 190 million people, belong to Africa’s upper and middle classes. They live in well-functioning urban areas with paved roads, public transport, an efficient health system and cultural and educational institutions. In some cases, the slums extend right up to these urban areas but, in others, the border between rich and poor is sharply divided by the so-called gated communities. In slum areas, the inhabitants do not have access to the city’s communal facilities. Instead of access to training and work to improve the economic situation of the population, life in the slum offen leads to social problems, unhealthy living conditions, insecurity and less community. The burgeoning cities put great pressure on the planet’s environment. Today, urban areas occupy fve per cent of the earth’s land area but, according to The Global Environment Facility, account for two-thirds of the world’s total energy consumption and 70 per cent of CO2 emissions. As new cities rise in places not previously settled and existing ones grow ever larger, so the pressure on the environment increases.

The good city

The universal motivation for people to live in cities, is – according to the SwissFrench architect Le Corbusier, one of the most influential figures in contemporary architecture and urban planning – to help each other, to work together to defend themselves, comfort each other and attain the benefits offered by co-operation. Le Corbusier also had a universal approach to the city and believed that they should all follow the same structural model. Unlike him, we look for diversity and cities built in harmony with their unique local qualities. Cities can be the viable alternative to a population spread over vast areas of land. They have collective solutions to the basic logistical necessities, with urban density and infrastructure reducing the need for polluting transport, which consumes about a quarter of the world’s CO2 emissions. An apt example is the Danish ’Finger Plan’ of 1947, which is still relevant for the planning of the area around Copenhagen. The plan injects green wedges into the cityscape and divides the metropolitan area into smaller units. In the ’green fingers’ the collective community is planned in an infrastructure with S-train lines, roads and buildings in a mix of institutions, residential and commercial buildings. The Finger Plan is a testament to the long-term planning essential to the development of the good city. The city plan is a vision with objectives and desirables for several aspects of the city. It binds city elements – infrastructure, buildings and urban spaces – together. The city plan also helps to ensure that the city is built with a degree of diversity. The urban dynamic is an important part of the environmental and social sustainability. The premise for the good city is the same everywhere in the world. The good city is based on holistically planned infrastructure and buildings, which foster an active and rich city life. But a good city in Europe is not necessarily a good city in Africa. The local context, climate and culture should set the scene. Unfortunately, there are many bad examples in the Middle East, Asia and Africa, where the western city has been directly implemented with no local understanding of climatic and cultural differences. This has resulted in soulless cities and streets that undermine the local culture rather than enhance it; and create dead urban environments without city life.

The sustainable city as an alternative

We follow the same recipe in projects every time: we collect data and analyze the likes of sunshine, shade, wind and climate based on both qualitative and quantitative studies. An understanding of the place, its history and culture also comes into play. This allows us to ensure that the solutions we propose add value to what the place is about and to its specific setting; and create optimal growth conditions for urban life and the individual. In northern Europe, dark and dank corners are city life’s greatest enemy, while the sun and controlled wind conditions are a magnet for activity. In hot regions, such as the Middle East or Africa, shade and wind’s natural ability to ventilate are a prerequisite for being able to move around outside in the hottest and most humid months. Therefore, an in-depth study of the local climate is a necessary starting point to be able to model the city optimally and create a social, sustainable city with urban life and opportunities for individuals in the specific conditions. It is essential to consider the city’s structure and buildings in an energy and infrastructural context. In an urban area where the buildings are spread out, we look to address supply needs with a decentralized technical infrastructure, since it is not economically or environmentally sustainable to be tightly-bound logistically. In a densely populated area, a centralized technical infrastructure is an advantage. Cities comprise a combination of dense and sprawling buildings, and the task is therefore to optimize the two solutions and the interaction between them and integrate this in relation to the overall plan for the location of the buildings. Buildings have the capacity to create better conditions for each other relative to the sun, shade and wind. Research has shown that the effect of the urban fabric on a building’s energy consumption is far greater than previously thought. Optimization of the city’s structure is therefore a prerequisite for reducing the individual energy consumption of buildings. To reduce each building’s energy consumption is also a good idea in the long term in relation to climate impact. Part of our approach to design and building sustainability is that our designs are not only for today’s requirements. We build holistically oriented architecture that also strengthens the city for the future and makes it resilient with regard to its climate impact and the climate proofing of the city. On the African continent, this includes security against drought, storms and climate change and, in relation to the demographic development, which will place new demands on the city and its institutions in the future.

The city’s building blocks

In the Saudi capital, Riyadh, a new business district is on the way. It is a modern urban metropolis, which at first seems far removed from Africa’s rapidly growing megacities. Henning Larsen Architects has worked for ten years on this, which is the world’s largest sustainable urban development. The vision was to create a vibrant city space with activity around the clock. But because of the extreme temperatures of the desert, it proved to be a difficult challenge to create a comfortable microclimate that made life and a community possible throughout the city. As we see it, a city is not made up of unique individual buildings. It is a unified whole, and therein lies the quality. For example, by optimizing the buildings’ proportions and placement in relation to the local climatic conditions and through the use of light facade materials that reflect solar radiation back to the skies, it has been possible to lower the outdoor temperature of the Financial District by up to six to eight degrees compared to the surrounding city. The master plan includes many other sustainable initiatives that help both to optimize energy consumption and the comfort of the city. Despite the fact that Riyadh is located in the desert, work has also progressed on how the city could be a green area with vegetation and water. The heart of the financial district will be a transformed imitation of a Saudi wadi, which is a low-lying area in the desert that turns green after heavy rains. In the new district, the wadi will be an always green, shady and recreational area. The example from Riyadh is unique in the sense that the new financial district will be built on virgin ground, and it has been possible to plan every detail. Some cities in Africa will arise in the same way, but the vast majority will grow in relation to already existing urban areas; in the slums for example. The method for creating a better city is the same, however. It is also possible to create long-term strategies for the development of existing urban areas. In the African example, it is possible to imagine a strategy that, with smaller individual impacts, creates a great effect. It is necessary to look at buildings’ uses and functions. By mixing residential and business, there will be something with which to navigate the city. A small shop, a workshop or a green recreational space help to create the identity for a street or area. This may in turn help to create a larger, diversified urban structure. Public institutions are also good drivers of urban development. An open school can be used for education in the daytime and have other functions later in the day. Play areas and playing fields may be available, with school premises used for educational work, clinics, children’s events or administrative functions. It would therefore be invaluable to spend extra resources on educational and cultural institutions in the slums provided that they are designed and positioned in a way where they deliver benefits for as many as possible. Variation in the design of the city’s streets, roads and squares can improve micro-climate conditions. In a uniform street layout, light and shade are equally repetitive. In a street where the buildings’ facades are slightly offset relative to each other, there can be shady recesses and sunlight. This can be done by indicating the optimum street placement of new buildings in slum areas. It takes decades to implement urban development plans and build infrastructure such as power plants and distribution networks for modulated, centralized energy systems. Although this would be the most favourable solution in the long term, it is worth looking at alternative options. In many places in Africa, for example, it will be possible to create a functioning mini-grid based on solar energy.

Africa’s future

Over the next 35 years, the world’s urban population will grow by three billion people, predicts the International Organisation for Migration (IOM). This approximates to building a new city the size of Odense every single day. The quality of the new cities is, unfortunately, not directly comparable to Odense. They will arise, however, as either problematic mega projects or as self-built, disorganized urban areas where residents’ prospects for something as basic as sanitation and clean drinking water are slight. There is a need for global, long-term planning in relation to managing urbanization at an overall level with specific solutions, but also with specific guidance at ground level with the people who are seeking a better life in the city. Climate analyses, infrastructure, energy optimization and the overall planning of the city, the architecture, all build on the desire to create quality and a good life for the individual. There is no exact model that can be copied. The local climate and cultural, social and societal conditions should be regarded as co-players. The transparent, dialogue-based, holistic approach and the social dimension is what that we as Danish architects and planners can contribute in Africa and the world.

Jacob Kurek is an architect and partner in Henning Larsen Architects. He has worked on several major urban development projects outside Europe. Jakob Strømann-Andersen is a civil engineer and Ph.D. He is an expert in sustainable urban development and heads the department for Sustainability Engineering at Henning Larsen Architects.

This article was originally printed in the magazine Udenrigs that is published by The Danish Foreign Policy Society. This special issue on global urbanization was published in relation to the conference Urbanization and Exports that was hosted by Realdania and The Danish Foreign Policy Society