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Science: Urban planning and design for sustainable cities

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May 29, 2020

Future cities have to be more sustainable to deal with limited resources and climate change. ETE scientist Ilse Voskamp is analysing energy and water use in Amsterdam. In addition, she is identifying key factors influencing consumption of these resources. This knowledge forms a scientific basis for landscape architects and urban planners to design sustainable cities.

Cities are hotspots of consumption and waste production. Consumption of resources like raw materials, food, water and energy is increasingly concentrated in urban areas. Nowadays cities even consume about three quarters of global material and energy supply. These resources are not only used by residents and industrial processes, but also to operate and maintain an extensive infrastructure of electrical networks, sewage systems and drinking water treatment facilities. At the moment, already more than half the world population is living in cities and urbanization is still ongoing, putting extra pressure on limited reserves and the earth’s ecosystem. Therefore, more sustainable city designs are needed to safeguard reliable resource supply, avoid resource depletion and the continuing destruction of the natural world. So, urban planners and designers need science-based information for different, sustainable and climate-robust city designs, where resources are efficiently utilized and recycled.

Evidence-based decisions

Worldwide there are thousands of cities that have expressed their ambitions to become more sustainable. These cities also have in common that they expect to have a substantial growth. The city of Amsterdam is one of them: more than 50.000 houses are planned to be built in the coming 15years. This is an excellent opportunity to design more
sustainable residential areas. But before starting resource-conscious building projects, information regarding so-called ‘urban metabolism’, is crucial. This term refers to all resource flows into and out of the city. Voskamp: ‘A city is almost like a living organism or an ecosystem, where there’s input of all kinds of resources like building materials, food, water and energy. On the other hand, there’s also output like waste, waste water and CO2 emissions. A sustainable city closes cycles by smart reuse and recycling, similar to what happens in a natural ecosystem.’ Information regarding resource flows can help planners and designers to make evidence-based decisions for making cities more sustainable and work towards circular urban metabolism.

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Fig. 1. Schematic representation of linear vs circular metabolism.

Crucial data


Currently, information regarding urban metabolism, including resource flows like energy and water, can be generated using a so-called material flow analysis. This method helps to understand and to quantify all resource input and output from a city. ‘Unfortunately, the data collected using this method are not detailed enough and are therefore not suitable yet to help urban designers’, Voskamp says. ‘It gives information about resource use in the whole city, but lacks crucial data on use in individual city parts.’ In  addition, designers need to know underlying reasons for a low or high resource use of particular residential areas, which is currently not provided by this method. For instance, a high energy and water use can be due to the type and age of a house and the presence of a garden. Also, the type of consumer is important and water and energy consumption patterns can also be a reflection of a household size or income level. According to Voskamp, this type of information is crucial to (re)design residential areas sustainably.

Smart choices

Urban metabolism is not only influenced by consumers and house types; also changes in society play a role, the scientist found out. For example, increased economic growth, and a consequent higher standard of living of the residents, may result in more water and energy use. Therefore, to make smart choices for a sustainable design, it is essential to know the group of residents and their specific needs first. ‘Different consumer groups have different preferences’, Voskamp explains. ‘Factors regarding age, income and household size determine what type of house fits a specific group, while at the same time these factors influence water and energy use.’ Depending on the kind of residents, fundamental choices have to be made regarding house and garden size, atmosphere in the neighborhood, green areas, and infrastructure. The challenge for the designer is how to integrate all this within a sustainable design. A larger house with a garden could result in higher water use for irrigation and energy use for heating. But at the same time, a large house has more room for solar panels on the roof, while more space around the house enables the residents to recycle or harvest rainwater on their own property. Also, a garden allows a better water drainage after extreme rainfall, making such an area more climate-proof. But the same could also be achieved by integrating more, green public space in the area. Voskamp: ‘So, having this level of detailed information regarding consumer characteristics, resource use, and the possible coherence, is important for designers and planners to better understand resource flows. This helps them to eventually come up with resource-conscious solutions and improvements in their designs that fits different consumer groups.’

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Artist impression of the future ‘Bajes Kwartier’ in Amsterdam.

Future vision


According to Voskamp, a sustainable design of neighborhoods in the city also requires strategic sustainable planning, a future vision how you want Amsterdam to be in 50 years’ time. This vision is also needed to match the choices made for residential areas with this vision for the city as a whole. Voskamp: ‘What are the desired type and size of houses, and what possibilities do they offer for a resource-conscious design? To what extent is there the possibility to implement renewable energy technologies and recycling on larger properties, for example in industrial areas, instead of residential areas?‘ Eventually, for Voskamp a sustainable Amsterdam is much more than just optimizing resource flows and recycling: ’It is also about livability and resilience to a changing climate, where dealing with more extreme heat and rainfall in the city will be important issues’, she says. ’In the future, I envision a sustainable Amsterdam that is part of a much larger sustainable ecosystem.’ 

This research is part of the Urban Pulse II research project under the auspice of the Amsterdam Institute for Advanced Metropolitan Solutions (AMS). In Urban Pulse, academic, societal, and industry partners aim to acquire an understanding of the spatial and temporal dynamics of resource flows in Amsterdam.

Selected publications


Voskamp, I.M., Sutton, N.B., Stremke, S., & Rijnaarts, H.H.M. 2020. A systematic review of factors influencing spatiotemporal variability in urban water and energy consumption. J. Cleaner Prod. 256: 120310. https://doi.org/10.1016/j.jclepro.2020.120310

Voskamp, I.M., Spiller, M., Stremke, S., Bregt, A.K., Vreugdenhil, L.C., & Rijnaarts, H.H.M. 2018. Space-time information analysis for resource-conscious urban planning and design: a stakeholder-based identification of urban metabolism data gaps. Resour. Conserv. Recycl. 128, 516e525. https://doi.org/10.1016/j.resconrec.2016.08.026