Everyone’s talking about the need to create more housing. Is there any space left over for commercial real estate? What are the challenges urban planners must address to create spaces that are truly mixed-use? The editorial team at zoOM spoke with Hamburg Chief Planning Director Professor Jörn Walter, and councilor for urban planning, Cornelia Zuschke (Düsseldorf), on topics ranging from outdated laws – which limit the ability for functional mixed-use space to develop in cities – to the “city of the future”
What would your ideal urban city look like?
Walter: I find it difficult to describe an “ideal city.” There are so many individual factors influencing it – I’d prefer to focus on the concept of urbanity. Urbanity arises where people and businesses come together. An urban city is a vibrant, diverse city, one that encourages a high density in terms of social interaction, economics, and physical space. Diversity and proximity unleash creative forces.
Zuschke: Seen abstractly, the city is an ideal structure that can evolve through the power of its combined potential and take on current challenges. In other words, the ideal city is a holistic city. All areas of life – working, living, culture, recreation – need to be interwoven into living structures. This mixture arises from the city’s understanding of itself – it’s intrinsic to the city, so to speak. I believe in this model of an integrated city and total, constantly evolving urbanity.
Let us talk about individual districts within a city, can you name any successful examples?
Walter: The first place to look for examples is southern Europe, where there is a tradition of cities with small-scale mixed use. But there are also successful examples of urban areas to be found in German city centers – such as what was built before the First World War. It’s only after the Second World War that we start to see divided and therefore monotonous cities. Urban planners are currently making an effort to bring these functions together once more.
Zuschke: Cities such as those that emerged during the Middle Ages, as models that featured every function and therefore shaped our culture, are good places for us to link ideas of functional diversity and public space. In those days, construction was extremely dense. Düsseldorf also displays some of this patchwork of functional components. Though it emerged from industrial areas with residential areas around, the city continues to fill in the missing links bit by bit.
At the moment, however, one still has the impression that it’s all just about housing, leaving no space for businesses.
Walter: Yes, you might get that impression. That has a great deal to do with politics, however, and with what will ostensibly get a more positive reaction in the public sphere. But the demand for more housing and urban growth automatically also bring with them a demand for workplaces close to urban centers. This is why urban planners will continue to focus on mixed use. In Hamburg, for example, we gave equal consideration to housing and urban production in our design for the “Stromaufwärts an Elbe und Bille” [Upstream on the Elbe and Bille Rivers] project.
Zuschke: It’s somewhat typical of German Gründlichkeit [thoroughness, rigorousness] for us always to focus on answering specific issues and analyzing them carefully while losing our sense of the big picture. It’s no longer possible for us to stuff the variety of urban functions into segregated forms and areas of urban development. We’re forced to retroactively try to fix the consequences of this segregation through mobility and infrastructure – and are then somehow surprised when we can’t. We’ve reached the limits of what is technically possible in terms of mobility, and if we continue to separate living from working, the problem will only get worse.
Is there an optimal weighing of residential, office, commercial, retail and recreational space?
Zuschke: What is optimal is whatever suits the place itself in a robust way. Robust urban structures guarantee that cities retain their adaptability. We must be able to cope with changes without constantly having to redesign plans and establish or abolish new bureaucratic and legal norms.
Walter: Achieving a balance between various uses is absolutely something to strive for. The necessary space ratio must be considered for each city on an individual basis. Every city means something different to its region it is in. It has its own specific situation and connection to public transportation, its own commercial structures and position on centrality indices – in other words, its own value as to how attractive the city is to retailers. Our land-use plan in Hamburg, for instance, determines 70 percent of all building zones for residential buildings, while offices and commercial use only take up 20 percent.
What do you think of the new category “urban area”?
Zuschke: It signifies a leap forward in how people are thinking about the issue and is emblematic of a paradigm shift. But in terms of detailed content, there’s still a lot to do.
Walter: Many issues are still unresolved, such as the legal aspects of noise levels: For example, a distinction is still made between commercial and traffic noise, but that’s utterly out of touch with reality. When a truck is driving down the street, it’s permitted to be louder than when it’s turning into the driveway of a company. That simply doesn’t make sense.
Does that mean that more laws need to be changed or supplemented?
Walter: Yes. We have to discuss the categories of use determined by German ordinance on land usage (BauNVO), about the German federal immissions control act (BImSchG), and urban density values. Take the classic core business zone (MK) as defined by the BauNVO: City centers are usually MK zones. People are only allowed to live in city centers in this category in exceptional cases. Is that really what we want? When I engage in dialog with citizens, I hear a different story. They would like to see lively downtown areas.
The basic problem: The BauNVO divides the city into categories in order to separate commercial areas from residential ones. This principle of division is a consequence of pollution from the era of industrialization. But industry and production have changed since then. Think of the Ruhr area. In those days, the sky was black with pollution. Thanks to advances in technology, modern companies cause very few problems that can’t be solved. “Logistics equals noise, and industry equals pollutants” – the situation has turned out to be much more differentiated than this perception. Logistics develops new forms of mobility, industry and production generate much lower emissions, and – not least due to digitization – these things are much more compatible with urban life than in the past. This opens up completely new possibilities for the reintegration of business enterprises in the city.
The BImSchG is also a product of the 1950s and 1960s. The possibilities for protecting residential areas have improved considerably since that time – for instance, thanks to extremely effective active and passive measures for noise control. It’s no longer the case that for each new residential building, a business enterprise must be forced out.
By the way, all of this is also a key topic for trade associations that could take on a much more active role and encourage the creation of new commercial space.
Zuschke: I agree with everything Professor Walter just said. To expand on these ideas, we should also reconsider the ordinances of breakdown. Does the Seveso Directive have sufficient jurisdiction to create truly good neighborhoods between commercial and residential areas? And also: The wording of the Environmental Impact Assessment in Section 13 (a) of the German Federal Building Code (BauGB) – a section that was actually intended to speed up urban-planning processes – delays the process even more. In a formal sense, we’re “de-bureacratizing” ourselves, but in terms of content, we’re still loading ourselves down with another issue. I’m just thinking about the highly complex structures of the building codes for individual federal states and cities. Supposedly these have been formally liberalized, but with regard to content, more and more questions need to be legally resolved through expert appraisal. This is a burden on planners and developers alike.
In your opinion, for Hamburg and Düsseldorf respectively, what is the role of commerce in the city and in downtown areas?
Walter: A major one – with local peculiarities based on the city’s history. In the 19th century, what was then the Gängeviertel – an area of densely packed alleyways and tenements – saw the development of an incredibly high concentration of residential buildings, interspersed with small-scale businesses. After the outbreak of a major cholera epidemic [due to a lack of clean drinking water – Ed.], these buildings were gradually demolished. In the aftermath, Hamburg began to develop as an administrative center for the region.
Following the trend of the 1960s, 1970s, and 1980s that kept city functions separate, the HafenCity was one of the first major inner-city projects in Hamburg to have the goal of an integrated land use: The project’s intention was to create a close-grained vertical and horizontal mix of residential and working areas – an efficient use of space with relatively high density, right in the heart of the city. Varied and small-scale – this continues to be our strategy for Hamburg.
Zuschke: Here in Düsseldorf, there have been countless conversions, expansions, and restructurings. To name one example, a new residential area has been emerging near the Central Station that borders on an industrial area and the most intensive traffic hub in the city. The goal is to retain the commercial sites such as forwarding companies and industrial metal-processing facilities on Vogelsanger Weg and let the residential buildings grow around them. For this project, we plan on using “milestone stages”, each of which functions separately. This is also a learning curve for us: Does it even work, or do we have to reassess the situation again?
Bringing together living and working, and the availability of educational institutions and recreational facilities, all in combination with a strong, robust infrastructure stabilizes the community. It keeps society balanced. Until now, we’ve been focusing on the division of functions as well as the “shopping city” or “entertainment city”. We’ve paid less attention to what’s unexciting, to what’s ordinary and mundane – the challenge of creating a link between living and working. As the councilor for urban planing, this is precisely what I am responsible for. I get excited about every area that is multifaceted enough to require the mingling of commercial and other urban functions with residential spaces.
How do you imagine the city of the future – let’s say 50 years from now?
Zuschke: In the city of the future, we will be under less stress due to improved integration – because “working” and “being at home” will have melted together into one category, “living.” Change will be seen as something positive. Less space will be taken up, because the city will mainly grow inwards, becoming – in a positive sense – more dense: This means that in addition to dense neighborhoods, there will also be plenty of space to live in. Options for lifelong learning will bring people of all ages together. Despite its high density, the city will still have an outstanding concentration of high-quality space. People will enjoy being out in public and walking the streets; gone will be the areas where people were once afraid to go. The landscape for mobility will have been completely transformed, with more freedom and flexibility. I don’t mean that in an ideological sense. I trust in innovation and people’s ability to choose what they want for themselves from a variety of options. I also hope that, 50 years from now, the trees being planted now will have grown as tall as those currently being sacrificed due to construction.
Walter: There will definitely be a great deal of mixing. The city will be significantly more environmentally friendly, greener, with mobility that doesn’t harm the environment and great recreational options.
There’s no doubt in my mind that we will be able to address population and economic growth in a sustainable way: We still have immense resources in cities that can be developed into denser, more diversified urban centers. Certain business clusters can only evolve in a kind of exchange and only to a certain density. This also reduces land usage and prevents new green and agricultural areas from being sealed over.
Both of you sound very optimistic...
Walter: I truly am. The 21st century can, must, and will be the century of mixed use in cities! Simply put, monolithic structures are the wrong approach. As urban planners, it is our job to reunite different uses. New technologies are doing their part. Businesses will continue to evolve and consistently use cleaner and cleaner energy. Our relationship to mobility will change. In the future, the car will be less of a status symbol and more of a utilitarian tool; “owning” will take a back seat to “using.” Overly pedagogical measures will not be necessary to effect changes that significantly improve the quality of life in cities.
Zuschke: Normally, we tend to focus far too much on the problems. I see change and development as a gift and a chance to overcome our differences and work together. But if I could make a plea for just one thing: Cities need much more support during this time of changes to mobility. There’s this attitude that keeping the air clean and noise levels low – meaning a dwindling quality of life – are urgent problems for communities alone to deal with. But these are problems not just for communities, but for all of us. The most important thing is for us to live in a healthy way. In Germany and all around the world. So the only path forward for city planning is one we take together, fully integrated.