Renaturing cities: good for health and the economy
Would you enjoy a city full of parks, where streets were tree-lined, where cycling and walking were pleasant, a city with grass-insulated roofs on houses and public buildings to keep you warm in winter? According to a Eurobarometer study, there is an 84 percent chance that your answer is yes.
But you might be afraid that such a green city would mean giving up your car or experiencing a rise in the cost of living. The survey found that 28% of Europeans fear that natural areas would not be properly maintained, 22% expressed concerns over the high cost to the taxpayer and 18% feared rent increases due to higher property prices.
Urban planner Thami Croeser, spatial analyst at the RMIT (Royal Melbourne Institute of Technology), is studying what researchers call "nature-based solutions" (NBS), which means bringing nature back to the city to make the built environment a healthier and a better place to live. He is currently part of an international project team advising the European Union on planning for urban greening.
What can be done to convince people to give up their bad habits, for example concerning cars?
The thing is, people aren't actually the problem—it's how we work with people that makes them allies or enemies. Getting the community involved on these kinds of projects really early is one of the most important steps we can take. I have consistently found that even though many people do like their cars, they are willing to get creative to work out green solutions such as closing or narrowing a road, or giving up some parking space for green space or trees if it benefits their neighbourhood.
There will always be a few people who believe cars must be the priority at the expense of all else, but they are a minority, and most people understand that we can make really positive trade-offs once they're given a chance to engage in the process. The best thing is that urban greening isn't actually 'anti-car' at all. With clever design we can often retain some vehicle access while helping our streets get lots of trees, vertical greening and understorey planting.
But some might think that nature in cities is not that important after all, that if you like flowers and trees maybe you should go live in the countryside. What would you say to that?
Nature in cities does a lot of things for us. It can keep cities cool, prevent flooding, clean the air, improve our mental health and encourage exercise. It is also valuable habitat for many species, and can contribute to the beauty and identity of the places we live.
In my opinion, urban NBS are now more important than ever. As our cities get denser and busier, we get less and less contact with nature from private gardens and backyards. That means the public realm must increasingly be where we get the benefits of nature. This has historically been a 'blind spot' for city planners, urban designers and engineers.
As cities have developed, we've been focused on transport, housing, industry and infrastructure—nature has been an afterthought, as cities get a handful of parks and street trees at best. In the process, we have often produced very grey urban environments that get hot, flood easily and are unattractive and unhealthy to spend time in. We have a lot of retrofitting ahead of us, especially as the climate becomes more extreme. The good news is the NBS industry is maturing and there are more and more ways to help our cities go green.
Apart from the inhabitants, is there any resistance from the other stakeholders concerned in making cities more nature-oriented? What are the challenges with public institutions and businesses, and how is it possible to overcome them?
The big challenge is in getting institutions ready to deliver NBS at scale, this is a new task for most cities. This means that local governments seldom have the processes, design standards or laws to support NBS delivery. Internal departments might disagree on whether they are a good idea, and many NBS require the cooperation of other government departments. It can be hard work getting all the processes lined up, getting staff with the right skills, and building support across the organisation and with other institutions—but with these resolved, things can work a lot more smoothly.
In the EU project URBAN GreenUP we are looking at new financing models for green infrastructure, both within the community and within the business sector, and ultimately at the end of this project one of the big questions we have to ask is: how can we bring this to market and make products that people are actually going to go for? This vision of how to leverage private finance is a very central part of the project for us and I think that is rightly so. I have worked with local councils and we can do a lot of work in the public sector, but it's usually 25-30 percent of the market, the rest is private. If we don't learn to start leveraging the huge opportunities for green roofs, green walls, infiltration on structures, we'll only get part of the way, and we're going to get there pretty slowly.
What about the challenges faced by the three frontrunner cities (Valladolid, Izmir and Liverpool) of the URBAN GreenUP project? Could you give a couple of key practical examples of how you solved them?
Liverpool and Valladolid are really different cities, but both have dense central areas in need of more nature. I was really impressed that they have both managed to get large green walls into the central areas. Their efforts were pioneering in that they approached private building owners to negotiate how the plants would be installed, maintained and paid for. This is the kind of 'first time' stuff that is really difficult but it can be very rewarding when successful and replicated.
I am also delighted that both Izmir and Valladolid have been working successfully with their traffic departments to find alignments for green cycling routes. These not only help promote healthy modes of transport, but will also act as major areas for tree planting and urban nature. Again, it isn't easy to reallocate land to new uses and the teams have done good work to turn these major green routes into reality.
Is there a city or a neighbourhood in the world that you would present as an "ideal example" of NBS implementation?
I'd say 'ideal' is going to mean something different from city to city. The big shiny example that has impressed the world in recent decades is Singapore, both because it has hugely increased its tree canopy cover (while most cities have lost a lot of canopy), and because it has a lot of very impressive unconventional greening, like lush green walls and a floodable park. Of course, Singapore is in the tropics and its governance is quite unique, so its challenges, strengths and weaknesses likely won't be the same as those we face in Europe.
In Europe, I have been extremely impressed by the beautiful streetscape greening I saw in Amsterdam, especially because so much of it is from residents putting their own plants out into the streets. In Berlin, they excel at multifunctional parks and allotment gardening. Rotterdam is a world leader in green roofs. Barcelona is taking bold moves to reclaim street space from cars to turn it into public space. Depending on the challenges your city faces, any one of these approaches could be the ideal one for you.
By Selene Verri
Provided by iCube Programme