Let it rip: Why countries around the world are rolling back roads
Streets and lots are being stripped and re-greened to tackle the urban heat island effect, redirect rainwater and reverse the idea that we must build to develop
Like money and passports, we take them for granted. We’ve forgotten there was ever a world without roads.
Well, parts of the world are rolling back the tarmac.
In the US, UK, Australia, Belgium, France, Italy, China, Spain and Poland, citizens’ groups, NGOs and municipal corporations are working together to depave and deseal, prying off asphalt and concrete and restoring the natural surfaces of streets, parking lots, school yards, driveways, even domestic backyards.
That’s step one. “What comes next is crucial: restoration of the soil, which has often been polluted and artificially compacted,” says Marc Barra, an ecologist with the Regional Agency for Biodiversity in Paris, part of France’s Institute of Planning and Urban Development. “This is done through ecological engineering techniques including decompaction, the incorporation of earthworms and the use of pioneer plants.”
Since 2020, parts of schoolyards and college quadrangles have been stripped in southern France and turned into rain gardens (a sunken garden designed to allow rainwater to seep through), in efforts led by the local administration and the NGO Bleu Versant, but executed with the help of teachers, parents and children.
In Belgium, a hotly contested race between towns is seeing under-utilised roads, parking lots, driveways and backyards depaved and re-greened in a similar fashion, since 2023. It was a devastating flood in 2021 that got the local administration thinking about depaving, and they have been working with residents since.
In London, the mayor’s office offers a free online toolkit on how to strip and regreen concrete in one’s driveway or backyard, or set up community groups to do this on a larger scale in the neighbourhood.
In Melbourne, there is talk of turning half the on-street parking slots into sunken rain gardens to combat flooding, with trees to add shade and mitigate the urban heat island effect as well.
Environmental factors such as hotter and drier summers, the heat island effect, recurrent floods and depleting groundwater levels are driving such efforts.
“Depaving helps make over-concretised cities spongier,” says Thami Croeser, an urban planning researcher with Royal Melbourne Institute of Technology (RMIT) University, Australia.
It is important to monitor success by carrying out flora and fauna inventories and measuring benefits such as cooling, seepage of rainwater and the use of the space by local residents, Barra adds. “It’s also important to recycle the bitumen, in the spirit of the circular economy,” because the carbon footprint of producing those materials is far too high for them to simply be disposed of.
So, in Belgium, “tile taxis” have been commissioned by the local government, to ferry away bits of tarmac and loads of gravel, which is then processed and recycled.
Meanwhile, in Portland, Oregon, where it all began, block parties are helping residents approach depaving as something to celebrate, rather than a doomsday measure or a chore.
Roads not taken
Depaving can be traced to a small localised effort in Portland in 2008, when an NGO called Depave worked with the city administration and local residents to strip the tarmac off a single vacant lot near a café, and turn the space into a permaculture garden.
The Fargo Forest Garden is now home to fruit and nut trees, berry shrubs, a vegetable patch, and so many birds that it is also a magnet for bird-lovers.
Before Depave and Oregon, in the 1970s, the US Forest Service began mapping unused roads in national parks and restoring them to their natural surfaces. Many of these had been built around the logging industry, and were no longer in use. Yet they were contributing to landslides and disrupting wildlife.
Re-routing
Of course, not all roads are villains. In our world, shaped as it is, they play a vital role. They save lives, keep neighbourhoods and nations safe, and ease the movement of goods and people.
In order to determine whether a road ought to stay or go, it helps to start by asking: Would local residents really miss this one, if it weren’t here, says restoration ecologist Adam Switalski, who consults with the US Forest Service on their road-decommissioning projects.
“Climate change is pushing us to adopt nature-based solutions and reimagine our cities,” says Croeser of RMIT University.
Depaving, in this context, represents a vital social movement of our time. “It is, after all, also a symbolic action — an admission that we can and should step away from the idea that we must build in order to develop,” says Barra.
Increased funding would help, he adds. It could be the difference between the movement remaining rather niche, and it growing into a mass global campaign along the lines of Reduce, Reuse, Recycle.
“We’ve centred so much of our urban hubs on automobiles and concretised, built-up spaces that these elements are often all we see, smell and hear,” says Croeser. “But streets are really just spaces between buildings and they can be anything we want them to be. So we need to change the rules and say: How about we don’t do asphalt here anymore?”
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TOUR EFFORTS ACROSS THREE CITIES
Perma-change in Oregon
In Portland, Oregon, block parties are held to discuss depaving.
Amid music, art and food, residents talk about what stretches of concrete they don’t really need, and decide what they could use the space for instead.
In 2022, one such effort saw an unused parking lot in Portland turned into a traditional Native American healing space complete with a ceremonial area, sweat lodge, fire pit and a garden home to hundreds of native plants, including ceremonial tobacco.
In videos on the Depave website, residents speak of how proud they are to have been able to help build it, and how good it feels to hand it over to a generation that has no lived experience of such a space.
It was the NGO Depave that drove that transformation, and has driven similar efforts here since. Back then, it began by holding talks with citizens, a landowner and the city administration to turn a vacant concretised lot into a permaculture garden.
Once the go-ahead came from both sides, a date was fixed and people were invited to join in. About 148 citizens turned up at the lot: authors, ecologists, entrepreneurs, teachers, students, social workers and seniors. They yanked the asphalt off with pry bars and then scooped up the gravel that lay underneath. There was some singing and the beating of a drum.
A year later, seeds were planted. Today, the Fargo Forest Garden is home to native fruit and nut trees, berry shrubs and a vegetable patch.
The NGO Depave works on two types of projects in the state: “transformations” and “retrofitting”. The former alters a site’s usage entirely, as with the healing space and permaculture garden. Retrofitting projects tend to be smaller, and involve scraping tarmac off parts of streets, lots or yards to install tree wells or small patches of soil and greenery that can generate shade, allow water to percolate, and help reduce flooding.
The NGO says it has depaved about 35,000 sq metres of concreted land in these two ways, since 2008.
“We also train those interested in starting such efforts,” says communications coordinator Katherine Rose. “The idea is to turn as many lifeless paved areas as possible into permeable spaces that are more useful to the communities they are situated in.”
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Stars in their eyes, in Belgium
Neighbourhoods across the Flanders region of northern Belgium are in a race to depave.
In the city and suburbs of Leuven, for instance, residents are meeting to discuss which stretches of road can be stripped down to their soil and lined with indigenous trees. For every sq metre converted and for every action (depaving, greening or collecting rainwater from roofs), a neighbourhood earns stars.
Collect enough stars at the local level, and the city administration throws a pizza party or organises a garden concert. Top the list at the regional level, and there are prizes up for grabs every month.
“At the moment, the city of Leuven ranks third in the Flanders race,” says Baptist Vlaeminck, coordinator of Life-PACT (People-driven: Adapting Cities for Tomorrow), an initiative of the Leuven city administration.
The contest is designed to be fun, but the larger mission is more serious.
Since 2021, the Leuven administration has been promoting depaving as a way to help mitigate flooding, tackle the urban heat island effect and replenish groundwater levels.
“The year 2021 was a tipping point,” Vlaeminck says. “Parts of Leuven were inundated more severely than anything local residents could remember. Similar floods elsewhere in the country claimed lives. A lot of people realised then that climate change wasn’t some years away. It is our current reality and we need to act now.”
The year after that flooding, Leuven reached out to the tiny suburb of Spaanse Kroon (250 housing units; about 500 residents) to ask if they would help with an experiment to reimagine the neighbourhood’s roads.
To start things off, the administration created a landscaping popup in one corner of an under-utilised street, to offer residents a glimpse of what could be.
Next, a gardening-themed “information market” was organised, where residents had a chance to talk to local representatives and experts about what depaving would entail.
Public meetings and workshops followed, including some that included children. Residents discussed the kinds of trees and shrubs that might be planted, and how parking needs and road safety would be managed.
Then work began. Some streets were made narrower; sidewalks were converted into greened earth. Unused or under-used parking spots were mapped out and earmarked for depaving. Once the asphalt was off, landscaping followed.
A key part of the project involved motivating people to also depave private spaces such as driveways and backyards. To help them do this, the administration offered free appointments with “garden rangers” for advice. And it offered “tile taxis”, which could be called to pick up the slabs of concrete once they had been removed.
“These tiles, as well as cobbles and gravel, are then cleaned and sold for reuse,” says Vlaeminck. (This kind of reuse is a crucial step, environmentally, given the massive carbon footprint involved in creating these materials.)
Earlier this year, the city of Leuven calculated that it had depaved over 4,000 sq metres of concrete roadways, sidewalks and parking spaces (in addition to scores of private driveways and backyards).
That’s plenty of points added to the Leuven score, and Leuven is aiming to win the regional contest. “We want to increase our count,” Vlaeminck says, “and we want to motivate people, not just to win but also to make their city more liveable.”
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“No sign that we were ever there”
“Historically, roads, because they are economically crucial, have been indiscriminately built in the US, with little consideration of their environmental impact, especially in ecologically significant areas such as forests and river basins, where logging is a major industry,” says restoration ecologist Adam Switalski.
These roads have, over time, contributed to soil erosion and increased rates of storm run-off, worsening landslides, polluting streams and rivers, and affecting terrestrial and aquatic wildlife, he explains.
By the 1990s, many of the roads built around logging weren’t even in use, but the environmental damage they caused continued.
So, for 20 years, Switalski has been working to roll some back, advising on road-decommissioning projects particularly around streams and rivers in US national parks and forests.
His biggest joy, he says, is to return to a site and see… nothing at all; just a landscape continuing as if undisturbed. As the plants come back, so does the wildlife. “It’s so rewarding,” he says.
A road by a river, depaved in the early 2000s, even helped fish flourish. In a 2007 habitat study published in the journal Transactions of the American Fisheries Society, researchers noted that road decommissioning resulted in vegetative regrowth, reducing fine sediment in streams, driving the populations of bull and cutthroat trout up in the Flathead National Forest.
“When you see something like that, it means we did something right,” Switalski says.
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Put it in park: Melbourne
Imagine Melbourne with trees in place of streetside parking slots.
A study by ecologists, architects and urban planners with the universities of Melbourne, Sydney, Monash and California, led by the Royal Melbourne Institute of Technology (RMIT) University, indicates that the depaving and redesign of about 11,000 on-street parking spaces (about half of total street capacity in the city) would reduce water pollution, capture more of the rainwater that otherwise floods the city and is wasted, and draw more birds and bees back to the city.
Perhaps most significantly, it could help battle the intense 40-degree-Celsius-plus heat waves that have been becoming more frequent in Melbourne in recent years — if the former parking lots were replaced with trees, shrubs and spongy sunken garden beds designed to allow rainwater to percolate.
Findings were published in the journal NPJ Urban Sustainability in 2022.
Where would people park? The study addresses that too.
It turns out that of the approximately 220,000 parking spaces in the Melbourne municipal area, most are off-street and residential or commercial. And apartment parking has a vacancy rate of 26% to 41%.
“There is potential to reallocate much of the on-street parking to these vacant off-street lots,” says Thami Croeser, urban planning researcher at RMIT and lead author of the report.
Using Geographic Information System (GIS) data provided by the City of Melbourne, the researchers confirmed that this kind of reallocation would be possible, if motorists were willing to park and then walk, on average, 100 to 200 metres.
Stripped of concrete, meanwhile, the former parking slots would collectively amount to 60 hectares worth of new tree canopy in the centre of the city, where much of the heat is typically trapped. “It would also lead to the interception of millions of litres of rainwater that could tackle flooding, and improve the quality of water since soil helps filter out pollutants,” Croeser adds.
The research has garnered a lot of media attention, partly because it offers a roadmap for key goals that the city of Melbourne has set for itself, which include increasing tree canopy cover from 22% to 40% by 2040.
“It’s scary for politicians to take space away from cars, especially in busy cities like Melbourne or Mumbai. Drivers can be hysterical and it can be dramatic,” Croeser says. “But we aim to keep the pressure up and hopefully get policy-makers to take note of the impact that simple measures, implemented on available land, can have. Because the reality is that this is a positive trade-off.”
