10 reasons to depave your city

Near my Luton office there’s a junction that scores highly on the unnecessary paving scale. It’s out the back of the mall, so there’s a vast blank wall above it too, a concrete landscape with no room for life. Nature being what it is, it makes use of every nook and cranny regardless, but it’s a space that has had the possibility of life deliberately designed out. As far as the planner was concerned, nature in any form would be an inconvenience here.

There’s a place for convenience and hard flat surfaces, of course. But I suspect you can think of places where you live that are unnecessarily barren, sealed up in concrete and asphalt. Here are ten reasons to depave such places and set them free.

1. Reduce urban heat – one of the best ways to reduce the urban heat island effect is to plant trees and increase vegetation. They absorb heat rather than bouncing it back at street level, and they provide shade.
2. Carbon emissions – Lower urban temperatures mean lower cooling costs and lower carbon emissions. Trees and green spaces also act as carbon sinks, absorbing CO2 from all the traffic and human activity in the city.
3. Biodiversity – nothing stamps on biodiversity like unnecessary paving, whether that’s plants, insects or bird life. Opening up the soil and planting trees and shrubs can create new habitats, encourage pollinators, and bring life back above and below ground.
4. Reduce flooding – stormwater runs off hard surfaces quickly, risking overwhelming drains. Green spaces and rain gardens hold and soak away water much more slowly, reducing the risk of blocked drains and flooded streets.
5. Air pollution – green spaces capture and filter dust and airborne pollutants. A hectare of mixed forest can collect 15 tonnes of particulate matter from the air every year.
6. Water pollution – when rain water runs off concrete or tarmac, it sweeps soot, dust and other pollutants into the drains, and then into watercourses. These could have been absorbed and processed in the soil. Instead, they end up in rivers, damaging aquatic life.
7. Health – if we’re reducing pollution, we’re improving health. Asthma and respiratory diseases are directly linked to airborne particulates, which are known to be reduced by trees in urban environments. Psychological benefits matter too. Access to green space and a sense of connection to nature are important aspects of wellbeing.
8. Place-making – blank, concrete urban spaces are not places people want to visit or spend time in. Opening them up and planting them values them as places, makes them distinctive, and fosters local pride. If you depave and replant as a community initiative, rather than just petitioning the council to do it, it will be all the more effective.
9. Economics – Reducing air pollution and respiratory diseases saves on healthcare costs. Creating more distinctive places has a role in regeneration and attracting investment. And of course, you can depave and create urban farms if you’re looking for more direct economic benefits.
10. Aesthetics – Concrete is boring. Trees and flowers are pretty. This is reason enough to dig up unnecessarily paved areas, and don’t let anybody tell you otherwise.

There’s more I could add, about how green spaces can abate traffic noise, how trees can serve as windbreaks, disperse light pollution, or how they reduce that hot, acrid traffic smell you get in cities. We could talk about the links between attractive, safe green spaces and antisocial behaviour. Or how more walkable cities might coax more people out of their cars and encourage them to walk instead, increasing physical activity and reducing obesity. But really, how many reasons do we need?

If you’re ready to buy a pinch-bar and get cracking, here’s a guide to depaving to get you started (pdf). You might want to look up Depave, an organisation in Oregon that facilitates depaving, and Depave Paradise in Canada. I’m not aware of any equivalents in Britain, but if you know one – drop me a link in the comments below.