Check out the episode:
You can find the shownotes through this link.
Are you interested in the superblock model’s effects of health and the environment?
Our debate today works with the article titled Environmental and health effects of the Barcelona superblocks from 2025, by Katherine Perez, Laia Palencia, Maria Jose Lopez, Brenda Biaani Leon‑Gomez, Anna Puig‑Ribera, Anna Gomez‑Gutierrez, Mark Nieuwenhuijsen, Gloria Carrasco‑Turigas, and Carme Borrell, published in the BMC Public Health journal.
This is a great preparation to our next interview with Laura Reupke in episode 464 talking about the opportunities within the Superblock model.
Since we are investigating the future of cities, I thought it would be interesting to see how the Barcelona superblock model actually impacts urban life. This article suggests that this urban design could be a vital strategy for mitigating climate change impacts and improving public health.
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Welcome to today’s What is The Future For Cities podcast and its Research episode; my name is Fanni, and today we will introduce a research by summarising it. The episode really is just a short summary of the original investigation, and, in case it is interesting enough, I would encourage everyone to check out the whole documentation on the WTF4Cities website where you can find the shownotes and more information on supporting the podcast. This conversation was produced and generated with Gemini LM as two hosts dissecting the whole research.
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Speaker 1: When a patient comes into the emergency room with a severely clogged artery, the standard response is often to just insert a stent. You physically open up a specific channel to get the blood flowing again.
Speaker 2: It’s a highly localized fix.
Speaker 1: Exactly. It doesn’t instantly cure the patient’s underlying heart disease, but it brings immediate measurable relief to that specific part of the body.
Speaker 2: Yeah, but if their overall habits don’t change, the blood pressure just shifts. You haven’t cured the disease, you’ve just moved the strain to the next weakened artery down the line.
Speaker 1: And today we are taking that exact medical debate and applying it to urban planning. We’re looking at Barcelona’s famous superblocks. Basically, the city has been taking three-by-three grids of city blocks, restricting the traffic inside, and pushing all the heavy through traffic to the perimeter.
Speaker 2: Creating these internal pedestrian plazas with a, what? 10 kilometre per hour speed limit.
Speaker 1: Yeah, 10 kilometres for local vehicles only. And a major 2025 BMC public health study recently evaluated three of these early interventions: the Poblenou, Sant Antonio, and Horta superblocks. And the results are forcing us to ask: Are we curing the city or just moving the disease down the street?
Speaker 2: Exactly. Because while the intention is great, the execution matters. I’ll be arguing that these superblocks produce hyper-localized benefits but fail to solve systemic citywide issues. And worse, they actually create new safety hazards and socially exclude certain demographics by just displacing traffic.
Speaker 1: And I will be arguing that the superblock model is a proven evidence-based catalyst. It yields measurable improvements in air quality and community well-being. Treating a localized problem is a vital first step, right? Because getting cars out of city centres is a public health emergency.
Speaker 2: I don’t disagree there.
Speaker 1: And Barcelona has hard data proving this model works. Just look at the Sant Antoni superblock. They saw a 25% reduction in nitrogen dioxide, NO2.
Speaker 2: And a 17% drop in PM10 particles, I think.
Speaker 1: Exactly, PM10, those microscopic pieces of soot that cause respiratory disease. They plummeted. Plus, residents reported better sleep, more tranquillity, and increased social interaction. They are turning transit corridors into living spaces.
Speaker 2: I acknowledge those micro-victories, particularly in Sant Antoni, but the intervention is structurally flawed. Pointing solely to Sant Antoni ignores the failures we saw in the Horta superblock, an intervention that only works in highly controlled zones while pushing chaos onto the surrounding streets. That’s not a comprehensive solution.
Speaker 1: Wait, let me make sure I understand your reading of the Horta data. Are you saying the pollution didn’t drop inside the superblock, or just that it was pushed to the perimeter?
Speaker 2: It’s both. Researchers used passive diffusion samplers across the wider area, including the streets just outside the boundaries, and they found no overall significant air pollution changes in the wider area.
Speaker 1: But there were reductions in the interior, right?
Speaker 2: In tiny specific parts, yes. But think about the physics. The pollution just hit a brick wall and settled on the neighbours. Focus groups in Poblenou explicitly feared this. If you live on the perimeter, you are now absorbing the exhaust of the diverted cars. We’re actively engineering health inequalities based on who can afford rent inside the superblock.
Speaker 1: I hear that, but let’s go back to the medical analogy. Even with a systemic illness, you treat a severe localized infection. You don’t refuse antibiotics just because it won’t cure everything at once. Shouldn’t we celebrate creating clean air lungs within the city? Mobile atmospheric control units in Sant’Antoni showed an average decrease of 14.6 micrograms per cubic meter in NO2. That proves causality. Eliminate combustion engines, the air becomes safer.
Speaker 2: I don’t disagree that proving the concept has value, but you can’t ignore the immediate harm during this triage phase. The narrative of absolute safety in these blocks is frankly heavily compromised by how humans actually interact with them.
Speaker 1: Because the map’s walkability audits say the opposite. Horta scored incredibly well. Over 60% of people felt their walking comfort increased. Accessibility for strollers and wheelchairs improved massively.
Speaker 2: Yeah, that checklist measures how the street looks on paper. But look at the ethnographic guerrilla studies where they watched how people actually behave. In Sant’Antoni, families reported a false sense of safety.
Speaker 1: Wait, a false sense of safety? Meaning they felt too safe?
Speaker 2: Yes. The design tricks the brain. The painted asphalt, the removed curbs, it all suggests pedestrian priority. So parents drop their guard, kids run free, but cars are still passing through at 10 kilometres per hour, and drivers often still act like they have the right of way.
Speaker 1: That sounds stressful.
Speaker 2: Extremely. Pedestrians have to constantly snap back to reality when a delivery van rolls through their playground.
Speaker 1: But isn’t that just a behavioural adjustment period? That’s about re-educating drivers, not a flaw in the design itself.
Speaker 2: I’d argue it is a flaw if it ignores human behaviour. Let’s look at the disaster at the Horta main entrance. To remove barriers, they created one seamless level surface across the street, but they didn’t put up enough physical bollards, so cars just encroached. Pedestrians were dodging illegally parked cars in shared spaces. It was physically dangerous.
Speaker 1: I see the friction But isn’t the solution just better physical barriers? Add some concrete bollards. Enforce the rules. Don’t throw out the entire concept. The observational data shows families using these spaces extensively for rest.
Speaker 2: For rest, yes, but not for health. The city pitched superblocks to promote active mobility. But look at the Esso Park data.
Speaker 1: For the listener, Esso Park is basically researchers with clipboards counting how physically active people are in a space.
Speaker 2: Exactly. And in Sant Antoni, vigorous physical activity barely increased. It sat at a mere three point one percent. People sit on benches or walk slowly, but they aren’t getting the cardiovascular exercise the model promised.
Speaker 1: Demanding people treat a public square like a CrossFit gym is the wrong metric. Everyday mental health is just as important. Residents reported a vastly more relaxed environment. Adding greenery, removing the constant drone of car engines, it fosters community. The psychological relief of just existing outside without dodging traffic is a massive victory.
Speaker 2: A quieter street is pleasant. Mental health matters. But pleasant for whom? Because the qualitative data reveals some stark exclusionary findings.
Speaker 1: Exclusionary how? The spaces are entirely public.
Speaker 2: Physically public, sure, but socially engineered for a specific demographic. In Poblenou, teenagers explicitly felt the space wasn’t for them, so they abandoned it, and older adults actually found the Superbò isolated and harder to navigate.
Speaker 1: Because of the level surfaces?
Speaker 2: No, the transit routes. They had to reroute the public bus lines to the perimeter. For an able-bodied person, walking four extra blocks is minor. For an 80-year-old with groceries, it’s a massive barrier. They felt trapped. And on top of that, some women reported the deserted open areas felt unsafe at night.
Speaker 1: Because there were fewer people passing through?
Speaker 2: Jane Jacobs talked about the need for eyes on the street. Pull the slow flow of transit out, and on a random Tuesday night, those wide plazas become dead zones. If a design favours young families and office workers but alienates teenagers, traps the elderly, and makes women feel vulnerable at night, it fails the test of inclusive public health.
Speaker 1: Calling it an active failure is a bit uncharitable. I see those as the growing pains of a massive urban transition. The BMC study itself notes these are early iterations. We need more diverse street furniture, better microtransit options for the elderly, like local shuttles.
Speaker 2: But those shuttles don’t exist yet. The residents are living with the consequences now.
Speaker 1: True, but the core mechanism, reclaiming space from two-ton metal boxes to give it to humans, is undeniably sound. The issues are just matters of calibration. The 25% drop in toxic pollutants, the better sleep, the psychological relief, they prove that prioritizing human beings over vehicles improves overall health. It just requires tweaking.
Speaker 2: Calibration is doing a lot of heavy lifting there. My position is that the execution is dangerously uneven. Without a systemic citywide traffic reduction strategy, we just create fragmented, unequal pockets, clean sanctuaries for some ringed by displaced traffic for others. That cannot scale equitably.
Speaker 1: It is a massive challenge. But while we diverge on the implementation, I think we converge on the fundamental premise. Traditional car-centric urban design is inherently harmful.
Speaker 2: Absolutely. We agree completely there. The dominance of the private vehicle is a public health crisis. The question is just how we dismantle it without causing localized harm.
Speaker 1: Exactly. And to our listeners, reflect on your own city. If you’re stuck in gridlock, a car-free utopia sounds incredible. But what if your bus stop moves four blocks away to make room for it? How does your neighbourhood balance vehicles and human space? Ultimately, do we keep inserting localized stents, or are we ready for the systemic cure?
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