700 Fewer Deaths a Year. What Barcelona's Superblocks Mean for How We Plan Streets in New Zealand
With a cyclone over New Zealand over the weekend we had a bit of time to think about transport planning and network resilience. While watching an old episode of Faulty Towers (still a great comedy btw!) the classic line 'oh he's from Barcelona came up...' for some reason it made us think of the great work they have been doing with Superblocks in Spain...so much so we decided to explore in more detail! Enjoy:)
A peer-reviewed study published earlier this year found that if Barcelona fully implements its planned 503 superblocks, roughly 700 premature deaths could be prevented annually - through reductions in air pollution, traffic noise, urban heat, and increased physical activity. Life expectancy across the city could increase by nearly 200 days per resident.
Those are not projections from a theoretical model. They are based on measured outcomes from the superblocks already in place...including improved air quality, a 4-decibel reduction in noise in the Sant Antoni neighbourhood, and residents reporting meaningfully better sleep, wellbeing, and sense of safety.
For those of us working in transport planning in New Zealand and Australia, these results deserve serious attention. Not because we should copy Barcelona, but because they challenge some of the assumptions we've been operating under for decades....and because there was a soft link to Faulty Towers!
What a superblock actually is
The concept is deceptively simple. A superblock takes a group of city blocks (typically a 3x3 grid) and restricts through-traffic on the internal streets. Cars can still access properties within the block, but at walking pace (10 km/h in Barcelona). Through-traffic is redirected to the perimeter roads, which carry the network function. The reclaimed street space is then used for wider footpaths, seating, planting, play areas, and cycling.
It is not a pedestrian mall. It is not a road closure. It is a reallocation of existing street space based on a straightforward question:
who is this street actually for? Good question!
The genius of the model is that it doesn't require new infrastructure. It works with the existing road network. Planters, bollards, paint, and some signal changes can deliver a functioning superblock in weeks. Barcelona trialled its first versions as temporary, low-cost interventions before making them permanent - which meant communities could experience the change before committing to it.
The translation problem
Here is where it gets interesting for us. Barcelona is a dense, Mediterranean city with a famously regular grid layout, excellent metro and bus networks, and a culture where walking to a café is simply what you do. New Zealand and Australian cities are none of those things.
Our suburban neighbourhoods - the places where most New Zealanders and Australians actually live - are low-density, car-oriented, and built around cul-de-sac street patterns that already restrict through-traffic by default. You could argue that a typical Kiwi suburb is already a kind of superblock, just one where the reclaimed space went to private driveways and double garages rather than public life.
So the question is not "can we build superblocks in Hamilton or Christchurch?" It is "what would the superblock principle look like if we applied it honestly to the kinds of places we actually have?"
I think the answer sits in three areas.
1. Collector roads are the battleground
In Barcelona, the perimeter roads of a superblock carry the through-traffic. In a New Zealand context, the equivalent is the collector road...the street that connects your residential street to the arterial network. These are the roads where speed, safety, and liveability collide most visibly.
Most collector roads in our cities were designed primarily for vehicle throughput. They are typically 50 km/h (or higher in practice), have narrow or absent footpaths, and feel hostile to anyone not in a car. Yet they are also the roads that children cross to get to school, that elderly residents walk along to reach the shops, and that cyclists have no choice but to use.
Applying superblock thinking to collector roads does not mean closing them. It means asking whether 50 km/h is the right speed, whether the cross-section serves all users, and whether through-traffic could be managed differently to make these streets function better for the community they pass through. That is bread-and-butter transport planning — and it is exactly the kind of work that TIA assessments and speed management plans should be grappling with on every new subdivision and plan change.
2. The health argument changes the conversation
Transport planners have spent years justifying interventions in terms of level of service, intersection delay, and crash reduction. These are important metrics. But Barcelona's results show that the health impacts of street design (air quality, noise, physical activity, mental wellbeing) can dwarf the traffic engineering metrics we typically optimise for.
In New Zealand, where the health system is under sustained pressure and where non-communicable diseases linked to sedentary lifestyles are a growing concern, this reframing matters. A street redesign that adds 30 seconds to a vehicle journey but encourages 200 more people to walk daily is not a transport problem - it is a public health intervention. We should be measuring it as such, and presenting it that way to councils and communities.
For transport planners, this means building health outcomes into our assessments alongside the traditional traffic metrics. It means citing the Barcelona evidence (and the growing body of similar research from London, Paris, and Melbourne) when communities push back on speed reductions or reallocation of road space. The data is now robust enough to support that conversation.
3. The equity dimension cannot be ignored
One of the sharpest criticisms of the superblock model internationally is that it can accelerate gentrification. When you make a neighbourhood quieter, greener, and more walkable, property values tend to rise - and the people who most need those health benefits (lower-income households, renters, elderly residents) can be priced out.
This matters profoundly in the New Zealand and Australian context, where housing affordability is already a crisis. Any application of superblock principles needs to be paired with a clear-eyed view of who benefits and who bears the cost. Transport planners cannot solve the housing affordability problem, but we can ensure that our recommendations do not make it worse - and we should be explicit about those trade-offs in our reporting rather than leaving them as someone else's problem.
What this means for individuals
If you live on a quiet suburban street, the superblock concept might seem irrelevant. But think about the road you cross to get to your local shops. The street your children bike along to school. The collector road where traffic speeds past at 60 km/h because it is straight and wide and there is nothing to slow it down.
Barcelona's evidence tells us that redesigning those streets - not closing them, but redesigning them to prioritise people alongside vehicles - has measurable, significant effects on health, safety, and quality of life. Not in a vague, aspirational sense, but in a "hundreds of fewer deaths per year" sense.
The challenge for New Zealand and Australia is not whether the evidence supports these changes. It does. The challenge is whether we have the institutional willingness to act on it — and whether transport planners can make the case compellingly enough to shift the conversation from traffic delay to community outcomes.
Barcelona did not get here overnight. The first superblock was trialled in 1993. Thirty years later, the results speak for themselves. We do not need to wait that long - but we do need to start.
Til next time.
Andrew
P.s. Let's finish with a Faulty Towers quote today.
Transit Trends · Andrew Collings, KA Advisory. Read and comment on the original on LinkedIn.
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