(Unedited) Podcast Transcript 401: Health Gains for the Compact Walkable City
This week we’re joined by Billie Giles-Corti, Director of the Healthy Livable Cities Lab at RMIT, Melanie Lowe of the University of Melbourne, and Geoff Boeing of USC to talk about their papers in The Lancet Global Health series on Urban Design, Transport, and Health. They chat about the importance of walkability to public health, why Sao Paulo Brazil connects policy and outcomes so well, and how cities can use the detailed indicators they’ve created including bus stop and intersection density to fill policy gaps that lead to positive health outcomes.
You can find the papers at The Lancet Global Health
Below is a full unedited transcript of this episode:
Jeff Wood (1m 23s):
Melanie Lowe, Billy Giles-Corti, and Geoff Boeing. Welcome to the Talking Headways podcast.
Geoff Boeing (1m 49s):
Thanks for having us.
Melanie Lowe (1m 51s):
Jeff Wood (1m 51s):
Thanks for being here and welcome back, Geoff, who was with us on episode 275 before the pandemic,
Geoff Boeing (1m 56s):
How the world has changed? Huh? It’s
Jeff Wood (1m 58s):
It’s crazy. I think it was March of 2020 that you were on. It’s a little bit different these days, but we’re glad to have everybody here before we get started. Can you tell us all a little bit about yourselves and we’ll start with Melanie and Billie and then we’ll go with Geoff.
Melanie Lowe (2m 9s):
Yeah, sure. So I’m a research fellow in urban resilience and innovation at the Melbourne center for cities at the university of Melbourne in Australia. And my work focuses on policy analysis, looking at how do we get policy to support the creation of healthy and sustainable and resilient cities. And in this series, I led the first paper in the series where we did the international policy study.
Billie Giles-Corti (2m 33s):
So I’m Billie Giles-Corti. I’m the director of the healthy, Livable cities lab at RMIT university. And for the last 25 years, I’ve been looking at the way cities affect health. So how can we design cities to make people healthy? So that’s been the focus of my work And I, in this particular series, I led the first series where we came up with a set of indicators. What we thought were important that cities should be measuring and then initiated a new series that would see if we could actually do that globally. And so it was a really exciting challenge.
Geoff Boeing (3m 8s):
I’m Geoff Boeing. I’m an assistant professor at the university of Southern California’s department of urban planning and spatial analysis. I’m also the director of USCS, urban data lab, and a non-resident senior fellow at the Brookings institution. Most of my research revolves around urban planning and data science. So using computation to try to understand cities, particularly in the context of transportation and housing.
Jeff Wood (3m 34s):
So Melanie and Billie, I asked this to Jeff last time he was on the show, but I’m curious how you all got into cities and how you’re interested in the relationship between public health and cities. Was this something that happened when you were younger or is it something that evolved later on?
Billie Giles-Corti (3m 48s):
Well, perhaps I can go first because melon was my PhD student. So I started out a PhD. I went back in 90, 92, actually 30 years ago, I went back to university. I’d been traveling the world and knew a lot about cities because I’d been traveling a lot. And I started looking at really the world health organization had put out a new policy and it said it wanted to give guidance to member states about how they could promote health. And two of those guidelines were healthy public policy and creating supportive environments. Now healthy public policy is not creating good health policy.
Billie Giles-Corti (4m 28s):
It’s actually seeing how all policy could be health promoting. And it was a really good idea. It came out in 1986 and it was, you know, so very much hot off the press. I starting back at university at, in 1992. And so I took on the challenge of saying, well, what does that actually mean? There wasn’t much evidence around, it was a good idea, but there wasn’t much evidence around supportive environments or healthy public policy. And so I thought that would be a really interesting PhD topic. And that’s how I started out in this world. And, you know, when I look back now, of course it was a very naive the way I approached it, but it was a very comprehensive PhD.
Billie Giles-Corti (5m 8s):
I picked up, you know, planning, recreational planning, because I, you know, I didn’t really understand the behavior I was trying to measure. I was trying to measure physical activity and physical activity has lots of different domains. There’s recreational physical activity is going to the gym, there’s walking for Transport. And I started it that way. And in the end realized through the PhD that you had to narrow down And I started to narrow down and become much more interested in focusing on Transport and walking and Transport cycling, and also recreational walking and cycling. So becoming much more specific about the built environment that would encourage a certain behavior.
Billie Giles-Corti (5m 50s):
And so it was a really secured as route and in the end I’ve, you know, because I was interested in lots of different aspects of health, you know, we’ve looked at mental health, we’ve looked at dog walking and the way the built environment affects dog walking and how that affects health. And we’ve looked at safety. So because I had lots of different PhD students, I gave them all a different outcome measure, but we all used geospatial data, which is where we, Jeff comes in. We used all used the same geospatial data, but we all had different outcomes that we were interested in. And then along the way, of course, we realized that we need to change cities. And that’s where Melanie’s work came in. She started to do work on policy, which was her PhD.
Billie Giles-Corti (6m 30s):
So I let her tell you about how she got into it.
Melanie Lowe (6m 34s):
Yeah. So I was actually a physiotherapist first and working in a sort of clinical environment with patients. Who’d had a car accident and were undergoing rehabilitation. I was really interested in, you know, so I suppose the causes of ill health and was much more motivated to think about kind of prevention and, and populations as a whole, rather than working with individual patients who had already, you know, got sick. So I went back and, and studied public health. And in my public health studies, I became really fascinated by that close relationship between human health and our environments that we live in. And I, in this time, cities are the predominant human habitat, you know, they’re where the majority of people live.
Melanie Lowe (7m 18s):
And I was particularly, you know, curious about the kind of intersect of a lot of the 21st century challenges, you know, climate change issues around environmental sustainability, more generally urban environments contribution to that. And as well as its contribution to our health outcomes and, and fundamentally driven by a desire to tackle inequities between different population groups and, and different areas in our cities. I met the fabulous Billy Giles Corti at the end of those studies and, and started a PhD in the field of looking at how policy specifically can support the creation of healthy built environments. And, you know, the, the rest is history.
Melanie Lowe (7m 58s):
We’ve been working together with a team of others for a few years now on that program of work in Australia, initially as a focus and then increasingly internationally,
Jeff Wood (8m 6s):
Awesome. I wanted to have you all on because you know, there’s this really great set of pieces that you all put together for the Lancet global health, 2022 series on urban design. I’m curious first off, you know, for those who might not be familiar, what is the Lancet and why is it so important to the health discussion?
Billie Giles-Corti (8m 22s):
Well, the Lancet is a medical journal. It’s centuries old, it’s known well for it being a very high impact medical journal. But when you look back to what it was trying to do, it was trying to bring science to change the world for the better. And that was part of its original mission. And with the new editor, Richard Horton or not so new now, but the editor, Richard Horton, he wanted to go back to its original mission. And so when we published our first series in 2016, it was a departure. It was exciting to think that they would think about the built environment. They do a lot of things. Now they do climate change commissions. They look at obesity, they really tackle the upstream determinants of health.
Billie Giles-Corti (9m 3s):
Now, even though they still have obviously a very strong medical focus, we got on the cover of the Lancet. Our first series was in 2016. And honestly, just to give you a sense of it’s like, if, when you’re a researcher, it’s like being on the cover of the rolling stone, that’s how good it feels, you know, to be on the cover of the Lancet when you’ve got your own series, it was really big deal. And so, but for the Lancet to take it on is really important because it gives it the IPRO. When people in health look to know that something’s been published in the Lancet one, they know it’s high quality two, they think it’s important because the Lancet it’s picked it up. So I think for cities to be a focus for the Lancet in this case, it’s the Lancet of global health.
Billie Giles-Corti (9m 47s):
It’s got another, you know, different sorts of journals. Now it’s become so popular. The second series was published in the Lancet global health. You know, readers should know that the medical field, the health field see that this is a very important area and it’s high impact cause it gets cited a lot. So it’s a terrific to think that the city’s agenda is well and truly embedded. Now within the Lancet series of journals,
Melanie Lowe (10m 12s):
It’s really great that like the health community, I as represented by, you know, the medical journal, the Lancet, they really increasingly understand what I was talking about. That kind of close relationship between people and where they live, including urban environments and cities. And I think the increasing focus of that in the health sector is really indicative of a growing understanding that if we’re going to create a healthy population, when most people live in cities, we need to actually tackle those environments. And, and so the Lancet global health, we’re very supportive of this work that actually sets out how and what needs to change in our cities in order to address those kind of upstream causes of the causes of ill health, the majority of the world’s population in urban areas.
Jeff Wood (10m 59s):
So going back to like 20 15, 20 16, when the first one came out, how was that kind of initiated? And what did that first set of pieces tell you about, you know, what was coming next in 2022?
Billie Giles-Corti (11m 9s):
So the first series was really a gender setting. So I lead the first paper. It was led out of university of Melbourne. I was there as well. And Mark Stevenson, who was professor there he’d been a road safety researcher. And he had a relationship. He probably published in the Lancet before in his own research. And so he approached them about doing a series on urban design, Transport and Health. He was breaking into the field. I was well established in the field. So he asked me if I would write the first paper on city planning and Health and population health, a global challenge. And then he did one where he modeled what the impacts of city planning were.
Billie Giles-Corti (11m 49s):
So if we were gonna create more Compact cities, what would be the health impacts of that taking into account urban design, increasing density and street connectivity. And so he looked at a me particular cycling and he compared six cities globally and tried to estimate what that would be. And as Melanie said, what we’ve been focused on is that we can’t change cities unless the research that we’re doing gets translated into policy and practice. And so the final paper in the first series was saying, well, what does the evidence tell us about using evidence to inform practice and how important is that? And what do we need to do to ensure that we, one design research that will speak to policymakers and practitioners and to what needs to happen in terms of using that evidence and what will be the impact of that.
Billie Giles-Corti (12m 37s):
And so we had some case studies in it, so that was the first series. But in the very first paper I led, we said that cities should be benchmarking and monitoring themselves. And we came up with a, well, we were pushed by the Lancet. Actually, they wanted to say, well, what would be the metrics for doing that? So what would be the indicators? So that’s why we came up with a set of indicators based around in Transport. We talk about the five D’s for urban design, Transport, and Health to encourage Transport behavior or active Transport behavior. And so we came up with the eight D’s, three regional interventions and five urban design interventions that were needed to encourage people, to be able to walk and cycle and to use public Transport rather than drive.
Billie Giles-Corti (13m 23s):
And so what we wanted to do in the second series was to say, well, it’s all very well to say this, but is it possible to actually do that? We didn’t know that that was possible because we proposed policy indicators. So we would need to do policy analysis in cities, across the globe. And we would need to create spatial indicators to look at the distribution of interventions in cities. So how Walkable neighborhoods were, whether people had access to public open space, it’s easy to say create indicators that are comparable, but is it possible to do that? And we wouldn’t have been able to do this. You can tell by the research that we’re doing, this is a very multidisciplinary activity.
Billie Giles-Corti (14m 6s):
It requires a big team and it requires lots of different expertise. And that’s what we set out to do. We start, we went around to conferences globally, and we said, please join us. Would you like to join us and be part of this study? And so we were able to recruit by going to international conferences, more than 80 collaborators from 25 cities in 19 countries and six continents. So really exciting to do that, but really what was key to that was someone who could understand the policy work, which Melanie very much did. So that was, you know, it tied into work we’d done in Australia. So she was able to do that. We had been measuring in Australia, these spatial indicators.
Billie Giles-Corti (14m 48s):
And so my team contacted Jeff Boeing in California to say, would you be willing to play with us? Cause he was doing some similar work in other parts of the world. So we started to form this incredible collaboration. And so what’s amazing to me is that for, you know, over four years now, we’ve been meeting every month, our study executive thinking about how we can do this study and we’ve successfully published the Lancet series, but we’ve also got this group of collaborators who Melanie and, and Jeff can tell you about how we involved them, but we couldn’t have done the study without them. You know, it’s been a truly global endeavor and they were recruited through going to conferences and getting people excited about the possibility and telling them that one of our outcomes we were seeking was not only to do the study, but also to get a Lancet series out of this.
Billie Giles-Corti (15m 41s):
So that’s how the study came about.
Jeff Wood (15m 44s):
So once you get the indicators, the eight DS and you’ve added three more DS to get to 11, what do you do with them? Like what’s the process for pulling in the data for, you know, doing the research to connect health and urban form.
Geoff Boeing (15m 56s):
So I guess the first part of it is pulling in the data for this project. We did the combination. So a lot of our data came from public open data sources. So things like open street map to try to model transportation networks and pull publicly accessible amenity information, the global human settlements layer to understand boundaries and get some variables about urban areas about population economic productivity and so forth. But then the, the other part of it beyond just the public open data was that we worked hands on with our collaborators, both for validation of those data and also to fill in the gaps.
Geoff Boeing (16m 40s):
So they would take a look at our data sources and tell us what we were missing or what administrative data sets they had available at that city that they could turn over to us to put into our workflow. And it was that combination that really unlocked this research, you know, too often, for lack of a better data source, people will turn to something like open street map and just use it as the best available, but it has a lot of holes and gaps in it. And if you’re doing the sort of armchair research from Los Angeles and you’re studying cities in India and Vietnam and Belgium, it gets really hard to do that validation yourself.
Geoff Boeing (17m 21s):
So the, the collaborators were key to all of this, and that was one of the novel contributions of this project, combining those two together to do that better ground true thing. So we brought in that open data, we worked with our collaborators to validate it, fill in the gaps, and then we put it through our open source, computational workflow that we developed for the project. That’s all available online now for other folks to repurpose and calculate indicators in their own cities. Once we had those indicators Melanie on the policy side.
Melanie Lowe (17m 56s):
Yeah. So our policy indicators are really looking at the availability as well as the quality of policies across a broad range of sectors, you know, covering those Steves that you’ve mentioned. And so what we did is we developed a questionnaire that basically asked for information on local policy frameworks related to urban design and Transport systems, access to public Transport, public open space, things like air quality controls in land use and Transport planning. Also, whether there was sort of, you know, health goals and actions in policy, as well as government investment in active modes of Transport infrastructure. So we had this questionnaire and then basically our collaborators across the 25 cities, they provided the policy information for us.
Melanie Lowe (18m 41s):
So then we, we were able to know what policies were available in those cities. And also they gave us information about the content of those policies. And the great thing about that was, is that then centrally, we could do some analysis where we looked at what’s the quality of those policies, you know, it’s, it’s great that you have one, but is it a good one? And that assessment looked at, did the policy have, was it specific and did it have a measurable policy target to help guide implementation and hold governments accountable to that implementation? And also were the policies consistent with the best available evidence we have about planning for healthy cities or in fact, were they contrary to those goals of creating healthy and sustainable cities?
Melanie Lowe (19m 27s):
So we did that analysis centrally and therefore we could look across the cities and we could compare and contrast which cities had more complete policy frameworks, which ones had higher quality policy frameworks across the cities.
Billie Giles-Corti (19m 42s):
We know that from our work that we’ve done in Australia, we’ve been doing this now for a long time and we’ve really got to the stage where it’s, to me, it’s not a rehearsal, you know, the world’s changing and we need to contribute to that and we need to try and get our research translated into policy and practice. So based on that experience, what we did was we, and we’d done this in Australia for multiple cities as well. We created a scorecard for each of the cities, so we didn’t wanna just have the research published in the Lancet. Although that was very exciting. We got our cover of the Lancet again. So we, you know, big thrill about that. So that’s all very exciting, but that’s not enough to change the world and to change cities for the better. So what we did was we created scorecards for each of the cities, and this was a fantastic piece of work done by Cal Higgs in my team and, and Melanie working with Melanie.
Billie Giles-Corti (20m 32s):
And so he is created automated scorecards that we can take this complex data that we’ve collected and put it into user friendly format. But we did two things, a, a scorecard, which was like a little infographic, one pager that was done by Deb Salvos team then at the university of Washington. But what we also did was we created this report a little mini report. And our idea was that each of the cities could have a local launch of the results with policy makers and practitioners in those cities. And so we’ve been working with them to help them to set up a local launch and to get the research discussed locally with their local policy makers, to look at what can be done.
Billie Giles-Corti (21m 14s):
So there’s been a series of those throughout the world with our local collaborators, initiating these talks and working with their policy makers, either through advocacy or through doing a presentation and having a discussion to say, well, are we doing well? Are we not doing well? What can we do about it? Because we didn’t want it just to sit on, you know, our academic shelves and feel pleased with ourselves. We want it to be used. And the other things we’ve done is we’ve created a global Observatory where we’ve got all the scorecards are loaded up and they’re available free of charge. People can just go onto their look at the city of interest and they register because we wanna sort of collect to find out what sort of people are accessing the website, but they’re all available free of charge.
Billie Giles-Corti (21m 55s):
And we want to now expand that to the thousand city challenge. We want a thousand city to come on board and to use our tools and to replicate it because we’ve now got the tools that people can create comparable sets of indicators that we can compare lots of cities, but it wasn’t just a academic exercise. It had the end in mind, we’ve designed everything to be policy relevant, things that policy makers are interested in. So I think that this was another innovation of the work we’re trying to do is to try and change policy and practice.
Melanie Lowe (22m 26s):
That’s very true, Billy, very important. Also, I suppose, a, an innovation of the series is also having the spatial indicators that Jeff was talking about alongside the policy indicators, because that creates a really complete picture for decision makers. So they can go, you know, what are the strength and limitations of our policies and how can we improve the actual decisions that we are making about our cities and then also really target those inequities. So by, you know, looking at the spatial indicators and mapping those and seeing areas where there’s lower levels or, or disparities in access to things that are essential, like public open space, public Transport, walkability, then you can actually go, okay, where do we need to prioritize interventions in our, in our city?
Melanie Lowe (23m 9s):
So I think it’s having those two things side by side that really helps to create a, a complete picture to aid decision making. And then lastly, we had a paper in the series that explored what are the kind of minimum thresholds you need for some urban designer, Transport features in order to optimize walking and, and active living. And so that’s really fundamental so that if we say, well, you know, your policy is not ambitious enough. Well, we are starting to create the evidence about what would be the minimum requirements for provision of public Transport or street connectivity in terms of urban design, what you actually need as a minimum to support or optimize the, the health of your population with all of the co-benefits for physical activity, for reducing air pollution and greenhouse gas emissions.
Melanie Lowe (24m 1s):
So I think it’s that completeness of the work and hence the fact that we needed a team of 80, you know, to collaborate on that program.
Billie Giles-Corti (24m 9s):
So I think what’s important about this is there’s lots of indicator programs out there. You know, the economist intelligence unit doesn’t indicator, it does a citywide indicator. It tells you about an overall it’s a qualitative measure. Anyway, it’s not measured like we’ve measured, but I think what’s important is that most indicators are even the UN sustainable development goals are about the whole city. So what’s the average access to public open space or to Transport. Now that’s important in some ways, in terms of looking at inequities across countries and cities, but actually tells you nothing about the lived experience of people within those cities. And that’s really what the strength of having the geospatial indicators are, which I think were really important because as Melanie said, we can see now the spacial inequities in access to this amenity that’s health promoting amenity, that people need to live a healthy and sustainable life.
Billie Giles-Corti (25m 2s):
We are able to show that where the strength and weaknesses within the cities where the inequities are, and you can’t get that from just having a, an overall city-wide indicator. It doesn’t tell you anything about the lived experience of people within those cities and where the inequities are. So I think that was another strength compared to other indicator programs that we’ve seen globally.
Jeff Wood (25m 23s):
One of the things that you mentioned Melanie’s ambition, and you know, how much is this is determined by ambition for these cities. It seems like a lot of the cities have, at least I got this feeling from reading the papers was a lot of the cities that have policies. There are just because maybe it looks good to have a health policy on the books rather than actually something that might actually accomplish something. So I like this idea that you’re holding their feet to the fire with the indicators, because it seems like from the policy perspective, at least some of these cities are saying a lot, but not actually doing things.
Melanie Lowe (25m 51s):
Yeah. So that’s definitely what we found. You know, there was some cities that were better or worse at that, but really across the 25 cities, there was a, a lack of those specific and measurable policy targets. So lots of aspirations stated, or sort of, you know, policy rhetoric around creating healthy, sustainable, even equitable cities. But when you look at the detail there wasn’t that specificity to back it up. So you kind of left with a lack of those measurable targets to guide implementation and hold governments accountable. And then we also looked at, is the contents actually consistent with what no creates healthy built environments.
Melanie Lowe (26m 32s):
And whilst the vast majority of policies broadly do support those goals, even if they’re sort of just general aspirations, rather than those targets that we need. We, we found that actually some policy statements and policy targets were actually contrary to what we know and particularly around a lack of ambition, but particularly we found some cities didn’t have sufficiently ambitious targets for walking and cycling for public Transport use. So you set the benchmark too low and therefore, you know, where’s the drive for the sort of transformation we need of our urban environments to shift from car cities, to ones that, you know, have sustainable and active Transport systems. And I think also another area where there was a lack of ambition for some cities was in low housing density targets.
Melanie Lowe (27m 17s):
We need adequate housing density to support nearby destinations and therefore walkability. And so that was an area with low ambition for some cities. So these are the things that need to be, I would say, urgently revised, particularly if you’ve got a target, you know, a specific target that lacks that ambition, you’re really setting the benchmark to low and potentially locking cities into the unsustainable and unhealthy urban systems, which are not going to help us address the health and sustainability challenges of this century.
Jeff Wood (27m 48s):
I think I saw somewhere somebody wanted a 5% share for biking and walking, and that was like their ambition. And I kind of shrugged my shoulders at that.
Melanie Lowe (27m 55s):
Yeah. So in the us, we included Baltimore, Seattle and Phoenix. They were our three us cities. And I think it was Baltimore that you’re referring to that had a target by 2040 to have a 5% walking, cycling mode share to work and, you know, alone, it, it sounds like it’s pretty low, but particularly when we look at international comparisons, it really stands out. So place like Einstein, Denmark is an exemplar of cycling target. They had a target of something like 45% of trips to work being by bike and within a, within a shorter timeframe though, you see the huge gap in ambition between that city and Baltimore. And certainly we found that the Australian cities and the us cities had the sort of most car centric policy frameworks, and that’s perhaps not a surprise.
Melanie Lowe (28m 45s):
You know, Jeff can talk more to this, but we also found that those cities, similarly, when you look at the built environments that they had lowest levels of walkability,
Jeff Wood (28m 53s):
Well, that’s an interesting thing about walkability too, is like, why is walkability such an important factor in this whole discussion? And how does that connect to the outcomes in terms of health that you’re looking for? Because it seems like reading through the papers that walkability was one of the key ideas that ties the health part of it to the transportation, urban design part.
Billie Giles-Corti (29m 12s):
Well, there’s one thing you can do for your health is to be physically active. It’s really like the silver bullet. There’s nothing you can do. That’s more health promoting even in the face of other risk factors. Being physically active is really a fantastic thing that people can do just for their own health. And so we know that, and we know that walking is something that’s popular. So more people do more walking than any other physical activity. So we might think, you know, the going to the gym is important. People don’t need to go to the gym to get health benefit, to be physically active. They just need to walk more. And it’s, you know, it sounds pretty obvious if you live in a Walkable environment, you’re more likely to walk.
Billie Giles-Corti (29m 53s):
So if you can walk to the local shops and there’s some characteristics of a Walkable environment, so it’s the key thing to a Walkable environment that you’ve got local destinations. And so when you’ve got really low density, you don’t have enough people to make those shop services and public Transport viable. And so you have very few shops and services to walk to. And if you’ve got nowhere to walk to people, don’t walk. And the other thing that we include in our walkability index is the connectivity of the street network. Because if you live in an area where there’s lots of cul-de-sacs, you know, it’s a very secure route to get anywhere. People just tend to drive. Whereas if you’ve got a very connected street network where you’ve got lots of different routes that you can take, you know, so if there’s a dog down there that you don’t like, or there’s some houses that you might like to look at, you know, it’s an interesting street network.
Billie Giles-Corti (30m 40s):
Well, then you can go and take lots of different routes. So street connectivity, levels of density, not because density is important in itself, but because it makes the destinations more viable. And it’s really the destinations that are so critical because if you don’t have destinations, you won’t walks. And then the other thing is, of course, is what’s really important is to reduce the amount of traffic because we don’t measure traffic per sale. And I think we should, because what we know for cardiovascular disease that exposure to air pollution is really damaging to health. And in fact, now air pollution is the fourth leading cause of global mortality. You know, around 8 million people die every year because of exposure to air pollution from cars and cars are one of the biggest contributors to that.
Billie Giles-Corti (31m 23s):
So, you know, these built environment measures are really important for chronic disease or cardiovascular health. We used to worry in cities around communicable diseases, infectious disease, but now what we worry about is they’re impact of cities on non-communicable diseases or chronic diseases, the major ones that are preventable and causing so much your health and premature mortality.
Jeff Wood (31m 46s):
I feel like this is why the indicators are so important. And that discussion you were having earlier about comparing city to city is not as relevant to a person who’s walking in the neighborhood. And that’s why the neighborhood indicators seem to be very important at least to measure because of this, you know, this indicator of walking that tells you a lot about how people are able to get around and also gives an indication of their potential health outcomes as well.
Billie Giles-Corti (32m 6s):
Well, it’s harder to measure to get those. I mean, the built environment measures, even though I say this are easier to get, Jeff May not like may not agree that they’re easy to certainly, but they’re to get from every jurisdiction, the health, these are an indicator of the healthiness of the, the likelihood of people walking and using alternative to driving. So whether they’ve got the potential for an active and sustainable lifestyle is determined by these built environment measures and to create the built environment measures, you need a positive policy environment, which the indicators that Melanie has talked about. So what we’ve been trying to do here, we’ve, we’ve got a framework which says that if we want to promote health downstream, we need to be addressing the upstream determinants, the causes of the causes, and to do that.
Billie Giles-Corti (32m 56s):
That’s the policy environment, which determines what the interventions are, which the built environment, spatial measures that we’ve been measuring. So that’s why we measure the upstream because we think if you get these right, they are gonna produce a better health outcomes downstream, but most people don’t measure the upstream things. They, they tend to measure well, what’s the air quality like even in the UN sustainable development goals, their framework, they measure what the quality’s like, but to change the air quality, you need to change the policies upstream that will change the transportation behaviors that will produce better air quality downstream. So that’s what we’ve been trying to do is because we are focused on the determinants of health,
Geoff Boeing (33m 38s):
You know, and when you talk about the neighborhood scale indicators, it’s important to remember, that’s letting us do within city comparisons and analyses beyond just the normal between different cities within city is key because that’s how you start getting at questions of justice and equity within the jurisdiction of a, a single planning regime. You can say, which populations have access to health, promoting infrastructure and daily living needs within an easy walk and which don’t, and that’s something that’s a lot harder to tease out and reason with when you’re just ranking cities against one another, rather than unmasking, all that heterogeneity within individual cities.
Jeff Wood (34m 25s):
I think the IPEN study, I think it was paper two. This was what stood out to me. We estimated that population densities of at least 5,665 people per kilometer squared would be associated with the minimum 80% probability of walking for Transport and 6,491 people per kilometer square would be associated with a minimum of 58% probability of accumulating, at least 150 weekly minutes of total walking, which is the standard. So about 20 minutes, 21 minutes a day or so of walking is the standard for better health outcomes. And so this actually puts it together, why the densities are so important for walkability and what that means. I think overall for what you’re trying to accomplish,
Billie Giles-Corti (35m 2s):
It’s really critical actually, because it’s hard to do those sorts of studies. You really do need a very large sample. And so, because iPan the international physical environment network, they were a really big part of our study as well, because they’d already been doing this work in this area. But what’s interesting about these thresholds is that they global thresholds, but we actually estimate something similar in Australia. It’s not that dense actually for density, it’s around 25 dwells per hectare, which you may not use in the us. Jeff, can you convert that to acres?
Geoff Boeing (35m 33s):
Unfortunately, I cannot.
Jeff Wood (35m 36s):
14,000 people per square. Kilometer is 56 people per acre. And that’s the only one I translated cause I was trying to translate them as I was reading throughout the whole thing. But that’s the point where the negative relationship, if you get two dents, right? That’s the math that I did. So 56 units an acre is where the, the upper limit is. And I’m guessing that 25 per hectare is probably ha I don’t know, seven or eight or nine dwelling units per nine.
Billie Giles-Corti (35m 59s):
It’s not very dense. I mean, I, I guess that’s the thing, that’s the take home message here. We’re not talking high density. We’re talking modest density where you’ve got a mixture of different types of housing. So some people might live in an apartment, but other people would live in a house. Other people might live in a townhouse. It’s not very dense. And so I think that’s the take home. And we also found, as you just pointed out that there are upper thresholds that beyond which we start to see that walking will go down. So it’s not like we’re providing that. You know, every city should be really super dense, but we’re even in the suburbs. And that’s a key message here. We’re arguing that we need to be stopping the urban sprawl.
Billie Giles-Corti (36m 40s):
That is so characteristic of Australian and Australian and, and us cities and to put in medium density and modest amounts of density that would actually ensure that people have access to shops and services. And the interesting thing for us in Australia, we’ve done lots of studies. And we find that around two thirds of people would really prefer to live in a suburb where they could walk to shops and services. So I feel like there’s a latent demand for this product, which we’re not providing very much of
Geoff Boeing (37m 9s):
Jeff, you know, in, in the American context, when we start talking about density, people get scared, right? Yeah, exactly. All the political problems with planning start rearing their head. But as Billy was just saying, you know what we’re finding correlation here is that ideal levels of, of density for promoting physical activity. Aren’t scary density, you know, we’re, we’re not talking about central Hong Kong. We’re talking about the kinds of gentle medium density cities that Americans love to go on vacation too, right? Like Paris and so forth. That obviously there’s some kind of appeal to those kinds of places that I think we need to work harder as a profession to destigmatize in planning conversations at home.
Jeff Wood (37m 50s):
That’s interesting just every time I hear a, a dwelling units per acre, I just go back to Zan and PO curve from 1977, which they published a book called public transportation and land use. And the lower threshold for density that that was needed to support public transit was like nine dwelling units per acre in the us context. So those types of numbers are not very big. When you think about density and really 25 units per acre is the kind of standard that people talk about a lot here in the United States. But really if you think about commuter rail or other things, nine units and acres doable. And I think that once you get to a certain spot, you start to have those corner stores and have those access to destinations and other things like that. And I think that’s what makes the walkability so important here in, in my neighborhood in San Francisco, I can walk to the grocery store.
Jeff Wood (38m 32s):
I can walk down the street to get most things that I need, and actually I don’t have a car because of it. And so that makes it easy for me to do whatever I’m doing on a daily basis, but a lot of folks here in the us And I imagine in Australia, don’t have that opportunity because of the way that the built environment is. There’s also an interesting part about this, which is not just density, but it’s also, you know, transit stops in the area. And there’s also intersection density. How are all these other metrics tied in? I mean, we, obviously we talk about density a lot because it’s a hot topic, but there’s also other indicators that kind of mix in different parts of people’s transportation experience.
Billie Giles-Corti (39m 5s):
Well, connectivity is really important because what it means is if you live in an area where you’ve got really big blocks, you don’t have much choice. It doesn’t make a very connected street networks are really important because they provide people with alternative roots that they can take. And the more corner blocks you have, the shorter, the distance between where you live and where you wanna go, because you’ve, you know, you can almost do like a, almost a straight line. So that’s why lot length is really important. I went to Brazil for a trip And I was horrified at the size of the blocks of land, you know, so huge because if you wanted to walk around the block to just go around the corner to the other, you know, the next street, it was a huge walk.
Billie Giles-Corti (39m 47s):
And that’s why connectivity is so important because it actually reduces the distance that you have to travel to get to the destinations that you want to go to. So connectivity is really important of course, distance to transit’s important because the closer it is, the more convenient it is provided that it’s not gonna go on a secured as route. I mean, we don’t measure the route or the, the quality of the service, or we do do frequency of service, but we don’t look at the directness of the route, but that’s the reason why we put in distance to transit is because if it’s closer, it’s more convenient. And particularly if there’s a frequent service. So, I mean, these are all about making it really convenient. What we talk about in health, you wanna make the healthy choice, the easy choice.
Billie Giles-Corti (40m 27s):
And that’s what this built environment measures are about, is trying to make it easier for people to do it. And what we find is when we believe in easier environments, which are more Walkable, surprise, surprise, they walk, even if they don’t particularly light walk in, they walk more because usually in a Walkable environment, it’s, it’s less convenient for driving. And so what you find is that people I live in Fitzroy in Melbourne and, you know, it’s, I would never drive to the supermarkets cuz inconvenient to drive. I just have my little old lady’s granny trolley And I just go down and, and take my trolley and go shopping. And it’s convenient. So I’m really fortunate. And having that as you must be in San Francisco where you can get everything you need, don’t need to have a car and it reduces the cost of living as well because we’ve got cost of living crises all over the world.
Billie Giles-Corti (41m 16s):
And if you live in an area where you don’t need to drive, it really reduces the cost of living. It’s much more convenient and it’s cheaper.
Jeff Wood (41m 24s):
I just got a wagon to pull to the store. It’s it’s also for the baby, but it also helps me go to the grocery store now because I can put all the groceries in, in the wagon and bring them home without hurting my hands from the bags. You also mentioned Brazil, Billy. And it reminded me actually to ask you all about Sao Paulo, because it was given as a positive example of policy leading to outcomes. So I’m wondering what they’re doing so well to have that actually work out for them.
Melanie Lowe (41m 47s):
Yeah. So on the policy side we found, you know, we only had a smaller sample of middle income country cities, but in those cities, from middle income countries that we did include, we found that in general, they had more policy gaps and the greatest issues with the quality of their policy frameworks with a sort of standout exception. So Sao Paulo in Brazil really was a leading light. In fact, it’s policy framework in terms of policy presence, as well as policy quality outperformed, many of the cities in high income countries. And so this is terrific news that there’s these examples internationally of which Sao Paulo, maybe one that other low and middle income country cities can actually look to that it’s, you know, it’s not just the high income countries that have the capacity to develop those strong policy frameworks, but that, that can be regardless of levels of development.
Melanie Lowe (42m 43s):
So that’s a real, really important, I think message, you know, we certainly need to support policy making capacity in lower resource settings. And that’s a key role, I think for, you know, multi international organizations as well as the leadership of high income countries, but that there are examples of, you know, really positive policy framework out there.
Geoff Boeing (43m 4s):
Yeah. You know, finding those links between the spatial outcomes and the, the policy frameworks was, was one of the interesting things in this paper. You know, when we used Sao Paulo is one of the examples for doing a good job policy wise and then seeing it very clearly in the urban form when we measured with the spatial indicators. And we contrasted that with Bangkok, that Melanie’s team similarly founded had the greatest policy gaps and limitations and its implementation of policy. And we saw the exact same thing in, in the, the urban forum again, where it’s accessibility and walkability were very limited to certain corridors with huge gaps in, in the middle of the city.
Geoff Boeing (43m 44s):
So you, you really see the link between policy and the, the lived experience of, of people on the ground follows from it.
Jeff Wood (43m 52s):
How do you all hope that this framework will be used? You know, like what happens if cities start adopting these measures? Like they have NEC guides, for example, here in the United States to better design streets, like, is this a goal of yours to have, you know, every city basically use the same indicators so they can be compared against each other and then try to get those health outcomes you’re looking for.
Melanie Lowe (44m 11s):
I think that would be fantastic, but more so, not so much the comparison between cities, but using the indicators to, you know, firstly create stronger policies and fill those policy gaps, but also then commit to implementing those policies. So ensuring that, you know, there’s detailed implementation plans and that those that follow through to deliver the urban design and Transport features that people need to support healthy living in their cities. And then importantly, our ambition is also for those indicators to be used to track and monitor over time performance. So that it’s possible to see almost like an early warning system, whether there’s unintended negative consequences, you know, what’s working what needs to be changed in policy as well as its implementation to ensure that we actually move in that positive direction to achieve the sorts of goals set out in the sustainable development goals and, you know, international commitments around carbon emissions, we need to, you know, radically transform our cities.
Melanie Lowe (45m 8s):
And so I just think indicator a part of that effort to ensure that we, you know, know what is currently happening in our cities. And then we can actually track and monitor change over time. So we can work towards those design endpoints.
Jeff Wood (45m 24s):
You know, Jeff mentioned that Sao Paulo was kind of surprising and some of these connections were surprising. I’m wondering if there’s anything else that surprised you all about the work that you all did?
Billie Giles-Corti (45m 32s):
I think that was a surprise that Sao Paulo came up. I mean, it showed to me that there are some things that we didn’t measure. And we picked that up in our final paper where we said to where to next, I mean, the connectivity is really important. All the things that we found in Sao, but safety is a big issue there. So we didn’t pick up like how safe it is. And so there’s other things that we should measure in our cities that we should be picking up. And what we’ve done in the final paper is said that there are additional things. Originally, we were proposing the eight DS. Now we’ve gone to the 11 days because we’ve brought in that we not only have to protect human health. We also need to protect ecosystem health and planetary health.
Billie Giles-Corti (46m 13s):
And so our ambition has grown since our first series and doing this second series to say that we need to be putting additional indicators, you know, tree canopy for heat island effect. We need to be putting in measures of, you know, where people are building, you know, are we because of climate change, are people building in disaster prone areas, you know, flood and fire risk areas. And safety is one of those things. We didn’t have a measure of safety. It’s very hard to measure that because it requires, you know, data from police departments or who provide crime data, but we weren’t able to measure that. And I think that’s something that surprised me that someone like Sao Paulo came out so well because the built form was right and that’s fantastic, but we didn’t measure the crime there and people’s fear of being mugged.
Billie Giles-Corti (47m 2s):
And so that’s something that was, that surprised me. The other thing, like for Barcelona, for example, one of the big concerns, that’s got a great built form, but we didn’t pick up traffic. And so one of the big problems in a city like Barcelona, it’s got fantastic built form, but it also has a lot of traffic. So there’s additional indicators that we need to include that will tell you something about the quality of life and the quality in those cities. So there’s much more work to be done, but that was a couple of things that surprise me. Me.
Geoff Boeing (47m 30s):
I was just gonna add to what Billy was saying about the, the things that are hard to measure or perhaps even unmeasurable UN quantifiable aspect of, of cities. You know, one key thing that we flagged for future work was measuring the quality of the, the pedestrian environment. So, you know, beyond things like traffic and air quality, thinking about presence or absence of sidewalks, the quality of those sidewalks, how traversable and navigable is that pedestrian street system doesn’t matter if you have amenities a couple hundred meters away, if you know, taking your life into your own hands is trying to get down the street. And that’s something that it’s always hard to measure. There are no good data anywhere really for this open street map has some community around digitizing sidewalks, which I think would be a huge Bo if we have more folks contributing to the open commons, it would allow us to better understand measure advocate for intervene in those kind of environments.
Melanie Lowe (48m 28s):
What’s been a really pleasant surprise is like what Billy was saying, you know, with the launch of our global Observatory of healthy and sustainable cities, just the levels of, you know, engagement and interest. We’ve been immersed in this work for years. And obviously we’ve had the interest and engagement of a high profile journal like Lancet global health. But to see that uptake internationally, the launches in our cities that included in this study, the engagement of policy makers, people coming up to us who say, can I measure indicators for our city? You know, that sort of momentum is really delightful. And I think suggests that we’re on the right track here in terms of, there is a lack of information that people need and there’s that real appetite to get that information in the hands of decision makers so they can, you know, make those policies and, And I implement them for those health and sustainable city
Geoff Boeing (49m 18s):
Outcomes. You know, people wanna advocate for better cities. No, one’s more motivated than the citizens suffering under bad local governance. And the more we can empower citizen scientists to play a role in keeping their governments accountable for healthy living, the better,
Jeff Wood (49m 36s):
Where can folks find the papers if they wanna get them or contact you or, or get in touch for maybe being a part of the next next research project that you’re looking at,
Billie Giles-Corti (49m 45s):
They’re available free of charge for everyone to download. So they’re freely accessible. So on the Lancet that global health website on urban design, Transport and Health, but we’ll put the link and also people could have a look at the global Observatory. So it’s the global Observatory of healthy and sustainable cities. So again, the link can go on the website and there there’s a lovely infographic that the Lancet that global health did on the web, their website, which will explain all that we did in a very succinct way, very user friendly, and those who wanna dig down and read the papers in detail they’re available for people to use as well. One of the, the things we’d like to do is to invite other cities, to get involved, whole cities.
Billie Giles-Corti (50m 26s):
We want to measure throughout the world. So there’s a thousand city challenge and we’ll have details of that on our website. So the global Observatory of healthy and sustainable cities, you can find their details about how you can register to become one of the thousand cities to, to be in our big challenge. And we really love people to come on board with that. It does require putting together a team, someone who’s got some geospatial background, someone’s got policy background, someone who’s an advocate, there’s a job for everyone. So we really want people to put teams together and even work with their city to create these indicators. And that’s our big challenge now is to try and make this and even bigger Lancet series in the future where we have our thousand cities rather than just our 25 cities.
Billie Giles-Corti (51m 9s):
So that’s what we’re aiming for now. And that would be led by the next generation of gorgeous young things that are coming through our collaborators, who are really keen to take this to the next level. So it’s very exciting. A study like this is really important. It couldn’t be done without a huge team. And I, what we’d like to do is acknowledge the study executive who overseen the study, but also the collaboration, the healthy and sustainable city indicators, collaboration, an enormous group of people. Who’ve put a lot of time into this and really want to acknowledge and thank them for the work that they’ve done. It’s been a great team effort.
Jeff Wood (51m 41s):
Awesome. I’ll post everything in the show notes. We’ll have it in the link in the article when it comes out as well. But if you wanna go now healthy, sustainable cities.org is the place to go. Billy and Melanie and Geoff, thank you for joining us. We really appreciate your time. Thank
Billie Giles-Corti (51m 54s):
You. Thank you very much. Thanks so much, Jeff.