#90: Nature-Sensitive Urban Design, with Dr Thami Croeser

[00:00:00] Welcome to The Green Urbanist, a podcast for urbanists fighting climate change. I'm Ross.

[00:00:17] Hello, hello. Today's episode is a conversation with Thami Croeser.

[00:00:27] My name is Dr Thami Croeser. I'm a researcher at the Center for Urban Research at a university called RMIT University down in Melbourne, in Australia.

[00:00:37] And I'm an urban planner, so I love to think about how we use land. And I'd say probably for the last almost decade now my real obsession has been how we use land to get more nature back into cities.

[00:00:49] We talk all about his research on biodiversity-sensitive urban design and about how the urban design process can prioritize non-human living beings alongside people.

[00:01:00] We also talk about his research on the importance of connectivity between urban habitats and the way that, say, parks or ecological sites can be linked up through street greening, which is really important for boosting numbers of birds and insects and other creatures.

[00:01:16] Alongside the really practical advice for planning and for public realm design, we also talk about the often more boring and less interesting but really, really essential world of things like the politics and the governance of urban greening and why, although cities are often making big declarations on wanting to green their cities, what happens in reality often falls short of that.

[00:01:44] So we talk about unlocking some of those barriers that many cities face to doing that and why it's really important to focus on these things, even when we'd much rather be looking at the nice habitat spaces and that kind of thing.

[00:01:58] I had a really, really good chat. I really enjoyed it. It's full of practical advice and Tammy is just all around a really good guy as well. So yeah, I really hope you enjoy this conversation and I'll see you next time.

[00:02:10] I think something that's great about your research is it's very applied and very practical. Can you tell us, I suppose, in general terms, what's the focus of your research? Why are you pursuing that and sort of what sort of challenges are you tackling?

[00:02:27] Yeah, sure. So when I was starting out as a planner, I went and did my masters and we learned about all kinds of infrastructure, transport infrastructure, bridges, highways.

[00:02:42] You know, you learned about your hospitals, schools and how we place them and where we put them and those things are quite carefully planned. They're not always perfectly planned, but they're taken very, very seriously.

[00:02:52] And I just had a couple of lucky encounters with really good teachers who talked about green infrastructure and helped me understand that things like parks and trees and natural spaces are actually infrastructure as well.

[00:03:06] And I think that's partly because the research has been advancing so much over the last probably 30 years that shows our mental health and our physical health really depends on having enough of this green, green city.

[00:03:19] So what I think possibly a few decades ago might have seen is just been seen as decoration.

[00:03:26] Now we're starting to see us as real work, as real stuff that has to be done when you do a city.

[00:03:33] And I see my job as really helping us catch up on that because we've got terrible backlogs in most of our cities.

[00:03:42] I'm about to publish a paper that shows against a new benchmark for our mental and physical health that we're just desperately short.

[00:03:50] And that's in some of the greatest cities in the world. We really are way behind.

[00:03:54] So my big research focus is how do we get more nature into our cities and in the process, how do we make it beautiful?

[00:04:03] How do we make it nice and cool? So during heat waves, we get through all right.

[00:04:06] How do we do it in a way that soaks up floodwater because flooding is really a tough issue in urban areas.

[00:04:12] We've got concrete and asphalt over almost everything.

[00:04:15] And then there's all the questions around like, how do we make it encourage people to walk and exercise?

[00:04:22] So another one that I really love is how do we bring back native animals into cities?

[00:04:27] Australia has got such extraordinary native species and we don't see them very much in our day to day.

[00:04:32] In fact, I traveled to London earlier this year and I looked around and I thought this actually looks almost exactly like Melbourne

[00:04:39] because we've homogenized things so effectively in our cities.

[00:04:42] So I'd love to see a bit more, you know, native beasties around that's part of my work as well.

[00:04:48] Yeah, I think you've touched upon, I think all the reasons why I'm super interested in urban greening and urban ecology as well,

[00:04:56] which is that, you know, it's not just the biodiversity.

[00:05:01] It's also like or the visual aspect of it, which I think is maybe where maybe where a lot of people come from with it.

[00:05:07] But it's also about the health and well-being. It's also the climate adaptation and all of these things as well.

[00:05:13] And it's hard to think of anything else that can tackle so many issues at once.

[00:05:18] And actually, it for quite a low price tag compared to a lot of stuff we do in cities as well.

[00:05:24] There's so much to it. And yet we are still really, really bad at it.

[00:05:28] You know, it's this thing that we've been producing so much evidence on how great it is.

[00:05:33] It seems sometimes like such a no brainer, but the task ahead of us is quite substantial, really.

[00:05:39] Yeah. And I think we want to get onto that question of like barriers and how do we actually get this stuff moving a bit later.

[00:05:45] But let's get some of your other research first.

[00:05:50] It was interesting that you said about that London and Melbourne look so similar from an ecological point of view,

[00:05:55] because that is something that's happened with global cities as they have become very homogenised just with the movement of plants around the world,

[00:06:01] but also the way that exotic species have been moved around the world, sometimes on purpose, sometimes by accident.

[00:06:07] Yeah, that's fascinating. I've never been to Melbourne, but I would have just assumed it would have been very different.

[00:06:14] Oh no, you'd recognise our trees, our London plant trees, our poplars, our elms, all planted by the colonists back 200 years ago.

[00:06:22] Looks very familiar when we're over there.

[00:06:28] Let's get into it. I'm going to tee you up for some of your research.

[00:06:33] One of the things I came across was this notion of biodiversity sensitive urban design.

[00:06:39] Can you tell us what that is? Yeah, absolutely.

[00:06:43] So probably the last 20 years we've been talking about water sensitive urban design in Melbourne and in other cities around Australia.

[00:06:50] That's really the idea that when we do a street, we can put greenery in a way that we catch and absorb rainwater using nature and it cleans the water and slows down flood waters.

[00:07:02] And then in 2018, my colleague, Georgia Garrard came up with the idea, well, why don't we also do biodiversity sensitive urban design?

[00:07:12] And that's a similar idea that when we do a new suburb or when we do even just a new development site,

[00:07:20] even when we maybe just retrofit a street or change the streets, trees and stuff, how do we bring nature and particularly native species back into that in a meaningful way?

[00:07:32] And it's a lovely sort of well designed concept in that they've actually articulated very clearly in five pieces what the real principles are.

[00:07:43] And I'll just run you through those because I think it's just so neat in how it articulates this,

[00:07:47] because if you want to bring native species back as part of a development,

[00:07:51] whether you're doing a road or property or a whole precinct, a new housing estate or something, there's really five pieces, five considerations.

[00:07:59] And if you nail those, you're probably going to start seeing the animals that used to be there before that site was developed.

[00:08:05] And the first is really just creating habitat for those species and retaining whatever is there that's valuable.

[00:08:12] So in most urban environments that we live in, the issue is that maybe there is a little bit of greenery, but it's not very complex or layered.

[00:08:20] So things like understory planting, little shrubs, and they don't have to be dense necessarily for many species.

[00:08:26] But having vegetation or habitat patches that actually meet the needs of the native species that you're hoping to bring back is crucial.

[00:08:34] Another one that I've looked at a bit more lately is movement.

[00:08:38] So it might be great to have one or two little patches that support species that live in a city, but they need to be able to move around to find mates, to find food.

[00:08:47] Maybe if they have territorial disputes, they need to be able to move outside of their habitats.

[00:08:53] So having little stepping stones through the city so they can move around is really crucial too.

[00:08:57] And that might mean having smaller green spaces or little corridors through the city that creatures can move through.

[00:09:04] Then there's the third concept of really dealing with threats.

[00:09:07] So in some cases, well, in many cases, it's cats that get out at night and eat all kinds of birds and lizards and things.

[00:09:15] It might be making sure the weeds don't take over a natural patch.

[00:09:18] It's often a road that goes through a natural area and leads to lots of roadkill.

[00:09:23] You can manage those things, right?

[00:09:25] Last two points really quickly, bringing back natural processes.

[00:09:30] So if you're a lizard and I come past every two weeks and leaf blower clear the park and get rid of every leaf that has fallen off the tree, you're having a really tough time.

[00:09:41] If you're a bird and you need to live in a tree hollow, many of our native birds here live in hollows in dead trees.

[00:09:49] What do we do when a tree dies here in Australia and probably in London as well or England?

[00:09:55] We cut it down so we don't have trees with big hollows in many cases.

[00:10:00] So those kind of natural processes that many animals rely on aren't common in cities.

[00:10:05] Mowing is the classic big one that happens all over the place.

[00:10:08] It really takes things out that happen in nature.

[00:10:11] And then the last one, which is quite cute, I think, is get people involved with it all.

[00:10:16] So once you're bringing back lizards or birds or whatever it is that you want to see, help people recognise that.

[00:10:25] Hey, there's a native bee there or hey, there's bird species around.

[00:10:29] You can do all kinds of things.

[00:10:31] One of the things that we do here is we encourage birdwatchers or we even do things like bioblitzers,

[00:10:36] which are community-based counts of species where we encourage people to get out and see native animals in open environments.

[00:10:43] But there's loads of ways you can do it.

[00:10:45] There's loads of ways you can tailor all of these things.

[00:10:47] But those are the five principles of biodiversity sense of design.

[00:10:52] That's awesome. I really like that.

[00:10:54] I really like that. That's such a good framework to use.

[00:10:57] And as you said, it's five things.

[00:11:00] It's not 20 things.

[00:11:02] It's managed by the amount you can integrate into your work.

[00:11:06] This might seem like a tangent, but I will bring it back around.

[00:11:10] There's that classic urban design book, Responsive Environments.

[00:11:14] Did you read that when you were an undergrad?

[00:11:17] Responsive Environments? That wasn't on the reading list, Jan.

[00:11:19] Yeah, it wasn't.

[00:11:21] It's maybe more of a British urbanism canon type of book.

[00:11:25] It's from the 80s and a real classic.

[00:11:27] I actually have a copy of it here on my bookshelf that really sets out really fundamental stuff in urban design

[00:11:33] that a lot of urban design practitioners and researchers have built on since then.

[00:11:38] Really, really good book.

[00:11:40] One of the authors has teamed up with a couple of other researchers and practitioners

[00:11:48] to release a follow-on 40 years later, which is called Eco-Responsive Environments.

[00:11:53] It reflects this transition of early 20th century planning was really all about the car

[00:12:00] and mobility and moving people around in vehicles.

[00:12:04] Then as we got into late 20th century, early 21st century, it became all about the person.

[00:12:09] It was like this kind of thing, Responsive Environments, Jan Gale, all the stuff about put people first,

[00:12:15] then find space for cars later basically.

[00:12:17] It's more human life in cities.

[00:12:19] I feel like now the next frontier is this biodiversity sensitive urban design

[00:12:24] or urban design from a non-human perspective of what do all the other living things in the city need

[00:12:31] from spaces rather than just people.

[00:12:35] Indeed. Look, I really hope that we still nail that second stage where we figure out how to make cities human friendly a bit more.

[00:12:44] Most of the urban spaces I get through are car spaces everywhere.

[00:12:48] I think there's a strong interrelation between those things.

[00:12:52] I find it's so much easier to do all this bringing back of nature when 90% of the public space

[00:12:58] that you're working with isn't allocated to asphalts in the form of road lanes and parking.

[00:13:04] There's a beautiful overlap there.

[00:13:06] That paper that kicked off biodiversity sensitive urban design was published in 2018.

[00:13:11] This is brand new.

[00:13:13] I remember standing in workshops a few years back and we were starting to take people through some of this kind of thinking.

[00:13:19] It was fresh and it still really feels very, very fresh.

[00:13:23] It's an exciting space in a way, but it's also tough because it means that some of the things that are so well established in urban design for people,

[00:13:33] we don't know for birds or animals yet.

[00:13:37] So it's challenging in that regard.

[00:13:40] Yeah, there's a lot of specialist ecological knowledge that sort of needs to jump over into the built environment practitioners, I guess.

[00:13:50] Absolutely.

[00:13:51] How far can a thrush fly before it needs to stop and rest?

[00:13:55] I don't know.

[00:13:56] Do you know? Does anyone know?

[00:13:57] Well, there's probably an ecologist who knows.

[00:13:59] If I am asked that then I have to go and find out.

[00:14:02] And this is actually planning consideration.

[00:14:05] Yeah, totally.

[00:14:06] And I think there's an interesting question as well around how much do we attempt to design in this stuff and how much do we try and allow nature to sort of come about spontaneously.

[00:14:20] That, I find, is a really interesting conversation because I suppose we're, as designers,

[00:14:25] we always want to design the thing and have a sure sense of what the outcome will be and sort of dictate what the habitat will be.

[00:14:31] But of course, we can none of us can know everything and even a very good multidisciplinary team will have gaps.

[00:14:37] And sometimes I'm getting more and more interested in rewilding processes and this idea of can we just step back and sort of see what nature does and it might surprise us and often it does.

[00:14:50] Yeah, yeah.

[00:14:51] And I feel like that sense of agency and control is so intense, particularly in really built up urban spaces that it is very hard to persuade people to step back.

[00:15:01] I'm quite looking forward to traveling through Germany a little bit,

[00:15:04] hopefully next year and having a look at some of their streetscapes where they're starting to do that stuff a little bit more boldly than other parts of the world and seeing what is there.

[00:15:13] I still kind of imagine weeds, but I also think maybe that's just we're so early in this process of thinking differently about leaving spaces alone.

[00:15:23] Maybe I've got those prejudices.

[00:15:26] Yeah, and I think weeds can be great for pollinators and for aerating the soil and all that stuff.

[00:15:33] And they don't typically last very long. They're sort of an intermediate stage as you move towards scrubby habitat and things like that.

[00:15:40] I think an interesting thing is about the ecological processes often move at different timescales than humans are comfortable with.

[00:15:47] So we'll be like, this field is going to be covered in nettles for the next five years.

[00:15:51] But after that it's going to be a great habitat.

[00:15:54] It's really hard to sort of get your head around that or sort of make people comfortable with that.

[00:16:01] I think that's a really fascinating challenge of stepping back and sort of not mowing a space, for example, is making people feel that that is deliberate.

[00:16:12] And one of the things I've found quite wonderful as a concept related to this is this term cues of care, which essentially you might have an area that you've left to go wild for a bit,

[00:16:24] but you just mow a little strip in front of it and you keep that.

[00:16:27] It might be 30 centimetres wide, but it just means that person walking past goes, OK, that's not an abandoned lot.

[00:16:33] That's being left deliberately.

[00:16:35] And I think that's just so brilliant because if I walk past a field of completely wild nettles, I'm probably going to assume it's neglect rather than deliberate rewilding.

[00:16:46] Yeah, totally.

[00:16:48] And put up a sign.

[00:16:50] Yeah, that helps.

[00:16:51] Or an information board.

[00:16:53] Absolutely.

[00:16:54] It doesn't have to be a mystery.

[00:16:57] Within that paper on biodiversity sensitive design, you actually applied the principles to a regeneration site in Melbourne, didn't you?

[00:17:04] What were some of the findings from that exercise?

[00:17:09] Yeah, well, it was a very interesting process because we were looking at a really big urban renewal sites with a team that had been invited by the state government here.

[00:17:22] So that's kind of above the city level.

[00:17:24] And they have this big precinct that they essentially is a declining industrial precinct that they wanted to become a housing precinct with tens of thousands of homes.

[00:17:34] And they wanted a biodiversity strategy.

[00:17:37] So we designed a process to help think through that.

[00:17:41] And it was so fun.

[00:17:45] I didn't get to see it all the way through.

[00:17:48] But the first step was that we actually looked at what native species are around and what's in that area or what could be in that area.

[00:17:57] And then we sat down with a group of otherwise design and planning experts and engineers and said, what species should we try and bring back?

[00:18:06] And we invited some community groups to give us input as well.

[00:18:09] And we got extraordinary responses.

[00:18:11] We got native bees.

[00:18:12] We got an endangered frog that they said we should try and bring back.

[00:18:15] We got a beautiful stalk called a broga.

[00:18:18] One person even suggested that we try and bring back native fungi.

[00:18:23] And that got up.

[00:18:24] I think we have native fungi on that list.

[00:18:27] And defining what species you want to bring back to what's essentially a knocked out, rebuilt kind of project at a precinct scale was fascinating because you had to then go and look at what each of these creatures or fungi.

[00:18:45] Or I think we had some plants as well.

[00:18:48] What each of them needs.

[00:18:50] Okay, so we want to see native frogs coming back into this area.

[00:18:53] Where are they now?

[00:18:55] How will they get here?

[00:18:56] And then when they're here, what part of the new urban area is going to have little ponds for them?

[00:19:01] And how do we make those ponds not too close to roads and minimize the need to crossroads because frogs are not very good at that.

[00:19:08] Those are the kind of design principles that we started to extract by first getting the community's ideas and looking at what the tentative idea was for these redevelopment sites.

[00:19:19] And then trying to throw in all these ways that you can get the native bees back.

[00:19:24] You get the frogs back.

[00:19:25] We had a thing called a blue tongue lizard, which looks remarkably like a snake.

[00:19:29] It has very short little legs.

[00:19:31] And we had to think about how do we get this blue tongue to be in parks?

[00:19:36] But maybe not in a way that's going to alarm people.

[00:19:39] But also blue tongues are very vulnerable to dogs.

[00:19:42] How do we give it refuge from dogs?

[00:19:45] So in all those cases, we had really brilliant ecologists working with us who were able to tell us quite clearly what those principles were.

[00:19:52] And we produced this set of design principles, which then went into a biodiversity strategy for this urban redevelopment, which will be proceeding over the next 30 years.

[00:20:03] It hasn't even started yet.

[00:20:04] But I am hopeful that one day I will go there and see a blue tongue lizard and think it's a snake and get a fright.

[00:20:10] Amazing.

[00:20:13] So you think your report was commissioned by the city or are you just trying to influence them from the outside?

[00:20:20] So the one I'm telling you about was a commissioned consulting kind of job, particularly on the redevelopment of this new precinct in the Enfishments Bend.

[00:20:32] The more recent one that I did about ecological connectivity is just me blowing my own trumpet and then trying to advocate.

[00:20:40] But yeah, that one I'm quite excited by if it gets up.

[00:20:44] It's always a challenge in these really big precinct development processes when you're saying to people, OK, well, we need to kind of overhaul how we're doing streets.

[00:20:55] And you're already spending billions of dollars.

[00:20:58] Perhaps that was one of the learnings that we took from it.

[00:21:02] If we maybe had those conversations two years earlier before the streets were designed or even we contemplated how land was being used, I think we'd have had even more leverage to look at what goes into those spaces.

[00:21:16] Yeah, totally. And I think that ties in with another.

[00:21:19] You mentioned your paper about habitat connectivity within cities.

[00:21:22] Yes.

[00:21:23] Maybe that ties in well with it.

[00:21:25] Can you paint a picture for us what that paper was about?

[00:21:29] Totally, yeah.

[00:21:30] So I've advocated through various bits of research that we should be digging up asphalt in spots where it's not being used very much.

[00:21:41] So I'm not saying we need to rip up every road or anything like that.

[00:21:44] But really, we have been quite generous to cars in the development of our cities.

[00:21:48] And there are some areas which cars absolutely need.

[00:21:50] And then there's some areas that are a little bit poorly utilized where we've got really wide roads where they're not needed, where we've got dozens of parking spaces right next to parking garages.

[00:21:59] And I've developed mapping approaches that we can find out where those lower value areas of asphalt are that could be tended to green space.

[00:22:07] So I took one of those maps showing greening opportunities through inner Melbourne.

[00:22:13] And then I overlaid another map which I'd got from the city of Melbourne, which said these are the bits of our, I suppose, our network of green space that have that are kind of key missing links for habitat connectivity.

[00:22:33] So I had used a habitat connectivity model to identify these really difficult spots where there were disconnections between all these little fragments of habitat.

[00:22:45] And I said, well, what's the benefit that we might see if we do all of the greening that I see potential for versus what if we just target it on those spots?

[00:22:57] There's really key missing links.

[00:23:01] What kind of benefits do we see, particularly in terms of for your for the amount of greening that you have to do?

[00:23:07] How much benefit do we see for native species in terms of enabling them to move around by creating little bridges for them?

[00:23:15] So we again picked out some native species to work with.

[00:23:20] In this case, we've got this incredible insect which kind of lives just below the ground here called mole cricket.

[00:23:28] I don't know if they're common in the UK, but they have this incredible song.

[00:23:32] They're very it's a very beautiful evocative sound quite different to a normal cricket.

[00:23:37] And we pick them as one of our modeling species that are pretty rubbish at moving around.

[00:23:42] So they really need well-connected habitats.

[00:23:44] We've got this incredible bee, native bee called the blue banded bee.

[00:23:49] It literally has blue stripes.

[00:23:51] It looks like a little sapphire flying around.

[00:23:54] And then we've got a native bird that we tried out as well, the New Holland honey eater.

[00:24:00] And essentially the study looked at these three scenarios.

[00:24:04] We looked at what if we do all the greening?

[00:24:07] What if we do just a very small amount of greening on key habitat links?

[00:24:11] And then a third scenario looked at what if we try to do maybe double that greening and really focus on the habitat links?

[00:24:19] All the greening, minimal greening on key links and some more greening on key links.

[00:24:25] And essentially the big story was that if you do the minimal greening, you get almost even though you might connect up a few key links,

[00:24:36] a lot of the habitats remain fragmented, they remain isolated.

[00:24:40] So your creatures that aren't very good at moving around, particularly the mole cricket,

[00:24:44] but even the bee didn't manage to access lots of new habitat because what our model does is it looks at how that insect or that bird would move around the city.

[00:24:53] Right? If you do the bare minimum, even if you really target it very well, you don't get that much.

[00:24:59] However, if you target a reasonable portion of those key links,

[00:25:05] those sort of important bridges of habitat and you do a bit of greening in them,

[00:25:10] you get as much benefit as if you did almost everything for about a third of the amount of greening that you have to do.

[00:25:17] So we found that essentially you can get really good bang for buck when you're doing greening just by putting it in the right place.

[00:25:25] If you are able to, if you're planning a new urban forestry program and your greening program of some sort, making something totally unrelated to biodiversity,

[00:25:34] it might be that you're worried about flooding and you're doing rain gardens.

[00:25:37] It might be that you're an open space planner and you just have, you know,

[00:25:41] that 20% of each new park that you can make that has landscaping and that has some nice layering that could be habitat for bees or mole crickets.

[00:25:49] Right? You get choices in many cases where you put that.

[00:25:52] And if you can put that in a spot that links up habitat fragments,

[00:25:57] suddenly you might see insects moving through the city and more native species occurring in places than you'd have if you hadn't targeted.

[00:26:07] In fact, I think we saw that quadruple or triple the benefits.

[00:26:11] It was triple the benefits for the mole cricket in particular, just by targeting the investments in the right way.

[00:26:17] You see suddenly this creature which only occurred in two or three little spots could move

[00:26:24] and you'd have it in more and more parks across the city.

[00:26:28] And that means, you know, just with a placement decision of that park or rain garden or whatever you do, your child,

[00:26:36] you could be walking through the park and they might see a completely new bee, a new insect, or they might hear a new sound

[00:26:43] just because you connected stuff up in a clever way with a little bit of extra thought.

[00:26:48] So that was kind of just off our own bat.

[00:26:54] We thought maybe this is a new consideration we can insert into the practices of planets, of that kind of green infrastructure.

[00:27:02] That's great. I love that. That's great.

[00:27:05] And I think so often what I see in cities because of the way funding models work possibly

[00:27:13] and the way development happens in a patchwork around cities,

[00:27:16] where urban greening does happen, particularly street greening and sustainable drainage and that,

[00:27:22] it doesn't really happen in a coordinated way where they're thinking ahead of where connecting up spaces.

[00:27:28] It often happens where there's a pot of money available because there's a development happening here

[00:27:32] and we can tell them to put in the street greening here because there's work going on.

[00:27:36] So I think so much in conversations, it often comes back to this thing of needing stronger strategic planning

[00:27:44] to really look at these things ahead of time and coordinate it,

[00:27:47] which unfortunately seems to be missing, definitely missing in the UK, possibly in other places as well.

[00:27:53] Yeah, I mean, it's certainly a challenge to have these things planned and considered

[00:27:59] as we roll out green infrastructure, but an equal challenge is once you've got it on paper,

[00:28:07] realizing it in reality, I find.

[00:28:09] Yeah.

[00:28:10] You know, here in the city of Melbourne, we've got some very well-resourced councils that have got six or seven

[00:28:15] different plans for different aspects of their greening approaches.

[00:28:20] It's somewhat much simpler, but that ream of documents isn't always enough

[00:28:27] to actually realize the change on the ground.

[00:28:31] And when you were looking at your sort of connecting spaces up through the streets,

[00:28:36] what was the level of greening on the streets you were looking at?

[00:28:39] Was it street trees? Was there something more substantial than that?

[00:28:43] Yeah, so in terms of what we were actually putting in.

[00:28:47] Yeah.

[00:28:48] Yeah, so we actually spoke to a friend of mine who's an architect and a landscape architect,

[00:28:54] and he helped us develop up a small green space that was modular.

[00:28:59] And you could sort of vary it slightly to be a little smaller or a little bigger,

[00:29:03] depending on the size of the parking space that it was replacing.

[00:29:06] But it had three key elements. We designed it as a rain garden, so it was slightly below ground level.

[00:29:12] I think in the UK you call it sustainable drainage, right?

[00:29:17] We had understory planting, so we're very wary of creating sort of ambush hazards or safety risks.

[00:29:26] So we wouldn't ever do like shoulder-high shrubs or anything, but a few knee-high bushes,

[00:29:30] a few flowering plants, that kind of stuff. Maybe one shrub close to a tree but not too dense.

[00:29:35] And then with each parking space we always really tried to have a tree as well.

[00:29:40] And that just means that you don't just do biodiversity.

[00:29:43] You're also getting canopy cover and you're also getting rainwater interception,

[00:29:48] because once you're ripping up asphalt, you are spending substantial amounts of money.

[00:29:52] You really need to be trying to catch all those benefits.

[00:29:56] And with that little modular design, you can kind of cookie-cutter it out with a bit of confidence

[00:30:00] that it's often going to stack up in terms of the business case.

[00:30:06] Yeah, that's great. That's great.

[00:30:08] It's really interesting to hear you talk about understory so much,

[00:30:10] because I very rarely hear people talking about that.

[00:30:13] It's usually street trees or trees in general as like the main goal.

[00:30:21] But I think understory is often forgotten about.

[00:30:25] It's a true frontier. And I think in many cases it is challenging in urban environments

[00:30:30] because of that perception that it's an obstruction to sight lines.

[00:30:35] It might be that someone can hide in it and ambush you,

[00:30:38] but it's also I think in many cases this is terribly banal,

[00:30:42] but councils just don't have an asset class in their little registers

[00:30:46] of all the things they own for shrub.

[00:30:49] They just don't know how to code it.

[00:30:52] And that means that they don't have a person whose job it is to maintain it.

[00:30:56] And yeah, it just doesn't get done.

[00:31:00] But if you think about it from the perspective of being a little bird or a lizard or something,

[00:31:07] that just a street tree in the ground often planted directly into asphalt,

[00:31:12] almost asphalted right up to the roots or with a little one by one meter square,

[00:31:17] that's actually really crap habitat.

[00:31:19] You need a little bit more than just that tiny sparse space.

[00:31:24] And it's an uphill battle to persuade people that this is the new thing that we have to do.

[00:31:30] But from a bird's perspective, it's essential.

[00:31:37] Yeah. And I think as an anecdote in terms of the connectivity aspect of why that's important.

[00:31:43] So there's a really small nature reserve in East London where I'm involved in.

[00:31:48] I volunteer there sometimes. Amazing space.

[00:31:50] It's just a little pocket of woodland that has like a pond in it,

[00:31:53] in this very urban neighborhood.

[00:31:56] And up until, well, for a couple of decades,

[00:31:59] it was well known for having a really thriving population of frogs in the pond.

[00:32:04] And people could hear the frogs croaking from their apartments around and stuff like that.

[00:32:09] And then at some point they just disappeared.

[00:32:12] And there was no particular event that sort of signified why that happened.

[00:32:16] But the site managers told me that they reckon the population was just so isolated

[00:32:23] that it just lost genetic potential to keep reproducing basically.

[00:32:27] And they just hit a dead end basically and died out.

[00:32:32] So they had nowhere to go.

[00:32:34] They just needed more.

[00:32:36] They needed to find other frogs in the neighborhood to mate with basically.

[00:32:41] So that's like a really good, unfortunately quite sad illustration

[00:32:45] of why there needs to be ways of connecting these together.

[00:32:49] But frogs are amazing.

[00:32:51] I have a friend who was renovating a house down south in a city outside London.

[00:32:59] And he put in a little pond in his garden.

[00:33:02] And literally the next day there was a frog in it.

[00:33:04] He was like, where did you come from?

[00:33:06] How did you know?

[00:33:08] Yeah, but I mean, I guess even if I'd been planning 15 years ago at uni

[00:33:15] and I'd come across a subject on streetscape design or transport networks or something,

[00:33:23] I would have been baffled to get a frog module.

[00:33:27] So no one's thinking about it.

[00:33:29] And it is obscure.

[00:33:31] But really I think that's so beautiful to think

[00:33:36] that those people in that very dense bit of East London could hear a frog song.

[00:33:40] I know what that sound feels like to fall asleep to.

[00:33:43] And these are the things we lose when we don't plan these things out.

[00:33:47] And I think it's very difficult in a very quantitative cost benefit environment

[00:33:53] to make a case for those experiences.

[00:33:56] But that's a terrible thing to lose for those people.

[00:34:00] And connectivity planning probably would have saved it.

[00:34:03] Yeah, for sure.

[00:34:05] Fascinating.

[00:34:07] I think there's also something I think I've mentioned on the podcast before.

[00:34:13] I've definitely wrote a newsletter about it a couple of months ago.

[00:34:17] This thing of like, I think there's some big opportunities,

[00:34:22] sort of opportunity within crisis moments for urban planning

[00:34:27] in a lot of cities coming in the next couple of decades.

[00:34:29] And I think a big part of that will be aging infrastructure.

[00:34:34] So all this big reinforced concrete infrastructure

[00:34:38] that's coming to the end of its lifespan in sort of the 2050s, 2060s.

[00:34:42] We're going to have to figure out what to do with it

[00:34:44] because it's going to be sort of unsafe and either needs to be rebuilt,

[00:34:47] which hopefully will not happen in most cases, or will be reimagined.

[00:34:52] So imagine all of the heavy road infrastructure, flyovers, massive roads.

[00:34:59] That now we can, we have an opportunity, they have to come down.

[00:35:02] So we have an opportunity to rethink those as like habitat connectivity,

[00:35:06] cycling routes, much smaller streets that can serve the human and the non-human life.

[00:35:13] So I think that, you know, and by nature, a lot of these big infrastructure

[00:35:17] tends to sort of cut through cities in quite a substantial way

[00:35:21] and have been barriers.

[00:35:23] So maybe that's an opportunity to start thinking about like these ecological corridors

[00:35:26] that can start to knit together cities again.

[00:35:30] I mean, Rob, sir, I don't think we have to wait decades and decades.

[00:35:33] Every asphalt road is on a renewal cycle.

[00:35:37] You know, I think here it's often 10 or 15 years.

[00:35:40] And as the climate gets hotter and hotter and we have more heat waves,

[00:35:43] the roads are lasting less and less.

[00:35:45] And just the straight down the road from me got resurfaced the other day

[00:35:49] and they peeled up all this asphalt.

[00:35:51] And I felt this incredible pregnant moment of opportunity where it could be anything.

[00:35:55] And then the truck came and rolled, you know, a whole sheet of fresh black asphalt.

[00:36:01] I think it's the last one and as completely abiotic

[00:36:05] and they didn't do anything to decompact the soil.

[00:36:08] They didn't do anything to improve infiltration.

[00:36:10] There certainly weren't any new tree planting spots.

[00:36:12] But every street by the time, you know, we're 50 or 60

[00:36:17] will have been probably redone once or twice.

[00:36:20] And every time that is redone, that's a missed opportunity to change our standards.

[00:36:26] I think, you know, this idea that renewal can be a renewal to a higher standard is so exciting.

[00:36:34] And I've never thought about it for big infrastructure like flyovers.

[00:36:37] But every little road, if we change design standards in little local governments

[00:36:43] that say, hey, when we pull up that's what we're actually going to put back permeable paving instead.

[00:36:48] Now we're going to decompact the soil and we're going to create root volumes.

[00:36:51] So we're going to put in a tree between every three parking spaces.

[00:36:54] Don't have to be radical.

[00:36:57] Those are actually quite simple things to do when you're already ripping up the road anyway.

[00:37:01] And what you put in might actually last longer because it's not asphalt.

[00:37:06] And those changes in standards are potential right now.

[00:37:12] And they could incrementally give us very different cities over the course of the next three or four decades.

[00:37:17] Yeah, totally. Really well said.

[00:37:19] Well, I think that maybe that takes us on to the next question, which was all about.

[00:37:23] OK, so a lot of cities around the world are I think are quite switched on to the benefits of urban greening

[00:37:31] and are certainly making a lot of positive noise and targets around that,

[00:37:35] around things like tree planting or street greening, etc.

[00:37:39] And yet we often change is very slow basically.

[00:37:43] And often those those those ambitions aren't followed through on or done very slowly.

[00:37:49] Do you have a sense of what the sort of major barriers are to delivering this stuff and what we might do, how we might unlock them?

[00:37:57] Yeah, absolutely. I mean, I think it's.

[00:38:00] It's it's very easy to talk about benefits and a lot of us are very good at talking about benefits.

[00:38:07] And I think even now an enormous amount of scholarship is still going on to demonstrate that things that we know are good are good.

[00:38:14] And in some cases, we do need more numbers on those things.

[00:38:17] In some cases, I'm not sure we do.

[00:38:20] Similarly, conceptual frameworks on what's important and agenda setting and that kind of stuff.

[00:38:26] We kind of know what needs to happen.

[00:38:28] We need a lot more greenery in our cities. We need more trees.

[00:38:31] We need more parks.

[00:38:34] But there is there is a huge amount of thinking and research still going on, reframing things, you know, like this term nature based solutions came along about five years ago in my career.

[00:38:44] I went, hang on, we're rehashing great infrastructure, which was just the thing before it.

[00:38:49] So there's a lot of tail chasing, I think, happening in our fields.

[00:38:52] And it does distract people quite a lot because they might set aside a strategy that's perfectly good and hasn't been implemented and rewrite it as a nature based solution strategy.

[00:39:00] And maybe it'll be marginally better.

[00:39:03] And that's that's OK. But I think the core work of not just setting targets and talking about how great it will be to set the targets, which is the stuff that's free to do.

[00:39:13] But then following through with the implementation is the crucial bit.

[00:39:18] And I think that's still, as you say, what's missing?

[00:39:22] Why is it not happening? Well, there's there's a couple of things that I've noticed.

[00:39:26] Firstly, people who do greening in government roles are not very powerful.

[00:39:31] They tend to be in a marginal sustainability team.

[00:39:36] Their job is to deliver a bit of greening and even in cities or urban areas that I've worked with that have quite big, powerful, say, for example, urban forest teams, open space teams.

[00:39:48] Their budgets aren't very big and they do not have significant control over how land use decisions are made.

[00:39:56] They take those land use decisions around what the street looks like, what how much park space we can reclaim, where things go.

[00:40:06] Those those decisions are ultimately taken to engineers and those engineers in many cases are actually quite nice support of people.

[00:40:13] But their job is not to maximize greening, not in formal terms.

[00:40:17] Their job is to minimize risks and the easiest way to minimize risks is to say no to things.

[00:40:21] And so you end up with people who do not have massive authority and do not have massive budgets trying to implement a plan which is massively ambitious.

[00:40:32] So city of Melbourne right here, we've got a plan to reach 40% canopy cover target over public space by 2040.

[00:40:40] So we've got another 16 years to deliver 180 hectares of new tree canopy cover, which is just like many, many, many football fields in a really built up urban area.

[00:40:50] And that ambition was great.

[00:40:52] And we're all celebrated for that ambition here.

[00:40:54] And it's still like a bit legendary, but we're making quite slow progress towards it because we don't have the authority to rip up asphalt in those teams.

[00:41:04] They are getting a little bit better persuading, but it is persuasion, not power.

[00:41:09] So in terms of making things move faster, I think some of the most important stuff we can do is reform roles and responsibilities so people whose job it is to live a greening are actually big players who can make land use decisions.

[00:41:21] Those governance structures also often have legislation or policy that determines how things happen and how decisions are made.

[00:41:31] And if you are going to engineers to make a call, those engineers could actually really help if they feel that it's their job to make sure that there's more trees in the city.

[00:41:41] When they do that, when they do feel that they can be fantastic allies.

[00:41:45] But until those big governance decisions are made saying no, the urban forestry team actually has a lot of power.

[00:41:51] When we come to the engineers, they're part of the urban forestry team or their job is to deliver canopy as well.

[00:41:58] There's all kinds of legislation which holds things back as well.

[00:42:01] For example, power cables here lead to massacring of quite beautiful mature trees all over our city.

[00:42:07] That that's enshrined in legislation that there must be ex clearance.

[00:42:12] I think it's one and a half meters from any large branch and a power pole.

[00:42:15] That legislative work is boring.

[00:42:18] There's a lot of conflict in it, and it's really unsexy stuff, often with many stakeholders who are very niche and narrow and have their blinkers on and don't want to talk to you.

[00:42:29] That's the boring hard work that is not getting done.

[00:42:32] That governance reform stuff is really crucial.

[00:42:35] And then, of course, the other aspect of it that is boring and hard and stressful is finding the money.

[00:42:42] Ultimately, if we want to rip up lots of asphalt and get trees in and deliver hundreds of hectares of new green space,

[00:42:52] we're probably going to need to spend hundreds of millions of pounds or possibly billions.

[00:42:57] New York has spent a billion dollars over the last decade on their green infrastructure program, and that's just flood mitigation.

[00:43:04] So retrofitting a big city is expensive.

[00:43:07] And then that links to the third and final piece for me that I think none of us in the built environment professions are very specialized in, which is politics.

[00:43:17] I'm not very good at running a political campaign.

[00:43:20] I'm not very good at running a persuasion campaign to let me reform a street and persuade people to actually take out a third of their parking.

[00:43:29] I'm getting better at that kind of stuff.

[00:43:31] I have done it in some projects in earlier parts of my career, but it's not something that comes naturally when you've maybe been trained in ecology or

[00:43:41] or urban planning or landscape architecture.

[00:43:44] The politics of that stuff, that local politics, is pretty tricky.

[00:43:48] And it's not just the people on the streets that you've got to be able to persuade.

[00:43:51] It's also the politicians who hold the purse strings and authorize things like a road closure or significant design changes to a street.

[00:43:59] They're very sensitive to objectors.

[00:44:01] And you need to really be quite effective at persuading politicians to put down money.

[00:44:07] And then when it's time to change land use, follow through and have the guts to follow it through, that politics aspect is really tough.

[00:44:15] And it's not sort of a main suit in our field.

[00:44:19] So yeah, to summarize, governance, money and politics, those are the boring things that we've got to learn to do better if we actually want to see change

[00:44:28] at scale in our cities.

[00:44:31] That makes sense to me.

[00:44:33] And I think that sort of chimes with experiences I've had.

[00:44:39] It's interesting that I think in some cases, a more sort of courageous approach to doing these things sometimes has benefits and sometimes backfires because

[00:44:51] I mean, there's a great example of a city in Spain, which I always forget the name of, where in the 1990s, the early 2000s,

[00:45:01] the city pushed forward with making the whole historic city center car free.

[00:45:06] And at the time, the majority of people in opinion polls were opposed to it.

[00:45:11] And then 10 years later, the majority of people supported and would never go back to the way it was before.

[00:45:16] So that's like a nice example of a sense when you can have a strong vision and you know something is in the public good.

[00:45:24] Sometimes you can't wait around to convince everyone to do it, but you sort of have that courage to try it and see if people are convinced then.

[00:45:33] But then the opposite of that is like in London across the UK during the pandemic, we pushed forward with lots of street redesign and street closures to promote active travel.

[00:45:44] And there was literally in some cases riots and destruction of property as people were so angry about it.

[00:45:53] And totally backfired and now makes it really difficult to do those projects.

[00:45:58] And they have to happen in a much slower way with a lot more like working closely with people, which is the better way to do it anyway.

[00:46:05] But yeah, it's interesting.

[00:46:07] Yes, no, I mean, it is fascinating watching the active transport people because I think they might be a few steps ahead of us in the greening space where you do have places like Paris, which are now moving very, very boldly in the rollout of things.

[00:46:21] And I am very much in favour of trialling things carefully and establishing ideas a bit more.

[00:46:27] I do sometimes think maybe we've moved a little too fast, but I'm watching places like Paris and just being quite amazed in that it is moving forward.

[00:46:37] And honestly, from here in Melbourne, what you guys have done with low traffic neighbourhoods is impressive.

[00:46:42] I understand that it's caused chaos and I've heard some extraordinary conspiratorial stuff about Oxfordshire with the 15 minute cities becoming checkpoints.

[00:46:51] And it crops up in community meetings here.

[00:46:54] There is an incredible pushback, but it's a dynamic space and I think all of us are weathering the politics of it a little bit.

[00:47:03] But yeah, I do love the idea that we can push forward, we can try things out and maybe in non-permanent ways and then show people that they'll be alright and then eventually establish things more permanently.

[00:47:19] You mentioned Paris and New York there as potential good examples.

[00:47:24] Can you think of any cities that you would hold up and say, actually these guys are doing really well and we can learn from them?

[00:47:30] Oh yeah, there's a lovely story of Montreal opening, you might say, a bunch of its streets.

[00:47:40] They've done a very large systemic change of its streets to enable greening.

[00:47:46] The one that I've been really excited about lately is you've probably heard of Barcelona's Superblocks programme where they closed up these kind of internal sections in a grid of nine.

[00:47:57] And they let traffic around the outside and then the internal bits were kept.

[00:48:01] And I went and looked at a couple of those before the pandemic and I wasn't incredibly impressed.

[00:48:06] They seemed kind of alright, they kept most of the asphalt, they put the trees in tubs, the trees didn't look particularly healthy.

[00:48:13] The streets were still kind of asphalt streets, but with cool paint on them.

[00:48:17] It was an improvement, but I didn't see what all the fuss was about.

[00:48:21] But what I didn't understand was this was them giving it a go and testing the waters a little bit.

[00:48:27] And I think there was still controversy around it, but it's established now.

[00:48:31] And now they're moving forward with more permanent, more thorough iterations.

[00:48:36] I saw the renders of some of those the other day and they're actually ripping up the asphalt and putting in these things that look like forests.

[00:48:44] And you'll kind of be able to walk down the street in a kind of real foresty environment.

[00:48:50] And hey, it's free to do renders.

[00:48:54] Maybe they won't be able to pull it off to that degree, but it looks extraordinary.

[00:48:58] And yeah, so I'd be watching Barcelona very closely indeed.

[00:49:03] And from my perspective as particularly an advocate of using parking spaces, the one that I find exciting is Paris because they've talked about reclaiming.

[00:49:12] I think it's 70,000 parking spaces in the next decade.

[00:49:17] That's an extraordinary area of land that could be reused.

[00:49:22] And I think some of that will go to bike lanes, but I think the intention is that a fair bit of that will go to greening.

[00:49:26] So yeah, keep your eyes on those two.

[00:49:29] I know they're kind of old classics, but both worth a closer look if you're keen to follow up after this podcast.

[00:49:36] Yeah, totally, totally. That sounds great.

[00:49:41] An interesting one as well is Milan who have done a lot some really interesting like trialling work, low cost sort of tactical urbanism stuff where they've taken bits of like overly sized junctions.

[00:49:55] And residential streets and stuff and literally just use paint to sort of demarcate new spaces for pedestrians.

[00:50:03] They've put in school streets and they've made new public spaces out of what was just this overly sized highway infrastructure.

[00:50:10] And it's not, you know, a lot of it has sort of aged now a couple of years and the paint is fading.

[00:50:14] And you know, you might look at it and think like, OK, it's not like world class public ground design, but it's not really meant to.

[00:50:22] I heard a podcast with one of the guys who is running it in the city council and he said, he said this literally started with like three members of staff, two of which were interns just like deciding to give it a go.

[00:50:34] And doing it with like no money.

[00:50:36] And it's been hugely successful.

[00:50:38] And now they're getting the momentum to do more permanent stuff with more greening and stuff.

[00:50:42] So yeah, definitely power in local experiments for sure.

[00:50:47] You know, just to just to wrap that one up.

[00:50:49] I mean, the lovely thing about those quick, simple tactical things, you know, it does create space for greening.

[00:50:55] It does create space for all these things.

[00:50:57] But it's also something that's so cheap and easy for locals to participate in.

[00:51:02] You know, when you when you do some public realm projects, you have these high profile, big eco-architects, landscape architects, urban designers who want to control everything.

[00:51:12] And to some degree, they can argue quite fairly on the expert.

[00:51:15] I know how things will be best.

[00:51:17] And that's maybe appropriate at that later stage when you've got the social license to make those big changes.

[00:51:23] But in the short term, give people buckets of paint.

[00:51:26] Let them let them experiment.

[00:51:27] Bring them into that stuff, because if people feel some agency in changing their public spaces, I think they're much less likely to become angry or conspiratorial or just once the trials over, say, oh, we didn't like that because they feel ownership and belonging as participants.

[00:51:44] So big fan of what's happened in Milan and similar styles of projects.

[00:51:49] And hopefully they also follow through with the next sort of Barcelona-like phase now that they've got that.

[00:51:55] Now that they've shown everyone that it's OK to take a bit of asphalt and everything doesn't grind to a halt.

[00:52:01] Amazing. Brilliant. This has been such a great conversation.

[00:52:06] I really enjoyed it. Great start to my day.

[00:52:08] 8am conversation about urban greening.

[00:52:12] Any final thoughts or conclusions or anything you want to point people towards as we wrap up?

[00:52:17] Gosh, I guess I would just invite your listeners to do a little thought experiment that I do when I walk down streets because I've been doing it since probably before I knew anything about urban greening.

[00:52:31] And I don't think it needs any special expertise.

[00:52:34] But just next time you're walking down a street, notice how big the gaps are between the trees on your street and then look around at how much I've thought we've given to everything else.

[00:52:45] And just think about if you were king, if you could make the choice, would you take a little bit?

[00:52:51] Could you take a little bit? Would you maybe make a little slot along a blank wall and plant a creeper at the bottom of it so that you could have a creeper grow up there?

[00:53:00] Try and spot all the opportunities that you have right there in your street.

[00:53:05] And I'm often amazed by how much possibility there is and how I just didn't see it until I started thinking about it a bit.

[00:53:13] So I hope for some of your listeners and they see that too because it's quite an enjoyable thing to do while walking to buy a bottle of milk.