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Friday, 17 November 2017

Traffic and Auckland

One of the most interesting and absorbing parts of games like SimCity or Cities: Skylines is their traffic functionalities. I'm not exactly sure how they go about modelling traffic but I do know in the latter game a dude managed to basically have a congestion-less city by following the principles of traffic engineers. He made a guide about it... although I haven't really managed to follow it properly. Over on Greater Auckland, though, traffic engineers seem to have a... problematic reputation. And the transport patronage modelling gets a particularly bad rap.

You might remember that in one of my earliest posts here I talked about the CRL and how the then government had set completely unrealistic targets. As it turned out the unrealistic part was in how quickly the patronage goals would be left in the dust. Aucklanders, reality said, like to catch trains a hell of a lot more than the models said. GA trots out all sorts of explanations for the patronage data. New trains, positive buzz from electrification, double-tracking the Western Line, station improvements, HOP and even the New Network (for bus services) roll-out could be added in insofar as it has pushed people from some bus routes on to the trains. Most of these things have been present for some time now. The New Network is still an ongoing thing but I'm less certain it's been "blamed" for patronage growth. But still the trains grow in popularity. And still the models seem quite sceptical about public transport use by Aucklanders.

At the same time that all this has been going on I think there's been a massive surge in the normalcy of "Auckland has bad traffic". I don't really remember in the last five years traffic having received so much attention. Maybe it's reflecting a real increase in the intrusion of congestion in mundane life. Maybe it reflects that I now commute (albeit by train... this is the only reason I started reading GA after all). Maybe it reflects that I don't remember the sheer amount of complaining that I used to read about. I do know in 2014 when I was explaining the predictability of the trains was a great advantage in a semi-public fashion there was a certain amount of scepticism. I think one of the present people agreed with the notion but thought I was placing too much probability on the chance of a comparably long commute by car. I don't think you'd encounter that now. Certainly not when you only need to balloon the commute from where I'm from by 20 minutes to equal the train's journey. But even if the traffic's being absolutely psycho is a narrative only from 2017, it's still worth a quick chat about it.

Solutions to Mass Traffic Complaints

How one sees the problem will dictate the nature of the solutions that one generates. For example, if you think about the problem as being about the preponderance of very boring complaints about traffic, if everyone hardened up the problem is solved. How to achieve that might be a difficult question, but that's a perfectly reasonable solution. If, however, you see the complaints as a symptom? Well, then, that's when you start to think about things like congestion pricing... and also when you realise that, contrary to what people say about Infosys 110, it actually had some pretty useful stuff in it (welcome to the problem tree concept).

Building More Roads/Lanes

This won't work. There's a thing called Braess' Paradox which I heard about via GA and following Wikipedia it runs thus:
a proposed explanation for the situation where an alteration to a road network to improve traffic flow actually has the reverse effect and impedes traffic through it. The paradox was postulated in 1968 by German mathematician Dietrich Braess, who noticed that adding a road to a congested road traffic network could increase overall journey time, and it has been used to explain instances of improved traffic flow when existing major roads are closed.
The paradox may have analogies in electrical power grids and biological systems. It has been suggested that in theory, the improvement of a malfunctioning network could be accomplished by removing certain parts of it.
Well, okay, it doesn't happen every time but it does happen. And you can immediately see why it happens. Everyone basically thinks, "Well, it's faster now, so driving is worth my time". At the first stage, you get people who choose to drive down the new road because it's logically faster for them. This may or may not make other actors decide to behave slightly differently. At the second stage, you induce more vehicles into the network as a response to the change. This definitely does adjust the behaviour of everyone else. And so, eventually, you end up in a situation where if everyone is making their best response given what they think about everyone else's behaviour the overall outcome is actually more, not less, congestion.

(Interestingly, this is another example of a game where the Nash Equilibrium is not the best social outcome, i.e. the self-interest of the butcher and baker etc. doesn't generally lead to good places.)

Congestion Pricing

I think the basic idea here is that too many people are trying to use the road at the wrong time. That is, maybe John could get to work at 8:30, Paul at 8:00, Ringo at 9:00 and George at 7:30 but ultimately they all end up on the road at the same moment. As do all the Petes, and they could get to work as late as 9:30.

You can see how that might happen, right? You get a bunch of Pauls who think that they need to be early, so they get on the road and in the way of Georges who are aiming to arrive at their "optimal" time of 7:30. This slows everyone down, giving these Pauls an incentive to leave earlier in the day as well as the Georges. The trouble is that some Johns also want to get to work early so they enter the traffic at the right moment to be floating around with Pauls... and so on. The traffic created by the behaviour of earlier actors changes what seems to be the right thing to do for later actors. And it's all compounded by where people leave and arrive from. In real life we would leave at about 8:25/8:30 for school all the time to arrive at 8:40. On a normal day this was a journey of 3-4 minutes (40 if I walked... which I often did, at least going home), but sometimes the Great South Road was clogged with bumper-to-bumper cars at this time so we'd be late. The point is, people making longer journeys get in the way of people making shorter journeys inducing more behavioural changes.

With congestion pricing, at least if managed well, you would create incentives to leave at better times. If you priced people coming into an area during 8-9 say, you obviously discourage people who don't need to be in that area from joining the party... here, the Petes. You also create a tradeoff. The Johns and the Ringos could leave quite a bit earlier to avoid the pricing but in doing so they have massive amounts of down-time before they actually start work... which isn't desirable. And if they've got to drop off Judes on the way to school as well, they may actually be told not to have anyone at school too early in the day. Thus, Johns and Ringos have incentives to try and find other ways of travelling that avoid the pricing. In my example, it's not clear what would happen with the Pauls and Georges. I have actually made it more attractive for the Pauls to leave early... which suggests that the pricing needs to be adjusted (maybe from 7:30-9).

Now, I think I have brought up one of the issues with congestion pricing... you have to do it right. Don't get me wrong: it's definitely an attractive mechanism for reducing the amount of people travelling in private vehicles or, at least, for reducing the number of single-person vehicles. But you also need to think about the equity implications and the lessons of Braess' Paradox. That is, there are people who can afford to pay congestion prices and there are people who can't. Yet, the need to make trips into congestion priced areas is distributed across these two groups without consideration of fairness. And what about the sorts of behavioural choices we'd induce? How do best responses change? Pricing traffic entering in an area seems to me like a "soft" version of closing a road... which means that we ought to be thinking about Braess' Paradox's central point: the systemic implications of local changes. Or, in other words, doing it right is quite complex and needs to involve a certain amount of... ah... nuance? empathy?

Cost Internalisation

Another idea that I have encountered in reading GA over the last three years is the notion that automobile transport is heavily subsidised. This probably doesn't seem obvious to the consumer what with all the associated vehicle costs and taxes for roads, but it's true. Roads don't pay for themselves: they are built at and run at a (financial) loss. When you think about it, this is one of the reasons why governments are in the business of road building in the first place... it's very difficult to get a private entity to do so for a public road. But the subsidisation is broader than this. It's reflected in artificially cheap parking. It's reflected in the non-internalised health and environmental costs that car travel and resultant pollution cause. It's seen in the failure to price in the costs of all the space that cars occupy. Think of the complaints about the Ports of Auckland's waterfront carpark. That exists for every single item of car infrastructure... from your garage that could've been a house, that overly wide road that could've been part of a house, that carpark which could have been... the list is extensive.

The trouble with thinking about trying to make drivers internalise the costs of their "habit" is that there are so many different costs to internalise. Making developers pay for the infrastructure for greenfields development kind of helps, and maybe boosting some of the taxes would work too (but they'd need to be ones specifically tied to vehicles because internalisation requires seeing driving as the cause/origin/root of the costs). Charging for parking more intelligently is probably the biggie.

I know the issues with paying to park. I hate paying to park. Indeed, it's probably one of the problems I have with cities. I come from a part of Auckland where it doesn't happen at all. That's my normal. It's how I judge things. But I also know that where I live parking isn't scarce and traffic in the town centre isn't at issue. Sure, there's some traffic problems along the Great South Road these days but that's largely caused by "big box stores". In Auckland as in the CBD it's a very different matter. A hell of a lot of the trips through and to Central Auckland don't need to be made by car. Some of them probably don't even need to happen at all. This kind of traffic is what would disappear if car parking was priced to reflect the demand for parking and the social costs of parking. The trouble is what happens to the family trip to the Museum?

The Domain/Auckland War Memorial Museum is not an amenity for people who live within a kilometre of it (as seems to be the thinking of GA) but rather for all of Auckland (really, the country). And however convenient you make public transport options, visiting the Museum as a family isn't just a matter of moving prams and walkers and the like up the hill. It's not even really a question of frequency and timetabling... although, obviously, that helps. The challenge is that it costs about $10 return for a single adult to get from the outer zones of Auckland to the Museum. That's quite a lot of money... for just one family member. Pricing parking at this rate (i.e. cost equivalency between commuting and driving for the sole-worker) is one idea, for sure, but I think it really breaks down for non-commuting traffic. Going to the Museum is just one example of such a trip.

Sure I'm ignoring some subtleties here. Hell, maybe you're thinking, "But Harry, that $10 parking or whatever is spread over all family members in the vehicle," which is a good thought. A supermarket shop doesn't need to be massive shopping binge with the whole family. You could change that behaviour. Many miscellaneous trips (e.g. appointments, visiting friends) could be done differently too. But there is another truth here: $10 is a lot. If you think it isn't, regardless of whatever personal status you like to bring up in Oppression Olympics, you're privileged: $10 can be a lot of different things. Growing up we'd have never had gone to the Museum as often as we did if we had to pay $10 to park on top of everything else. And while I have mentioned my mother was often a WINZ client, there were (and are) far worse off families than us. The trouble is that preserving "free" parking for these kinds of trip is problematic... even now the Domain's roads see a lot of commuter traffic. I think, in principle, if you paid to park with a HOP card (currently not a possibility) and then tagged on with that HOP card at the amenity you could do it. Visiting the Museum, to the HOP Card, would count as a trip, and provided the time between tagging off at the Museum and tagging out of the parking was less than, say, 30min the journey as a whole would be free.

Also, if you're thinking, "But think about the people who can't afford a car, Harry". Well, hey, if it's possible, ain't no reason why that HOP card idea couldn't save you money on your last public transport trip... provided you tag on within 30 minutes and stay for at least 30 minutes. But I'm glad you raised this point, dear reader, because here comes...

Investment in Public Transport

Public Transport also doesn't solve congestion... unless you start using it. It's fairly similar to Braess' Paradox, I think. Because you get more people, say, catching a train, you create a "void" in the traffic system which people interpret as, "Hey, traffic is good enough that I can actually drive!" Which means that public transport is probably fairly traffic neutral in the long-term. Unless, as I have said, you're on it. Which you should be. Remember? Too many trips in cars that don't have to be in cars.

GA's Congestion Free Network is called such for the idea that congestion isn't a reality on the routes they plan. At the moment if you want to catch a 33 bus from Otahuhu to Manukau you're going to get stuck in traffic during many parts of the day. Why? Because those busses have very limited access to bus lanes. The Congestion Free Network's busses will be on bus lanes, the light rail will have as much grade separation and right of way as possible and the heavy rail lines will include network improvements like fewer at-grade crossings (i.e. one of track or road will go under the other). This will allow for greater reliability, especially for busses. It won't help as much with the sardines problem but more frequency and better services will spread passengers over more services rather than what can happen now where it's possible that everyone who finishes between 2:30 and 3:15 can end up catching the same train depending on walking distances.

However, even if a public transport trip is compromised by traffic congestion or the service being at capacity many of the issues of congestion are avoided. After all, you can feel like you're doing something useful like reading a book (even standing up in crowded trains this is possible) and you also avoid the stress of being the driver who gets to inch forwards only to stop suddenly. By choosing to sacrifice the control at the start of the journey, you don't suffer a loss of agency in the way that a traffic jam takes the power out of your hands does... except when something unpredictable happens (such as some prick killing themselves by public transport... there are much less selfish ways of committing suicide and what's the point of writing a blog on the internet if you can't be insensitive). To be honest, that may even be okay as long as you get told what is going on (which is not something AT is good at, like at all... they are, in fact, terrible at customer updates).

The reasons to invest in public transport have little to do with easing or avoiding congestion. If that's the private benefit you personally get from it then power to you... I'm not here to take away that personal victory. We want to invest in public transport for a bunch of reasons. I've talked before about the choice angle. I obviously believe in the equity angle. But public transport is also a great way of pedestrianising urban spaces. That's great for shops. That's great for health. That's great for the feel of the city, which is good for tourism. Public transport (despite its ability to enable sprawl) also helps cities develop density which is good for the economy, house prices and environmental sustainability. After all, if you don't need to use a car, you don't need as many car parks and you can have smaller roads and so on. And of course it does matter, on some level, that the man on the Clapham Omnibus doesn't experience congestion. (I'm hilarious.)

Density & Broader Systemic Change

Wait, didn't I just talk about this? Well, yes, but that was more a mention. I feel like there is more I can say about density... in particular its relationship to systemic change, which I feel is a topic we've been dancing around since I brought up Braess' Paradox.

The thing with Auckland is that it's not a particularly dense city. I remember talking to a German au pair once who was explaining how it seemed odd to her/her parents that moving 30km away left her in the same city. I'm not sure that's an entirely rational point of view given that Auckland's area is a lot smaller than a lot of places, but it does give perspective. And the perspective that it should be giving is that Auckland is an inefficient user of space. In fact, NZ as a whole is inefficient if all these people who claim to care about population growth feel NZ is a full country. Good God. This is a place the size of the UK and Japan with a population oh so much smaller. 20 million people could fit here easy. But only if we start seriously waking up to the possibility of about 7 million people in Auckland. To do that now I daresay would solve my problem with Wellington... it'd just be a jumped up suburb rather than a city in its own right.

With density Auckland would be a very different place. One of my friend has a habit of looking at Auckland and wondering where all the tall buildings are. I kind of agree. Somewhere I have a photo of Auckland that shows the ports cranes... as a major part of the skyline. I don't think that should happen. Auckland would benefit enormously by having density radiate out from its suburban train stations. I live 10 minutes from a train station. There isn't even a two-storey house anywhere near me! These sorts of areas would gain a lot from having human-scale density. That's terraced houses and buildings no more than 7 storeys tall and the like. Sure, there'd need to be improvements in the bus network and maybe a couple more public spaces... perhaps involving a metro school type situation... but I am suggesting radical change here.

Density brings more people and with the way things are now that would mean a lot more cars. But if you didn't build places with the expectation that every resident could have a vehicle then you'd help normalise not owning a car. Here Google reminds of a Discworld quote from Moist von Lipwig, "Make the change happen fast enough and you go from one type of normal to another." In other words, expectations are a product of conditions. (Trouble is it works the other way round too.) But density also enables more public transport... and different types of it too... and helps facilitate making walking are more visible part of mundane life. This would normalise... that's right! other kinds of not driving behaviours. I remember when Chloe Swarbrick was gunning for mayor... someone suggested she would make a poor mayor because her friends catch busses (I'm pretty sure in a comments section). Perhaps the most important change that density would bring is in the way space is visualised.

This semester I've been taking Geography 104G (Cities and Urbanism) and while I have broadly been disappointed with what is an arbitrary and capricious course a lot of the readings have been really interesting.1 One of the ideas that those readings drive home is how automobile-centric cities are and urban planners' modes of thought have been (and possibly still are). Obviously these ideas did arise in a situation where cities were dense but I think if you had a space that didn't look like it was intended for a car you'd end up with a sort of disconnect. The idea here is that if you stop designing for cars, and assist this through density, you'll end up improving traffic for cars... because you will have fewer cars on the road. If you don't induce the demand, you don't induce the demand.

Also, if you've got a dense city, you physically don't have to drive places... you can walk to your destination so much more easily.

Better Driving

Bad drivers cause traffic jams. Not because they're causing accidents (obviously they do) but because they're bad. If you can stop a friend from driving badly, legend. Shame there isn't really anything else we can do to improve driving.

Concluding Remarks

I don't want to be that guy so I'll be that guy anyway: save the cheerleader from being stuck in traffic, save the world. The stakes are pretty high when it comes to traffic. Perhaps not as high as saving the world, but the fumes from traffic jams certainly doesn't help anyone. So maybe. But we need to seriously think about how we're creating traffic and what exactly the problems with traffic are. Luckily I'm not the only one talking about this. Here's an example of a piece with a much wider audience (sadly). It's got less detail on more options! More! Less! At once! Exactly what we want to achieve. More not driving is fewer bad driving experiences. Fewer cars! More movement! The trouble is, as we discussed, when you make driving better, you make people want to drive more. So you have to do it all. No half measures. Well, okay, here's my action order (for my list):

  • Phase One: Don't build roads. Price parking appropriately. Continue improving public transport. Allow for Density.
  • Phase Two: Accelerate Public Transport investment. Bring in Congestion Pricing.
  • Phase Three: Get ambitious with public transport. Enjoy benefits of density.

Remember, I'm talking about Auckland.

Partly because they are interested in "save the world" moralising... lecturers if you don't want students to write such things, give them different readings and completely change the third section (this is what I mean by arbitrary). Hey, look, another application of this expectations/conditions dialectic (God that course loves that word).

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