[mcv]

Self-driving cars still take up space on the road. Even more than human-driven cars, because now there will also be cars transporting 0 people. It's going to make congestion worse. Public transit is the solution to congestion. Well, one of the solutions, because bikes are probably a better solution for most people: they do start in front of your home, can park anywhere, and don't cause congestion the way cars do.

We're talking about cities, of course; in rural areas, nothing beats cars.

[cyberax]

> Self-driving cars still take up space on the road

This is a false argument. Think about this: a bus every 10 minutes is effectively 500-900 meters long! It easily "takes" as much space as 100+ cars. In other words, nothing would change from the traffic perspective if instead of 1 bus every 5 minutes, you had 100 individual cars.

The "people in the shape of a bus" argument makes sense only when you're talking about the performance in a very narrow case of transporting people in a steady, uninterrupted stream of buses. Or if you need to size your traffic bottlenecks.

Moreover, a bus route necessarily is unoptimal for at least some people on a bus. They are effectively "thicker" than other people because they take up more "effective space". But wait, there's more! Buses also necessarily move slower due to stops, so the "effective length" of a bus becomes even longer because cars will clear the road faster.

But wait, there's even more! A single bus needs about 3 drivers to be effective. So with the average daily busload of around 15 people, you have almost 20% of the bus taken by the drivers on average. This makes bus trips pretty expensive. Not quite to the level of Uber/Lyft, but surprisingly close.

And these problems are fundamental. That's why urbanists like NJB don't like to talk about that.

[mcv]

Nothing about this addresses NJB's argument that self-driving cars take up more space than regular cars, because there will now be cars with 0 people in them.

Ultimately the thing you want to transport is not cars, it's people. Walking fits the most people in a limited amount of space, then bikes, buses and other forms of public transport, then cars with 4 people in them, then cars with 3 people in them, then cars with 2 people in them, then cars with only 1 person in them, and finally empty cars. More cars will never reduce congestion.

But to address your point: A bus in a dedicated lane takes up more space than a bus that's stuck in car traffic, you are right about that. On the other hand, when congestion is so bad that cars simply don't move, no matter how many lanes they have, getting people out of cars into more efficient forms of transport, will also help cars. And a bus that actually goes, can do that. If you look in cities with good public transport, more people go by public transport than by car. In cities with good bicycle infrastructure, more people go by bike than by car. That means even cars are less likely to get stuck in traffic in those cities. Even if you take away a car lane.

I don't know where you got the idea that a bus needs 3 drivers.

[cyberax]

> Nothing about this addresses NJB's argument that self-driving cars take up more space than regular cars, because there will now be cars with 0 people in them.

And? There are also buses that trundle around with nobody but the driver in it. Or unused bikes and e-scooters that litter the sidewalks.

> Ultimately the thing you want to transport is not cars, it's people.

Yeah. And let's make it efficient. Put these people into 3-level bunk beds. This way they can travel all together in just 1 bus to their assigned workplace. And you don't need to run buses until they're allowed to clock off their shift.

Efficiency!

> On the other hand, when congestion is so bad that cars simply don't move

In this case you close the downtown offices and force them to work on alternate days, like they do in India with cars. Remote work already can replace 70% of all work, and with AI this number will grow.

Apart from that, mild carpooling will decrease the number of cars by 2x. Small vans with 6 seats can _easily_ remove all congestion.

> no matter how many lanes they have, getting people out of cars into more efficient forms of transport, will also help cars.

Just one ask for urbanists. Can you just stop lying, please? Just one thing. Don't say that "transit help cars". It doesn't. There is a lot of research from _you_ (e.g. https://archive.strongtowns.org/journal/2020/1/7/does-buildi... ) that proves this. Transit does NOT decrease the travel time for cars ("traffic") it _increases_ it by increasing congestion due to increased housing density that transit forces.

You want to pack people into 3x3 jails ("microapartments")? Fine. But be honest about it.

[yunwal]

> a bus every 10 minutes is effectively 500-900 meters long!

uhhhhhh what. What does every 10 minutes have to do with this at all

> It easily "takes" as much space as 100+ cars.

are you ok??? have you seen a bus before??

> A single bus needs about 3 drivers to be effective

I have never ever seen a bus with 3 drivers in it. If you're talking about 3 drivers over the course of 24h, those drivers are not in the bus at the same time, and therefore don't make up 20% of the passengers on the bus. If you're saying the average bus route serves 15 people per day, you are certainly mistaken.

[zimpenfish]

> If you're saying the average bus route serves 15 people per day, you are certainly mistaken.

Definitely mistaken for London - currently (according to DFT's numbers) about 18 people per bus average (not per day, though.)

[cyberax]

> uhhhhhh what. What does every 10 minutes have to do with this at all

See the word "effective". Think about the road space that a bus requires but doesn't use if it is just once per 10 minutes.

> I have never ever seen a bus with 3 drivers in it. If you're talking about 3 drivers over the course of 24h, those drivers are not in the bus at the same time, and therefore don't make up 20% of the passengers on the bus.

Yes, I'm talking about the drivers that are needed for a reasonable 16-hour bus service. And the typical ratio is actually a bit more than 3 drivers per 1 bus.

> If you're saying the average bus route serves 15 people per day, you are certainly mistaken.

No. I'm saying that on _average_ there are 15 people in a bus. More during the rush hour, fewer during the off-hours.

[gbbgbbgbb]

> See the word "effective". Think about the road space that a bus requires but doesn't use if it is just once per 10 minutes.

Excepting the case of a dedicated bus lane, the amount of road space a bus is preventing other cars from taking up at a given time is equal to the size of the bus. Technically, it's less than that in the case of bus stops littered amongst parking. In the case of a dedicated lane, it reduces the maximum throughput of the thoroughfare, but it's not a simple thing to model as there are other effects that the bus can have to reduce the number of cars when the rate limit of thoroughfare would be pertinent (i.e. usually rush hour). Just saying "think about it" when saying a bus takes up the space of 100+ cars doesn't really substantiate such a bold claim.

> Yes, I'm talking about the drivers that are needed for a reasonable 16-hour bus service. And the typical ratio is actually a bit more than 3 drivers per 1 bus.

> No. I'm saying that on _average_ there are 15 people in a bus. More during the rush hour, fewer during the off-hours.

If there is an average of 15 passengers on the bus during the operations of the bus and there is an average of 1 driver on the bus during the operations of the bus, then it is 1/16th occupied by driver(s). For it to be taken 20% by driver occupancy, then it would require there to be an average of 4 passengers on the bus during operations.

[cyberax]

I actually am citing the traffic engineering handbook, the section about computing the efficacy of bus lanes. And I'm using deliberately conservative estimates.

> If there is an average of 15 passengers on the bus during the operations of the bus and there is an average of 1 driver on the bus during the operations of the bus, then it is 1/16th occupied by driver(s)

No. For the bus to be viable, all 3 drivers have to be "virtually present" there. A bus _has_ to be available at all times with a reasonable interval, otherwise it might as well not exist.

Or in other words, a passenger needs to be paying the salary for even the missing drivers.

[gbbgbbgbb]

> I actually am citing

until this moment, you were only claiming.

> the section about computing the efficacy of bus lanes

> Excepting the case of a dedicated bus lane

Not all buses require a bus lane. A bus lane is a deliberate choice that doesn't make sense in all areas and for all bus routes. It is disingenuous to reference the reduction in throughput due to a bus lane as a blanket claim that an individual bus takes away the room of 100+ cars on the road.

> you have almost 20% of the bus taken by the drivers on average

> No. For the bus to be viable, all 3 drivers have to be "virtually present" there.

Your claim is about how much of the bus is taken by drivers, which while having some correlation to cost, really doesn't have anything to do with the cost of operating the bus. An oversimplification of this is to posit a magic bus that runs 24 hours a day with 8 hours shifts by 3 drivers. That means that the drivers take up 24 person-hours of capacity on the bus. If we say they have 15 passengers on average, then the passengers take 360 person-hours of capacity on the bus. Thus, drivers take up 24 / 384 or 6.25% of the capacity.

Honestly, I never really cared enough to convince you that transit is a good thing because that feels like a fool's errand. But these weird claims and fallacies bother me. If you want to claim that a bus isn't cost effective, then great. Just cite an actually relevant metric and actually calculate it correctly.

[yunwal]

So where is the 20% of passengers are drivers thing even coming from?

[cyberax]

3/(3+15) = 3/18 = 1/6 ~= 20%

[yunwal]

Only 1 of those 3 drivers is on the bus, sorry!

[ErroneousBosh]

> We're talking about cities, of course; in rural areas, nothing beats cars.

Where I grew up in NW Scotland, it's a five hour round trip to go to the supermarket. You pretty much need a car for that.

Where I live right now it's a five minute walk to the supermarket, but I still need a car because the things I work on are a long way from where I live, often up steep muddy mountain tracks.

When I lived in the middle of Glasgow people used to come up and have a go at me about driving a massive V8 4x4 in the middle of a city. What am I supposed to do with it? Bike to the suburbs and then go and drive up a mountain?

"But why not get a job where you don't need to drive hundreds of miles in a massive 4x4?"

Because then the things on the tops of mountains don't get fixed when they break, and the radios don't work properly, and then people like you die in a fire.

Sometimes it's hard for people to grasp that just because their not-really-a-job tapping numbers into an Excel spreadsheet all day can be done from home or from an easily walkable city centre location, it doesn't mean that everyone's job looks like that.

I do wish I could usefully use a cargo bike. Those things are awesome.

[sensanaty]

What people really misunderstand in these discussions is that no one is talking about completely killing off driving as an option, and no one says that public transportation works in literally 100% of circumstances.

We just want there to be viable public transportation options for situations where it makes sense. This even makes it easier for the people who do have to drive, like you, as there will be less congestion because a single bus can replace literally dozens of cars, combine that with a single tram and a single metro car and you're replacing literally hundreds of cars that would otherwise be on the roads instead.

[ErroneousBosh]

Exactly. It would be awesome if we had viable public transport options in rural areas too, although necessarily they would not be as frequent of flexible as in cities. There wouldn't be the requirement for them so much, because of the lower population density and the different patterns of vehicle use.

But growing up in a rural area where there are two buses a day none of which are useful for anything other than high school pupils (although they're not school buses) it does tend to limit everyone's options.

[cyberax]

> What people really misunderstand in these discussions is that no one is talking about completely killing off driving as an option

I find this statement utterly hypocritical. Sure, we're not killing off driving. We are just choking off the roads with bike lanes, forcing extra-high density ("just build more"), removing parking, forcing the drivers to pay for transit that they don't use, and just to pay in general.

But no, we're not preventing driving. Not at all.

Urbanists want to stop people from using cars as much as they can force that.

[gpvos]

If you actually had to pay a proper price for your parking space, which is currently heavily subsidized, you would suddenly consider taking public transit instead, even if that were priced at actual cost.

[ErroneousBosh]

In what way is a piece of ground I own "heavily subsidised"?

[gpvos]

Well, you're parking it in other places as well, I assume, unless you're only making pleasure rides with no stops at all. I am speaking more generally than just about your particular situation, which I obviously don't know. But in case you live in an American suburb: their entire financial setup is unsound, which arguably means even your own ground is subsidized. I find the arguments of Strong Towns and Not Just Bikes quite compelling: https://www.youtube.com/watch?v=7Nw6qyyrTeI .

[ErroneousBosh]

> Urbanists want to stop people from using cars as much as they can force that.

If you live in a city, you probably don't need a car.

[sensanaty]

You call it "choking off" roads; I call it basic geometry. Reallocating a lane of traffic to bikes or transit moves exponentially more human beings through the exact same amount of physical space. But sure, pretend that a single occupant dragging around a 4 ton metal box to buy groceries is the absolute pinnacle of spatial efficiency.

And the fact that you're complaining about "removing parking" is hilarious. Street parking is objectively the most useless, wasteful allocation of already limited public space imaginable. You expect cities to dedicate premium real estate to act as a subsidized storage locker for your private, empty vehicle for the 95% of the day you aren't even using it. Then you complain about non-drivers "forcing" you to pay for transit, while everyone else's taxes are literally subsidizing the free public storage of your personal property.

Let's also talk about your entitlement to those roads. When you complain about "choking off" streets, what you're really whining about is that cities are finally prioritizing actual residents over commuters who are just driving through. Most car traffic in urban centers is just people transiting. Why should a neighborhood sacrifice its safety, noise pollution levels, air quality, and public space just to act as a high-speed shortcut for people who don't even live there?

And please, spare me the inevitable "but what about rural areas" argument. We are talking about dense cities. Nobody is coming for your car in bumfuck nowhere; you can keep driving there all you want. (Though honestly, here in the Netherlands, you don't even have to drive in the countryside because you can usually just grab a train or get anywhere by bike, but that's beside the point.) Urban planning applies to urban areas.

I live in the Netherlands. Millions of people here take transit and ride bikes every single day. And guess what? Nobody banned cars. In fact, it's widely considered one of the best places in the world to drive specifically because everyone who doesn't want or need to drive isn't forced to be on the road getting in your way. We just realized that sacrificing huge swaths of our cities so commuters can treat our neighborhoods as a shortcut is incredibly stupid, and there are infinitely better ways of using the limited space in cities than to let drivers park their cars there.

Giving people viable choices isn't a totalitarian conspiracy to oppress drivers, it's just good urban design. It's wild that you are so used to forced car dependency that simply offering people an alternative feels like a personal attack.

P.S., I'm also a driver, I just don't need to do it 90% of the time because I live in a sane country where I can just bike to the other side of the city in 20 minutes.

[cyberax]

> Reallocating a lane of traffic to bikes or transit moves exponentially more human beings through the exact same amount of physical space.

Except that bike lanes in the US, on average, carry fewer people than car lanes that they replaced. So yes, it's indeed "choking off". It's done to force the density increases. After all, if you can't commute anymore (roads are sabotaged and transit is slooooowwww), you'll have an option to live closer to the workplace. In a new expensive apartment in a high-rise.

Bike lanes also kill businesses. There were studies showing otherwise, so I replicated them, and they now show the opposite. Places in Seattle and Portland with bike lanes that displaced traffic lanes are declining faster than areas around them. The previous positive results were caused by spurious correlations during the general upswing in the urban economy after the 2008 crisis.

> Then you complain about non-drivers "forcing" you to pay for transit, while everyone else's taxes are literally subsidizing the free public storage of your personal property.

There is no free parking around me anywhere. And I'm also paying around $2000 a year in car tab and property taxes for transit that I don't use. And before you ask, in my state user fees pay for 90%+ of the total road maintenance expenses.

> We are talking about dense cities.

Yeah. They need to be _de_-densified in the longer term. But even dense cities will benefit from removing bike lanes and adding self-driving taxis.

> I live in the Netherlands. Millions of people here take transit and ride bikes every single day. And guess what? Nobody banned cars.

I got my driving license at the age of almost 30, and I lived in several large cities. And I _also_ lived in Amsterdam. People ride bikes in Amsterdam because there usually are no other comparable options. Transit typically takes ages longer, and car parking is non-existant. Of course, people justify that by telling themselves how they love to ride bikes even in cold wind and rain.