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Comment by mktmkr | Hacker News Reader

The cars are the reason the buses are slow. 22% of LA workers travel to work without a car, which isn't great but it's not zero either. Metro LA added a dedicated bus lane on Flower and they are moving more than one bus per minute in that lane. As soon as you remove the cars everything else gets a lot better.

https://twitter.com/metrolosangeles/status/11538072082299576...

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Are they? It's always seemed to me that frequent stops, circuitous routes and long travel distances are the reason the buses are slow relative to cars. After all, cars have to deal with other cars as well. And for comparison, to the south, San Diego has much better traffic than LA, but the buses are still quite slow (e.g. I recently considered taking the bus rather than a 15-minute drive in San Diego, but it would have been over an hour by bus).

Buses have to stop to be useful. Any theoretical bus route will be circuituous for some subset of users.

The solution to these issues is to provide bus signalization, dedicated lanes, and/or queue jumping opportunities. These changes minimally inconvenience cars while significantly speeding up buses. It makes it so that a bus route, while longer, can be time-competitive with driving (or rather, closer enough that it overcomes the inconvenience of walking to/from stops and sometimes having to wait for your bus)

You guys are both right. Removing cars from a bus lane makes the buses go faster.

And having frequent stops makes buses go slower.

Traveling long distances doesn't make the bus any slower; it just limits the frequency you can revisit a stop on the route without increasing the number of buses on that route.

I didn't mean long travel distances make buses go slower, I meant they amplify the disadvantages of buses, and America tends to have a lot of distance between things. If a trip would take one minute and it takes four instead, that's probably fine. If a trip would take 15 minutes and it takes an hour, that's a bigger problem, even though it's the same relative slowdown.

I have exactly that problem:

- Motorcycle to work: 15 - 20 minutes door to door (driving generally ~30 minutes, but 40 minutes or so during busy periods)

- Bus to work: > 60 minutes (7 minute walk, 5 minute wait, 45 minute average bus journey, 7 minute walk)

Cycling would, I reckon, take me about 45 - 50 minutes door to door until I got fitter, but that would be fine because I'd be getting loads of exercise, so the trade-off becomes worthwhile even though it takes longer. (The reason I don't cycle is there's no safe route.)

Presumably it just depends on whether the road is congestion. Roads are essentially non-rivalrous (my use of the road doesn't reduce your ability to use the road), until the road is congested.

Presumably most congested roads are used mostly by cars, so I suppose you could say that "cars cause congestion and congestion makes buses slower." But of course, the congestion also makes the cars slower as well.

There are different bottlenecks in buses depending on the situation, and I'm not familiar with LA. However, the places where I've tried using the bus, the latency involved in walking to the bus stop, waiting for the bus, getting off and walking to the transfer bus stop, waiting for the bus, then walking to my destination far exceed the delay added the stops the bus had to make. In many cases it exceeded the total time on the bus altogether. Increasing the frequency that buses run a route has huge impact on travel time, but there is a limit as to how much you can do that without adding a dedicated lane. The small improvement in speed caused by not having to deal with cars is just icing on the top.

I was pleasantly surprised with LAs bus system the last few times I've been. They have both express buses and ones that hit every stop. I also find LA to be very walkable.

Shouldn't the busses themselves end up removing cars from the road?

Removing parking spaces puts more cars on the road -- circling for spots and parking illegally in traffic lanes.

If you want faster buses, evict the cars from the bus travel lanes.

Yeah, except no. This is just one of those tropes that motorists use to force cities to subsidize them. Every study on this topic has conclusively shown that parking causes traffic. The construction of parking precedes the worsening of traffic, the amount of parking built is proportional to the amount of traffic observed, and the reverse process is also observed to correct the problem: removing parking alleviates traffic congestion. The case that parking causes traffic congestion is as strong as the case that smoking causes lung cancer.

Hey, do you have anything handy to support this? I can totally do my own research if it's hard for you to recall your sources. Just hoping for a quick lead or two. If you roughly remember the title of the papers or the names of authors or the regions studied, anything at all, it'll help me search faster and I'd be mega grateful.

Construction of parking preceding the worsening of traffic is not the same as parking construction causing traffic congestion. Adding more servers behind a load balancer will also precede congestion on your network. Because you've increased your capacity to service additional throughput, but did not increase your network link to handle that higher throughput. So at some point, it'll start thrashing.

Same with parking. You build parking in areas where you anticipate increased demand or already have unmet demand. By building parking, you increase your capacity to meet that demand.

If you have unmet demand (i.e. not enough spaces for the volume of vehicles that wish to park in an area), you're limiting the economic throughput of that area. Yes, you're reducing traffic congestion in the process, but at a very real economic cost for those whom were being patronized by that now-gone traffic.

Same with anticipating new demand. If you're building in an area, you want to be sure the area has enough parking capacity to absorb the intended volume of people traffic your building will have. If you're building a new skyscraper or mall or big box store, that's likely not true. So you incorporate parking into your project. Once your building (and parking) come online, you'll start attracting a higher volume of individuals to an area. Which, except for the most underutilized or mature transportation networks, will have a corresponding impact on congestion due to the greater throughput of individuals to the area.

If you have mature public transportation, then your transportation network likely has the bandwidth to absorb this throughput increase with a lesser impact on congestion than if you're in an area with immature public transportation options. But mature public transportation tends to be very expensive to build and maintain. Which is only likely to happen after growing to the point of having heavy enough congestion to make such expensive and regionally disruptive changes both politically palatable and economically feasible.

I do not envy urban and transportation planners.

If you want faster buses, evict the cars from the bus travel lanes.

That's hard to do without BRT - we have plenty of dedicated bus lanes (the right lane) around here, but they all allow cars for right-hand turns, so buses still get stuck behind a line of cars.

Without BRT and center-island boarding, it's harder to reserve anything but the far-right lane since the bus needs to get there to pickup/dropoff passengers.

> That's hard to do without BRT - we have plenty of dedicated bus lanes (the right lane) around here, but they all allow cars for right-hand turns, so buses still get stuck behind a line of cars.

Dedicated bus signalization, no right turn on red, and cars perform right turns from the second lane. Dedicated signal phase can be combined with separated bike lanes to improve safety for other road users, as well.

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