5 ms·

How we can reduce traffic congestion? 1. Extensive support of public transport: metro, tram, dedicated bus routes (separate from car traffic), dedicated paths

by trymas 3mo ago

How we can reduce traffic congestion? 1. Extensive support of public transport: metro, tram, dedicated bus routes (separate from car traffic), dedicated paths for bicycles. 2. ... maybe whatever is this ... UPDATE: here's a good graph - https://en.wikipedia.org/wiki/Public_transport#/media/File:Passenger_Capacity_of_different_Transport_Modes.png https://en.wikipedia.org/wiki/Public_transport#/media/File:P... , i.e. car traffic is often congested because of inherent low passenger bandwith. If google wants to manage traffic as internet routing - why then stick with outdated low bandwith ethernet cable?

ChadNauseam 3mo ago
We definitely need more metro, trams, bus routes, and bike paths. I especially want the latter because I bike to and from work every day. However, I have to wonder about the cost of these projects. In SF, we recently spent $346 million on the Van Ness Improvement Project, which added 2 miles of bus lanes. I just can't see how that's a good use of funds. If someone gave me $346 million and told me to improve society, I could think of many better options than adding two miles of bus lane. So a prerequisite to the whole idea seems to involve solving whatever is making these projects so expensive.
- fragmede 3mo ago
  Okay, how would you spend $346 million?
  - ChadNauseam 3mo ago
    If we had to stick to transportation-specific improvements, I would use the money to eliminate bus fare for a year. (muni generates about $100M in fare, so really it would be enough money to eliminate fare for ~3 years.) Unlike subway fare, bus fare doesn't prevent n'er-do-wells from getting on the bus (they just ignore the fare and get on anyway), and it probably increases ridership and gets some people out of their cars, which reduces congestion (public benefit and therefore deserving of government subsidy).
    - bluGill 3mo ago
      Why not use the money to make bus service better? There is no city that can't effectively use many more buses. Bus riders all put service as their biggest problem over the cost.
      - ChadNauseam 3mo ago
        Improving service is much better, but the relative scales here are crazy. She options are "completely eliminate cost" or "slightly improve service in one two-mile stretch". Granted, 10 million trips a year go through that two-mile stretch that was improved, but that's just a small fraction of all bus trips in SF.
        bluGill 3mo ago
        It is more than that, but even still we should as that would help the people who ride their routes. In almost all cases this would bring in more riders who find the new service good enough that they can stop driving.
  - taneq 3mo ago
    Where I live, I’d spend it on increasing parking availability at train stations, and/or run a lot more local buses that do a small (few kilometres) circuit around the station and ferry passengers to/from the station. Taking a bus to the station currently adds an unreasonable amount of time to the journey. It doesn’t matter how good trains are if I don’t live near a station and I can’t get there.
- trymas 3mo ago
  One of the problems indeed. Though IMHO it's just lack of political will. Highways are built at (relative) ease, no matter the cost. Data centers are infamously now being built at society expense (electricity and water capacity), sometimes literally in peoples backyards. At the moment I don't have the receipts, but from anecdotes - it's all just political will. There's a highway extension? Some properties are taken by eminent domain, some other NIMBYs are told to just suck it up. Data center? Forget about it - foundations are being laid this moment (sometimes no matter the law)! High speed rail? We must listen to every NIMBY on the proposed path, hence it will take 200 years to listen to all complaints and align opinions of the people impacted. Millions speant on "research, enviornmental impact and public opinion" - project stalls and is closed after 5 years. NB: I am not from USA, I think this pattern fits many (especially western) countries. Successful projects (I repeat myself) are always based on political will, when rule/law framework is designed to make such projects easier and much cheaper. NB2: Also as with anything - when you start building you get experience and expertese - the more you build the cheaper it gets. A lot of places havent built new train/metro/tram line in decades - hence all expertese must be built from scratch (from policies, to government clerks knowing how to deal with such projects, to construction businesses who never built rail in 50 years, etc.).
  - Tade0 3mo ago
    > Highways are built at (relative) ease, no matter the cost. It's like that because it's a misconception that highways are built for passenger cars. They're built for freight and all kinds of business activities - regular people using them are just a bonus. The majority of petroleum-based fuel, wear and tear on the highways and toll revenue comes from everything but passenger cars on highways.
    - jcranmer 3mo ago
      Almost all of the new highway construction is for passenger cars. Yes, the interstate highways were built in part to facilitate intercity truck traffic, but the reason for building yet another beltway around, say, Houston isn't for trucks but for all of the passenger cars in the region that are congesting the roads.
- gsliepen 3mo ago
  > However, I have to wonder about the cost of these projects. A very good way to deal with this is to recognize that all infrastructure needs maintenance and periodic replacement. Once it is time to replace a road, that is when you change it to include bike paths, bus lanes and so on. You need some foresight, planning, make new road designs part of law, and political will. Some countries have made this work very well.
- inigyou 3mo ago
  This feels like an instance of America being unable to build things due to corruption. Two miles of any lane shouldn't cost over a hundred million dollars per mile. Repainting a lane should be vastly less and even if they're building a new flyover just for buses it shouldn't cost that much. Something is happening there. It is not getting built in an effective way.
  - queenkjuul 3mo ago
    Can almost guarantee that project involved much more that just bus lanes. I don't believe even California can spend that much on paint. (And it did, the entire roadway, sewer, and water mains were replaced, traffic signals were replaced, etc: https://www.sfcta.org/projects/van-ness-improvement-project https://www.sfcta.org/projects/van-ness-improvement-project)
- Cthulhu_ 3mo ago
  The challenge that "developed" countries / cities have is that there's already a lot of existing (and aging) infrastructure around. Meanwhile in other countries they build new cities from scratch, including infrastructure based on current-day knowledge of how these things pan out long term. I think the US has the space and funds to do so. If they were to build a new city from scratch for the next 250 years, what would it look like?
wwind123 3mo ago
Also...allow people to work from home more. During the Covid pandemic, most white-collar employees work from home, and the commute and the traffic is usually not a big problem. But now more and more companies ask employees to go back to office, and traffic jam is becoming a headache again.
- rob74 3mo ago
  Yup... hours of commuting time just to sit in Zoom/Teams/Slack/whatever calls while in the office instead of at home makes no sense at all, and is bad for the environment (even if you use public transportation, not going to the office still emits less CO2 than going there). But because RTO is just a way of trying to get rid of employees without severance costs, these and other points will invariably fall on deaf ears...
- gampleman 3mo ago
  I wonder if a very small tax for RTO (perhaps with exemptions for manual jobs) would do the trick? I think it would help with making companies handle that externality.
  - Ntrails 3mo ago
    > I think it would help with making companies handle that externality. This is backwards, companies do not choose where employees live. Employees do. That they choose to live with long and unpleasant commutes (typically in exchange for more space, cheaper housing etc) is in general terms on them not the company. I'll allow that the rowback of wfh from a previously fully remote job is on the company - but certainly outside of that I have little agreement.
    - inigyou 3mo ago
      Companies as a collective also choose the geographical distributions of offices and housing and the price of each.
    - Cthulhu_ 3mo ago
      While true, there's (often, not always) an inverse correlation between location of work and cost of living. Few people can afford to live close to the office. What would work (at least in my country, and in my head / from my armchair) is sattelite offices. I live in a neat suburb with an industrial estate with some office buildings, if my job opened a sattelite office there I would be much more inclined to go to the office. But then, they would need to make sure that only people that live nearby go to that office. Given that a lot of teams are multidisciplinary, that would be difficult. Plus, the job would need to offer long-term stability, and only few jobs in software can promise stability for more than a year. If they want people to move close to work, it has to be both affordable and guaranteed stable for at least 5-10 years. I looked into it once, there was an office for a software company across the street and I applied there. But the two offers they made were both lower than what I was earning at the time, to the point where I wouldn't be able to live there. And second, after the pandemic they closed the office and became a remote-first company.
rob74 3mo ago
Yes - when I read "both navigation users and non-users share the advantages of decongesting targeted segments", I wondered how long these advantages would last. It's widely accepted that less congestion will encourage people to travel by car more, which will soon eat up the gains (https://en.wikipedia.org/wiki/Induced_demand#Definitions https://en.wikipedia.org/wiki/Induced_demand#Definitions)
- AnthonyMouse 3mo ago
  > It's widely accepted that less congestion will encourage people to travel by car more, which will soon eat up the gains This is not only not widely accepted but extremely misleading. The nature of "induced demand" is really that congestion suppresses demand. Which behaves in an entirely different way than the name implies. If demand was being induced then all attempts to relieve congestion would be permanently impossible, which is nonsense. There are empirically places with less traffic congestion. Whereas if demand is being suppressed then an apparent capacity shortfall in the amount of 0.5X may really be a shortfall of X. Adding 0.5X then doesn't work, because congestion will remain until you add X, with the suppressed demand filling back in to the extent that you satisfy it. In order to relieve the congestion you have to add enough capacity to satisfy the demand that would exist in the absence of congestion, which is more than the amount that exists now, but not an infinite amount that unconditionally consumes all possible capacity or efficiency increases.
  - inigyou 3mo ago
    There's a related paradox - I don't remember the name - that the speed of traffic is determined by the speed of public transit. Cities with less car congestion probably have faster public transit.
    - AnthonyMouse 3mo ago
      That doesn't seem like a paradox at all. If you have more convenient public transit then more people use it. If more people use it then there is less traffic. This is also why things like bus lanes are ridiculous. The theory is supposed to be that making the bus faster than cars will get more people to use it. But if that actually created a benefit that exceeds its cost, i.e. got more people to take the bus than the wasted capacity of not allowing cars to use that lane when a bus isn't, then it would reduce the traffic congestion that it inherently requires. It's a thing that can't even be part of the solution to the problem because any means of actually solving the problem would eliminate its mechanism of operation.
AnthonyMouse 3mo ago
> here's a good graph The trouble with this graph is that it assumes the buses/trains are full. It obviously doesn't apply to a bus with one passenger on it, which takes up even more space than a car. From which we can observe the problem. Alice is at home and wants to go to work. She travels along a low density street for a few miles, enters a congested thoroughfare for a few more miles, then travels along another low density street to her destination. She can't take a bus at the endpoints because she would be the only one on it, but if she took a bus only on the congested thoroughfare then she'd end up on the far side of it without a vehicle to get the rest of the way to her destination. To fix this the thing you need before mass transit (by several years) is zoning rules that allow higher density construction in a higher percentage of the land area where people live and work.
- aqme28 3mo ago
  I believe this is based on actual average usage, not by assuming the vehicles are full.
  - AnthonyMouse 3mo ago
    Which would be even worse, since existing mass transit is naturally concentrated in the places where it can operate with high capacity, and it thereby has a higher existing average than passenger cars. Lots of mostly full commuter trains, not a lot of 8-passenger SUVs that actually have 8 passengers. When the the proposal is to add more mass transit, it would then have to go in the places it currently isn't, i.e. the places where it would have to operate at lower capacity. Which leads to the problem described.
- trymas 3mo ago
  > The trouble with this graph is that it assumes the buses/trains are full. It obviously doesn't apply to a bus with one passenger on it, which takes up even more space than a car. IMHO it's a bit moot to delve into extremes. Average car occupancy is around 1.5 passengers. I'd bet that such number is far from average for average bus/train/tram/metro. I also probably won't make a mistake stating that "Average car" in USA is either a very big SUV or even bigger "truck" (which probably has a footprint as half of a bus). You also need to park your car somewhere at the destination. I also thought that there will be reply like yours, though you answered your own problem: > To fix this the thing you need before mass transit (by several years) is zoning rules that allow higher density construction in a higher percentage of the land area where people live and work. Of course you don't want to build trams and all in low density (and low population) areas and my comment didn't apply for such case. You must have density as well as mixed use zones. I am not from USA and seemingly prevalent single use zoning[1] is very foreign to me. It all comes down to efficient urbant planning. [1] correct me if I am wrong on this.
brikym 3mo ago
I think most people get that non-car forms of transport is denser. The two main issues that stop people using it are: 1) Time: Taking a trip involving public transport is slower than a car. This is fixable in urban areas with some dedicated paths, modal filters, and very frequent schedules and that kind of thing but this takes up front resources. 2) Safety: It's not safe. Too much antisocial behaviour on public transport. Nobody wants to sit near loud or smelly people. In the worst case people get assaulted. Cyclists are more likely to get seriously hurt in a crash or have their vehicle stolen than cars. It's fixable but policing takes effort. 3) The demand paradox: "See public transport and bikes are unpopular" say the decision makers and don't put in the resources. The thing is the infra needs to be near 100% built for people to want to use it. It's no good if your cycle commute is 80% dedicated bike paths but 20% of it is riding next to trucks and parked cars opening their doors as most people would rather take a car. It's also no good if the trains run every 30mins, so on average your trip is 15min delayed. The politician would think "why would I double it if the trains are already under-utilised" but does not understand latent demand.
- aqme28 3mo ago
  You're completely wrong on safety. Driving is much much more dangerous than trains by orders of magnitude. I know what you're getting at when you write safety, but I want to be clear that this is not the same thing as safety.
  - brikym 3mo ago
    Perceived safety is exactly what I meant. It's a marketing problem.
  - sndgndgndgndy 3mo ago
    Assertions made without evidence can be disregarded without evidence, and your assertion does not match my personal experience. Public transit is dangerous, especially in cities like SF or Seattle.
    - aqme28 3mo ago
spacemanspiffii 3mo ago
I would add to the top of that list - reducing the distance people travel. Less kilometers would be very effective. Don't spend hours a day in your car. If people wouldn't be traveling so much, especially for work, this whole problem would disappear.
- bluGill 3mo ago
  The whole point of a city is all the destinations you can teach. Less km means you can go less places. No density isn't an answer, because some destinations are not dense, and even if they are we can cram more places in.
  - mcbobgorge 3mo ago
    Air travel is the best way to go long distances, but some small islands are not easily accessible by plane. For those places, we have ferries. In a similar vein, most places in a city can be accessed via density + transit. But cars are great for those non-dense destinations you describe, like wilderness areas or farms or whatever else.
    - bluGill 3mo ago
      There is a large gap between distances where flying makes S and and what you can walk. Even with an ebike the distance you can reach in a reasonable time is vastly less that a car for most trips.
simondotau 3mo ago
People will generally choose whichever mode of transport is most convenient and cost-effective, based on how they rationally (or irrationally) weigh various factors. If every road were free of traffic, every destination had unlimited parking at the door, everyone already owned a car, and driving carried no direct or indirect costs, almost everyone would drive everywhere. The only way to shift people onto public transport is to make it more attractive than driving. That can be done by making driving less convenient or more expensive—through higher ownership, fuel, and parking costs, and by resisting attempts to eliminate congestion. And by making public transport better through greater frequency, reliability, coverage, and convenience.
- simondotau 3mo ago
  After writing that post, I started drafting an edit to acknowledge that clever marketing is another way to encourage greater use of public transport. In my mind I imagined a campaign highlighting the time people get back not having to drive through heavy traffic. The advertisement could say, "Give yourself more time to do the things you love," accompanied by a wholesome image of a smiling person reading a book on the train. Then it occurred to me that nobody would actually be reading a book. They would be doom-scrolling Instagram or watching wingnut political propaganda on YouTube. I'm starting to wonder if people might be mentally better off behind the wheel...
  - pibaker 3mo ago
    Shortwave radio had a reputation for hosting political nut jobs before the internet existed. So are podcasts. At least transit users don't get road rage.
  - nicbou 3mo ago
    That's the reason I prefer public transit. I normally bike everywhere, because I get to exercise, see the scenery and yell at people, but sometimes I like to just sit down and read a book. Another benefit is being able to have a drink or go to multiple locations without worrying about bringing the car back somehow.
  - 3mo ago
elil17 3mo ago
Well, you can actually do both. This costs no money to cities and can be rolled out without any political barriers. It will have a small effect. Public and active transit costs money and requires political buy-in. It will have a large effect but takes time.
quantumwannabe 3mo ago
If you believe that adding lanes doesn't reduce congestion, then you must also believe that adding transit doesn't reduce congestion.
- jahnu 3mo ago
  Induced demand is a real, observed phenomenon for both roads and public transport. However, because of density differences, it is generally easier to increase service frequency for public transport than to add lanes for low-density road traffic. Empirically, this pattern is observed repeatedly.
- wolrah 3mo ago
  > If you believe that adding lanes doesn't reduce congestion, then you must also believe that adding transit doesn't reduce congestion. The problem with road congestion is the number of personal vehicles inefficiently carrying 1-2 people while taking up a lot of space on the road. In any situation where the roads would be clogged with personal vehicles an effective transit network will be carrying dozens or even hundreds of people per vehicle in vehicles that may not even be sharing the same lanes and thus can't contribute to road congestion.
- trymas 3mo ago
  1. Like others said - induced demand. You add one highway lane - more people will jump into cars to use it. You add tram/metro line instead - same people would like to use that instead of sitting in traffic jam, taking away traffic from the highway. 2. Continuing from first point - see linked graph in parent comment. Light rail has an order of magnitude capacity per lane compared to cars. For 20 lane highway you'll need 2 lines of light rail or 1 lane of "heavy rail" (as per graph). Insane difference! 3. There's a reason "one more lane" is a meme: https://knowyourmeme.com/memes/one-more-lane-bro-one-more-lane-will-fix-it https://knowyourmeme.com/memes/one-more-lane-bro-one-more-la...
- FuriouslyAdrift 3mo ago
  In many instances removing or repurposing lanes (road diet) decreases congestion much more effectively than just adding capacity. Congestion occurs naturally regardless of capacity due to fluctuations in flow (jitter) more often than being over capacity (this is civil engineering 101). By repurposing lanes for dedicated turn lanes, bus lanes, bike lanes, and/or pedestrian walkways, you remove many of the triggers for jitter. Synchronizing traffic (connected autodrive?) would do much more for removing congestion than just adding high over head capacity. https://highways.dot.gov/safety/other/road-diets/road-diet-case-studies https://highways.dot.gov/safety/other/road-diets/road-diet-c...
deleted 3mo ago
[deleted]

by trymas 3mo ago

ChadNauseam 3mo ago

We definitely need more metro, trams, bus routes, and bike paths. I especially want the latter because I bike to and from work every day. However, I have to wonder about the cost of these projects. In SF, we recently spent $346 million on the Van Ness Improvement Project, which added 2 miles of bus lanes. I just can't see how that's a good use of funds. If someone gave me $346 million and told me to improve society, I could think of many better options than adding two miles of bus lane. So a prerequisite to the whole idea seems to involve solving whatever is making these projects so expensive.

fragmede 3mo ago
Okay, how would you spend $346 million?
- ChadNauseam 3mo ago
  If we had to stick to transportation-specific improvements, I would use the money to eliminate bus fare for a year. (muni generates about $100M in fare, so really it would be enough money to eliminate fare for ~3 years.) Unlike subway fare, bus fare doesn't prevent n'er-do-wells from getting on the bus (they just ignore the fare and get on anyway), and it probably increases ridership and gets some people out of their cars, which reduces congestion (public benefit and therefore deserving of government subsidy).
  - bluGill 3mo ago
    Why not use the money to make bus service better? There is no city that can't effectively use many more buses. Bus riders all put service as their biggest problem over the cost.
    - ChadNauseam 3mo ago
      Improving service is much better, but the relative scales here are crazy. She options are "completely eliminate cost" or "slightly improve service in one two-mile stretch". Granted, 10 million trips a year go through that two-mile stretch that was improved, but that's just a small fraction of all bus trips in SF.
      - bluGill 3mo ago
        It is more than that, but even still we should as that would help the people who ride their routes. In almost all cases this would bring in more riders who find the new service good enough that they can stop driving.
- taneq 3mo ago
  Where I live, I’d spend it on increasing parking availability at train stations, and/or run a lot more local buses that do a small (few kilometres) circuit around the station and ferry passengers to/from the station. Taking a bus to the station currently adds an unreasonable amount of time to the journey. It doesn’t matter how good trains are if I don’t live near a station and I can’t get there.
trymas 3mo ago
One of the problems indeed. Though IMHO it's just lack of political will. Highways are built at (relative) ease, no matter the cost. Data centers are infamously now being built at society expense (electricity and water capacity), sometimes literally in peoples backyards. At the moment I don't have the receipts, but from anecdotes - it's all just political will. There's a highway extension? Some properties are taken by eminent domain, some other NIMBYs are told to just suck it up. Data center? Forget about it - foundations are being laid this moment (sometimes no matter the law)! High speed rail? We must listen to every NIMBY on the proposed path, hence it will take 200 years to listen to all complaints and align opinions of the people impacted. Millions speant on "research, enviornmental impact and public opinion" - project stalls and is closed after 5 years. NB: I am not from USA, I think this pattern fits many (especially western) countries. Successful projects (I repeat myself) are always based on political will, when rule/law framework is designed to make such projects easier and much cheaper. NB2: Also as with anything - when you start building you get experience and expertese - the more you build the cheaper it gets. A lot of places havent built new train/metro/tram line in decades - hence all expertese must be built from scratch (from policies, to government clerks knowing how to deal with such projects, to construction businesses who never built rail in 50 years, etc.).
- Tade0 3mo ago
  > Highways are built at (relative) ease, no matter the cost. It's like that because it's a misconception that highways are built for passenger cars. They're built for freight and all kinds of business activities - regular people using them are just a bonus. The majority of petroleum-based fuel, wear and tear on the highways and toll revenue comes from everything but passenger cars on highways.
  - jcranmer 3mo ago
    Almost all of the new highway construction is for passenger cars. Yes, the interstate highways were built in part to facilitate intercity truck traffic, but the reason for building yet another beltway around, say, Houston isn't for trucks but for all of the passenger cars in the region that are congesting the roads.
gsliepen 3mo ago
> However, I have to wonder about the cost of these projects. A very good way to deal with this is to recognize that all infrastructure needs maintenance and periodic replacement. Once it is time to replace a road, that is when you change it to include bike paths, bus lanes and so on. You need some foresight, planning, make new road designs part of law, and political will. Some countries have made this work very well.
inigyou 3mo ago
This feels like an instance of America being unable to build things due to corruption. Two miles of any lane shouldn't cost over a hundred million dollars per mile. Repainting a lane should be vastly less and even if they're building a new flyover just for buses it shouldn't cost that much. Something is happening there. It is not getting built in an effective way.
- queenkjuul 3mo ago
  Can almost guarantee that project involved much more that just bus lanes. I don't believe even California can spend that much on paint. (And it did, the entire roadway, sewer, and water mains were replaced, traffic signals were replaced, etc: https://www.sfcta.org/projects/van-ness-improvement-project https://www.sfcta.org/projects/van-ness-improvement-project)
Cthulhu_ 3mo ago
The challenge that "developed" countries / cities have is that there's already a lot of existing (and aging) infrastructure around. Meanwhile in other countries they build new cities from scratch, including infrastructure based on current-day knowledge of how these things pan out long term. I think the US has the space and funds to do so. If they were to build a new city from scratch for the next 250 years, what would it look like?

wwind123 3mo ago

Also...allow people to work from home more. During the Covid pandemic, most white-collar employees work from home, and the commute and the traffic is usually not a big problem. But now more and more companies ask employees to go back to office, and traffic jam is becoming a headache again.

rob74 3mo ago
Yup... hours of commuting time just to sit in Zoom/Teams/Slack/whatever calls while in the office instead of at home makes no sense at all, and is bad for the environment (even if you use public transportation, not going to the office still emits less CO2 than going there). But because RTO is just a way of trying to get rid of employees without severance costs, these and other points will invariably fall on deaf ears...
gampleman 3mo ago
I wonder if a very small tax for RTO (perhaps with exemptions for manual jobs) would do the trick? I think it would help with making companies handle that externality.
- Ntrails 3mo ago
  > I think it would help with making companies handle that externality. This is backwards, companies do not choose where employees live. Employees do. That they choose to live with long and unpleasant commutes (typically in exchange for more space, cheaper housing etc) is in general terms on them not the company. I'll allow that the rowback of wfh from a previously fully remote job is on the company - but certainly outside of that I have little agreement.
  - inigyou 3mo ago
    Companies as a collective also choose the geographical distributions of offices and housing and the price of each.
  - Cthulhu_ 3mo ago
    While true, there's (often, not always) an inverse correlation between location of work and cost of living. Few people can afford to live close to the office. What would work (at least in my country, and in my head / from my armchair) is sattelite offices. I live in a neat suburb with an industrial estate with some office buildings, if my job opened a sattelite office there I would be much more inclined to go to the office. But then, they would need to make sure that only people that live nearby go to that office. Given that a lot of teams are multidisciplinary, that would be difficult. Plus, the job would need to offer long-term stability, and only few jobs in software can promise stability for more than a year. If they want people to move close to work, it has to be both affordable and guaranteed stable for at least 5-10 years. I looked into it once, there was an office for a software company across the street and I applied there. But the two offers they made were both lower than what I was earning at the time, to the point where I wouldn't be able to live there. And second, after the pandemic they closed the office and became a remote-first company.

rob74 3mo ago

Yes - when I read "both navigation users and non-users share the advantages of decongesting targeted segments", I wondered how long these advantages would last. It's widely accepted that less congestion will encourage people to travel by car more, which will soon eat up the gains (https://en.wikipedia.org/wiki/Induced_demand#Definitions https://en.wikipedia.org/wiki/Induced_demand#Definitions)

AnthonyMouse 3mo ago
> It's widely accepted that less congestion will encourage people to travel by car more, which will soon eat up the gains This is not only not widely accepted but extremely misleading. The nature of "induced demand" is really that congestion suppresses demand. Which behaves in an entirely different way than the name implies. If demand was being induced then all attempts to relieve congestion would be permanently impossible, which is nonsense. There are empirically places with less traffic congestion. Whereas if demand is being suppressed then an apparent capacity shortfall in the amount of 0.5X may really be a shortfall of X. Adding 0.5X then doesn't work, because congestion will remain until you add X, with the suppressed demand filling back in to the extent that you satisfy it. In order to relieve the congestion you have to add enough capacity to satisfy the demand that would exist in the absence of congestion, which is more than the amount that exists now, but not an infinite amount that unconditionally consumes all possible capacity or efficiency increases.
- inigyou 3mo ago
  There's a related paradox - I don't remember the name - that the speed of traffic is determined by the speed of public transit. Cities with less car congestion probably have faster public transit.
  - AnthonyMouse 3mo ago
    That doesn't seem like a paradox at all. If you have more convenient public transit then more people use it. If more people use it then there is less traffic. This is also why things like bus lanes are ridiculous. The theory is supposed to be that making the bus faster than cars will get more people to use it. But if that actually created a benefit that exceeds its cost, i.e. got more people to take the bus than the wasted capacity of not allowing cars to use that lane when a bus isn't, then it would reduce the traffic congestion that it inherently requires. It's a thing that can't even be part of the solution to the problem because any means of actually solving the problem would eliminate its mechanism of operation.

AnthonyMouse 3mo ago

> here's a good graph The trouble with this graph is that it assumes the buses/trains are full. It obviously doesn't apply to a bus with one passenger on it, which takes up even more space than a car. From which we can observe the problem. Alice is at home and wants to go to work. She travels along a low density street for a few miles, enters a congested thoroughfare for a few more miles, then travels along another low density street to her destination. She can't take a bus at the endpoints because she would be the only one on it, but if she took a bus only on the congested thoroughfare then she'd end up on the far side of it without a vehicle to get the rest of the way to her destination. To fix this the thing you need before mass transit (by several years) is zoning rules that allow higher density construction in a higher percentage of the land area where people live and work.

aqme28 3mo ago
I believe this is based on actual average usage, not by assuming the vehicles are full.
- AnthonyMouse 3mo ago
  Which would be even worse, since existing mass transit is naturally concentrated in the places where it can operate with high capacity, and it thereby has a higher existing average than passenger cars. Lots of mostly full commuter trains, not a lot of 8-passenger SUVs that actually have 8 passengers. When the the proposal is to add more mass transit, it would then have to go in the places it currently isn't, i.e. the places where it would have to operate at lower capacity. Which leads to the problem described.
trymas 3mo ago
> The trouble with this graph is that it assumes the buses/trains are full. It obviously doesn't apply to a bus with one passenger on it, which takes up even more space than a car. IMHO it's a bit moot to delve into extremes. Average car occupancy is around 1.5 passengers. I'd bet that such number is far from average for average bus/train/tram/metro. I also probably won't make a mistake stating that "Average car" in USA is either a very big SUV or even bigger "truck" (which probably has a footprint as half of a bus). You also need to park your car somewhere at the destination. I also thought that there will be reply like yours, though you answered your own problem: > To fix this the thing you need before mass transit (by several years) is zoning rules that allow higher density construction in a higher percentage of the land area where people live and work. Of course you don't want to build trams and all in low density (and low population) areas and my comment didn't apply for such case. You must have density as well as mixed use zones. I am not from USA and seemingly prevalent single use zoning[1] is very foreign to me. It all comes down to efficient urbant planning. [1] correct me if I am wrong on this.

brikym 3mo ago

I think most people get that non-car forms of transport is denser. The two main issues that stop people using it are: 1) Time: Taking a trip involving public transport is slower than a car. This is fixable in urban areas with some dedicated paths, modal filters, and very frequent schedules and that kind of thing but this takes up front resources. 2) Safety: It's not safe. Too much antisocial behaviour on public transport. Nobody wants to sit near loud or smelly people. In the worst case people get assaulted. Cyclists are more likely to get seriously hurt in a crash or have their vehicle stolen than cars. It's fixable but policing takes effort. 3) The demand paradox: "See public transport and bikes are unpopular" say the decision makers and don't put in the resources. The thing is the infra needs to be near 100% built for people to want to use it. It's no good if your cycle commute is 80% dedicated bike paths but 20% of it is riding next to trucks and parked cars opening their doors as most people would rather take a car. It's also no good if the trains run every 30mins, so on average your trip is 15min delayed. The politician would think "why would I double it if the trains are already under-utilised" but does not understand latent demand.

aqme28 3mo ago
You're completely wrong on safety. Driving is much much more dangerous than trains by orders of magnitude. I know what you're getting at when you write safety, but I want to be clear that this is not the same thing as safety.
- brikym 3mo ago
  Perceived safety is exactly what I meant. It's a marketing problem.
- sndgndgndgndy 3mo ago
  Assertions made without evidence can be disregarded without evidence, and your assertion does not match my personal experience. Public transit is dangerous, especially in cities like SF or Seattle.
  - aqme28 3mo ago

spacemanspiffii 3mo ago

I would add to the top of that list - reducing the distance people travel. Less kilometers would be very effective. Don't spend hours a day in your car. If people wouldn't be traveling so much, especially for work, this whole problem would disappear.

bluGill 3mo ago
The whole point of a city is all the destinations you can teach. Less km means you can go less places. No density isn't an answer, because some destinations are not dense, and even if they are we can cram more places in.
- mcbobgorge 3mo ago
  Air travel is the best way to go long distances, but some small islands are not easily accessible by plane. For those places, we have ferries. In a similar vein, most places in a city can be accessed via density + transit. But cars are great for those non-dense destinations you describe, like wilderness areas or farms or whatever else.
  - bluGill 3mo ago
    There is a large gap between distances where flying makes S and and what you can walk. Even with an ebike the distance you can reach in a reasonable time is vastly less that a car for most trips.

simondotau 3mo ago

People will generally choose whichever mode of transport is most convenient and cost-effective, based on how they rationally (or irrationally) weigh various factors. If every road were free of traffic, every destination had unlimited parking at the door, everyone already owned a car, and driving carried no direct or indirect costs, almost everyone would drive everywhere. The only way to shift people onto public transport is to make it more attractive than driving. That can be done by making driving less convenient or more expensive—through higher ownership, fuel, and parking costs, and by resisting attempts to eliminate congestion. And by making public transport better through greater frequency, reliability, coverage, and convenience.

simondotau 3mo ago
After writing that post, I started drafting an edit to acknowledge that clever marketing is another way to encourage greater use of public transport. In my mind I imagined a campaign highlighting the time people get back not having to drive through heavy traffic. The advertisement could say, "Give yourself more time to do the things you love," accompanied by a wholesome image of a smiling person reading a book on the train. Then it occurred to me that nobody would actually be reading a book. They would be doom-scrolling Instagram or watching wingnut political propaganda on YouTube. I'm starting to wonder if people might be mentally better off behind the wheel...
- pibaker 3mo ago
  Shortwave radio had a reputation for hosting political nut jobs before the internet existed. So are podcasts. At least transit users don't get road rage.
- nicbou 3mo ago
  That's the reason I prefer public transit. I normally bike everywhere, because I get to exercise, see the scenery and yell at people, but sometimes I like to just sit down and read a book. Another benefit is being able to have a drink or go to multiple locations without worrying about bringing the car back somehow.
- 3mo ago

elil17 3mo ago

Well, you can actually do both. This costs no money to cities and can be rolled out without any political barriers. It will have a small effect. Public and active transit costs money and requires political buy-in. It will have a large effect but takes time.

quantumwannabe 3mo ago

If you believe that adding lanes doesn't reduce congestion, then you must also believe that adding transit doesn't reduce congestion.

jahnu 3mo ago
Induced demand is a real, observed phenomenon for both roads and public transport. However, because of density differences, it is generally easier to increase service frequency for public transport than to add lanes for low-density road traffic. Empirically, this pattern is observed repeatedly.
wolrah 3mo ago
> If you believe that adding lanes doesn't reduce congestion, then you must also believe that adding transit doesn't reduce congestion. The problem with road congestion is the number of personal vehicles inefficiently carrying 1-2 people while taking up a lot of space on the road. In any situation where the roads would be clogged with personal vehicles an effective transit network will be carrying dozens or even hundreds of people per vehicle in vehicles that may not even be sharing the same lanes and thus can't contribute to road congestion.
trymas 3mo ago
1. Like others said - induced demand. You add one highway lane - more people will jump into cars to use it. You add tram/metro line instead - same people would like to use that instead of sitting in traffic jam, taking away traffic from the highway. 2. Continuing from first point - see linked graph in parent comment. Light rail has an order of magnitude capacity per lane compared to cars. For 20 lane highway you'll need 2 lines of light rail or 1 lane of "heavy rail" (as per graph). Insane difference! 3. There's a reason "one more lane" is a meme: https://knowyourmeme.com/memes/one-more-lane-bro-one-more-lane-will-fix-it https://knowyourmeme.com/memes/one-more-lane-bro-one-more-la...
FuriouslyAdrift 3mo ago
In many instances removing or repurposing lanes (road diet) decreases congestion much more effectively than just adding capacity. Congestion occurs naturally regardless of capacity due to fluctuations in flow (jitter) more often than being over capacity (this is civil engineering 101). By repurposing lanes for dedicated turn lanes, bus lanes, bike lanes, and/or pedestrian walkways, you remove many of the triggers for jitter. Synchronizing traffic (connected autodrive?) would do much more for removing congestion than just adding high over head capacity. https://highways.dot.gov/safety/other/road-diets/road-diet-case-studies https://highways.dot.gov/safety/other/road-diets/road-diet-c...

deleted 3mo ago

[deleted]