I recently watched a video about autonomous car and the dude argue the tech isn't here yet, but it will work if we build a lane just for autonomous car and put every autonomous car on that lane.
Everyone in the comment basically calling him out for reinventing the train lol.
He seemed to casually ignore that at the end of the tunnel was still the concept of an offramp with a 25mph street that everyone was funneling to.
Of course he never planned on building it anyway. It was all just to distract from California High Speed Rail, because that directly gets in his way of selling more cars.
because that directly gets in his way of selling more cars.
Which is stupid in itself, because the entire goal of the CA HSR project is to link long distance corridors, not putzing around town like most do with a Tesla.
Just to be pedantic, the dumb car tunnels (or Loop), are the weird thing elon "invented" to "solve" traffic and reduce competition for his cars for urban transport. This eventually became one tunnel in LA to get between elon's house and office, and the dumb taxi tunnel in Las Vegas.
The hyperloop, where elon "invented" the vacuum train, is a separate thing that exists to distract from CAHSR, and elon didn't want to work on himself because "he's too busy", and not because it's effectively just a scam and won't work, and most of the companies that started up to develop it have since gone bust.
I once heard of an experiment in economics that offers insight into this.
Say you have 100 people. You give each of them one of two choices:
A : you get $40 unconditionally
B: you get $70 - n, where n is the number of people who choose B
You end up getting, on average across experiments, n = 30.
If you move the numbers around (i.e, the $40 and the $70), you keep getting, on average, a number of people choosing B so that B pays out the same as A.
I think the interpretation is that people can be categorized by the amount of risk they’re willing to take. If you make B less risky, you’ll get a new category of people. If you make it more risky, you’ll lose categories.
Applied to traffic, opening up a new lane brings in new categories of people who are willing to risk the traffic.
Or something. Sorry I don’t remember it better and am too lazy to look it up. Pretty pretty cool though.
I heard a city planner talk about why adding a new lane doesn't help, and the term they use is "induced demand."
Basically, people are going to take the route that they consider the most convenient, and that usually comes down to time and effort. Traffic hurts both by taking more time and being more stressful to deal with. When you add a new lane to a road, people think that the traffic will be easier there, so they take that route instead of their normal one. So you're just adding more cars to the traffic that match or exceed the throughput of your new lane, basically putting you back at square one but a few billion dollars more poor.
You've essentially added a single lane one-way road to help ease traffic across the entire city.
As a road widening project is completed, traffic is alleviated for a short amount of time. Then as time passes word spreads, or more people move to the city, or kids get older and get their driver's licences. More and more people know this widened road is the fastest route, so more people take it, thus undoing the improvement. Then the cycle starts again - either with the same road being widened again, or another one a block over, on and on until the world is covered in asphalt.
The solution is to make alternative transit more appealing than cars. Bikes and public transit already have significant financial benefits, but lack infrastructure to make it more viable in North America. Busses get stuck in traffic, bikes are forced to share lane space with cars or sidewalks with pedestrians.
How is alternative transit the solution? Cities that have public transportation still have traffic jams.
There was an English traffic engineer that predicted that avg speed in central London will always be like 9mph. No matter how many lanes or public transit options you add. If there is no traffic, people will take cars until traffic jams are unbearable to give up. Then the system finds equilibrium.
Yes. That wasn’t the best word choice; maybe “group” would have been better. I meant groups of people who are willing to take some level of risk. Imagine the categories are “low risk takers”, “medium risk takers”, and “high risk takers”.
Compared to A paying out $40, if you make B $50-n you’ll only get the high risk takers choosing B. If you make it $70-n you’ll get high and medium risk takers. If you make it $120-n you’ll get almost everybody.
If risk taking is a value between 0 and 1, the categories are groups of people inside certain intervals. For example, low could be [0, 1/3), medium could be [1/3, 2/3), and high could be [2/3, 1].
I don't really like including pedestrians in there. Like sure, you can fit a bunch of people in a small area, but another point you shouldn't ignore is the throughput over time, and pedestrians are by their nature rather slow. Obviously if you're looking at shopping in a street lined by shops left and right, then that street becomes tailor-made for pedestrian traffic (and nothing else except perhaps bicycles). But public transport is much better suited for travelling any further distances, and that should be the main focus when deciding to ditch cars.
Sure! Both speed and distance matters a lot for throughput. The advantage of pedestrian traffic is that designing for it reduces the distance people have to travel and that it combines very well in conjunction with public transport, unlike cars. Also, the speed of mixed traffic is inverse correlated to the number of vehicles, hence is a special case in this regard where throughput may decrease as the volume per lane increases. The overall point however is that a single train can substitute a staggering amount of private vehicles (and who doesn't love leaning back, listening to music and reading the news while commuting?).
The units are passengers per hour. If they didn't account for speed, pedestrians would theoretically be one of the highest, since you can pack people together fairly tightly and still have them walk.
Well, no one is saying cars are worse for all purposes. If you want to take your family and dogs to a cabin in the mountains while also shopping for food along the way, it is probably going to be your best bet. Still, that is not what is pictured in the post. These are commuters that are probably moving from work to home (or vice versa), where cars really are the worst of most options. If the bus takes longer, it is probably an issue of allocation of funds for a shorter route and exclusive lanes for it.
My town does buses better than that, but peak hour buses get stuck in traffic
So times when it's a 20 minute drive, it's 30 or 40 minutes by bus, when the same drive is 45 minutes in slow traffic, the bus is not a lot worse, at 1 hr
Anyway the better solution has busses only as a last mile solution, with trunks covered by rail
Think of it like trickle down economics. If it hasn’t worked yet, you just need to make sure that the fat cats on top are fed so forcefully and so fast that something starts trickling down eventually.
Um acttschually, we knew about induced demand as early as 1920, but the government just doesn't care about science. (It used to be called traffic generation)
Part of it is that the organisations that design and build roads are also the ones who assess whether a road is needed. No big surprise that they "forget" about induced demand
The other point to make here is, obviously you look at this highway trip and say “Well I am obviously not walking or biking it.” But, the expansive gaps between home and destination are often caused by many many roads and parking lots like this one. We have dedicated gigantic land masses specifically to cars, and it actually lengthens travel time to our destinations.
I have been to countries where, even if thin highways exist, they’re not the rule and it’s easy for other modes to get under or around them; and their roads don’t dominate the urban areas. There, the answer is simple: Just walk, you don’t even need a bike.
The approach worked as intended, more perfectly even.
Look at all those useless expenses on the pic, some people profited on products that weren't necessary to begin with, and put a lot of moneys in so the system wouldn't accidentally change for the better.
Buses and trains. That, or spaghetti interchange that are bigger than the rest of the city. Also, replace key arterial roads with a pedestrian path, call that path a park, and charge $20 for entry. That will easily fund all the city services and nobody will be too inconvenienced by having to pocket their car as they walk across the "park" to get between neighborhoods. Now excuse me, I have to go murder a little blue bird that won't shut up about the garbage piling up
In a place with essentially nothing but narrow two lane roads, no bike lanes or sidewalks, a little wider might serve some good. Adding a turn lane and a bike lane would free up tons of traffic.
If the highway increases in size, then more off ramps or more lanes in the off ramps are needed, which in turn need more lanes on the main street that connect to the off ramps. It's basic filtration system dynamics.
I'm not talking about highways, I'm taking about roads connecting suburbs etc. The only way I can get to work. They're terrible and only accessible to cars.
My town wants to widen a section of road near me. It's the only part of the road with only one lane each way
I'm torn. I know widening the road won't help traffic (right now that narrow bit reduces through traffic, making it a nice bit of road to drive) but if they do widen it, they will also add cycle lanes.
So many people commuting to jobs that could easily be done from home nowadays
I work in the freight industry in a position I can't do from home but when the whole work from home thing was in full swing I didn't get stuck in traffic except a few times when the local drawbridge went up
This is the most infuriating part. The best solution to these issues is to remove the need to move in the first place, and WFH for the people that want it and who can do it removes a huge amount of traffic with comparably little cost (company laptop, a screen and maybe a desk and chair, many of which could just be taken from the office).
I keep thinking this during my daily commute along a 3 lane freeway.
If a bus/truck overtakes another bus/truck (often), it basically becomes a single lane freeway.
And during peak, that little manoeuvre is going to cost you and hundreds of cars behind you, probably for a long time.
My small city's main suburb to centre link is a 100km/h, two lane each way parkway, until it merges with a similar road from a different centre, grows to 3 lanes each way, and slows down sharply as it gets close to the centre
Between the last traffic lights and the spaghetti junction that merges it with a similar road it's free flowing and fine. The slow lane goes about 95, the fast lane about 100 to 110, with occasional slight slowdowns when a 95km/h car catches up with a slower one
But on that stretch there's about 300 metres of slow traffic due to a fixed speed camera. People going 95 who think their speedometer might be wrong the opposite way to which it is slow to 80; people doing 110 slow to well below 100, people following too close brake heavily, the fast lane ends up with a standing wave with a peak (or is it a trough?) of 60km/h
Then as you get past the camera it gets loud with even the slow cars rebelling against the slowdown give much throttle. That camera must cost so much CO2. I doubt it catches anyone except during the lightest traffic times. In even medium traffic you couldn't speed through that bit of road if you tried
I promise you the number of people living in that city in 1970 is considerably fewer than the number of people there now. Of course you need to continue expanding infrastructure.
I wonder if a picture like this could be used to fool future archeologists (or paleontologists or historic internetologists, or whichever would be studying it) into thinking we put great effort into segregating people with white lights and scum with red lights from using the same roads.
Seattle, Washington is a pretty big place. Right? There are more people in Los Angeles county than all of Washington State. It's absolutely insane the number of people who move from affordable areas around L.A. into the city and back every day.
People will talk about induced demand and all that. But those people really just want to be able to get around. The fact that they just don't because the traffic is so bad doesn't mean you shouldn't add more lanes. It means you should add a lot more. Same with the one lane at a time approach. The fact that it didn't work does mean you are doing something wrong, but it maybe that you need to add 5 lanes at a time, not one.
Now I'm not saying they should actually do that, just that the arguments against are BS.
A comprehensive public transit system, well maintained and well patrolled is what LA really needs. I am talking Paris metro on steroids. And it is going to cost in the trillions. But it isn't getting any cheaper by waiting.
Adding, say, a sixth lane doesn't increase capacity as much as adding a 2nd lane, because traffic jams are generally because of interactions. It's very rarely the straight road that has a capacity problem. Adding a sixth lane adds capacity, but also creates more interactions.
Also, car lanes have a shit capacity, which goes down massively when it's busy. Like you said, mass transit is vastly superior, but even a dedicated bus lane would help. In contested traffic, a car lane transports less than a single bus per hour.
Yeah, the interactions suck. But if dealt with earlier, they could have been mitigated. Same way mass transit does. Express trains. Have a highway over a highway that goes to a specific place. If you stack enough of those, people get on the one they need and go straight to where they need to get. Not realistic though unless planned in advance.
That's the whole thing about induced demand though: People want to get somewhere and believe it or not, not everyone does so by car. But if you decide to add more lanes it temporarily improves traffic leading to those people that didn't take a car in the past or lived somewhere else because they knew traffic would be horrible if they moved, to actually commute by car now / go forth with their plan to move, increasing the amount of traffic again until it's as bad if not even worse than before.
Cars don't scale. Cars aren't for mass transport and shouldnt be used for that. A city with a highway like in the picture really needs a transit system/a better one and fever lanes
See you are missing the point. The demand isn't induced, it was always there. They wanted to move and use thier car, but traffic was too bad. My complaint is with the BS argument that the extra lane caused demand to materialize out of no where. It was always there, just unserved.
Beyond the fact that adding five more lanes would still leave you with a horribly inefficient transport system, you also ignore that externalities that you are exacerbating by doing so. You're displacing thousands more people, worsening the division of communities, creating a lot of noise and air pollution, increasing car dependency etc
I always feel like these induced demand arguments are suggesting that adding more lanes means the same number of people are just choosing to do more driving. Maybe, as you add more lanes you create the infrastructure for a city to grow, and it adds more people which then fill up the new lanes. People aren't just going out and buying a new car or rolling an existing car out of the driveway that they were previously not using because a new lane is built. These are net new drivers, who would not be in that city if the infrastructure for them hadn't been built.
Exactly, thank you. If you build a 6-lane highway in Montana it's not going to magically fill up with traffic, thus one can conclude that context is missing from the Reddit-tier explanation of induced demand or that the entire idea of induced demand is wrong.
Induced demand actually means that more people drive now because the people that didn't drive in the past / lived somewhere else because it was less convenient because of the traffic to commute by car or live somewhere else where they would have needed a car now decide to commute by car / actually move (yeah that also something we have observed) because the widening temporarily improved traffic. In the end traffic ends up the same if not worse.
Induced demand isn't something the Internet has come up with. It's actually a real thing that has been studied and researched. We know it exists.
It functions on the basic principle of: If you improve something and make it more convenient to use that something, more people will actually use it.
The problem isn't where the traffic is, it's where the traffic isn't.
Say you've got 3 lanes into a set of traffic lights and 90% of the traffic continues into 1 lane, then you can add however many lanes you want to the ingress road, but it's still going to fill up and have the same throughput as the bottleneck is the egress.
That said, it can be people doing bad merges, etc. but that's going to happen regardless of how many lanes you put in.
People on here love to shit on Houston's massive expansion of I-10 as a failure.
It worked great for years, but the population continued to grow. Having 5 fewer lanes on each side would just make things worse or increase sprawl by pushing people further out to thin the traffic. They ain't gonna mass-adopt bicycles in a city where the heat index is 115° + for months at a time
But that's the thing about induced demand. Of course widening a road temporarily improves traffic. But only temporary. That temporary improved leads to more people deciding to drive a car when they didn't in the past or even having different moving options in mind now which they didn't because if traffic. In the end traffic ends up the same if not worse than before.
That's not something the Internet came up with. It's been studied and researched for years.
It works on the simple principle of: If you make something more convenient to use, more people will use it.
Cars just don't scale. They can't do mass transport and aren't meant for that.
You need to make a city walkable and have a proper public transport system otherwise you will only ever lose even more money on car infrastructure while continuing to worsen traffic, heating up the city because of the sealed surfaces, making the city less desirable to actually exist in and worsening it's economy.
Build the city properly and people will actually choose a different option. No matter the climate in that city. Especially because heat is only worse with massive amounts of car infrastructure because they usually result in less green spaces and trees which provide shade and a cooling effect in the city.
Not forcing everyone to go to a big centralized city rather than spreading everything out will actually fix it. We started doing that long ago but recently have started listening to greedy real estate developers gentrifying cities and now EVERYONE GO TO CITY TO DO THING and people are now shocked, SHOCKED that traffic into and out of cities is out of control.
And love how other "solutions" are LOL MASS TRANSIT. Yep, going somewhere on a track that doesn't go immediately to a certain place then having to get on a damn bus or in a taxi or a freaking Uber scam to actually get where they need to go which is not only ableist because it's difficult for people with mobility issues to do that, but also problematic if you need to actually transport any decent amout/size of goods on said public transportation. Cars are the best at getting places and no amount of whining and bitching and complaining is going to change it.
Could the problem be that all the money went into building roads and car centric cities, and no money was spent on making mass transit better or rethink on how urban sprawl might cause massive traffic problems?