What happens if you turn off the traffic lights? | Hacker News Reader

What happens if you turn off the traffic lights?

theguardian.com

112 pointsokket91 comments

I was in Miami after Hurricane Andrew. The traffic lights didn’t return for weeks. It was rather amazing.

For less busy intersections, people just treated them as 4 way stops.

For busier intersections, say a 3 lane road with a 2 lane road crossing it, there was sometimes a police officer to direct traffic. But sometimes not, and that’s when it got interesting. What would often happen is that the different traffic directions would try to take turns. One direction would get momentum going until someone brave enough in the other direction would poke their car out. Eventually the one direction would stop and the other direction would start going.

But sometimes even that could not work. And this is when the volunteer traffic director would appear. Someone driving with a passenger would have their passenger get out and start directing traffic till their car got through and maybe for a couple more minutes. Then that person would go get back in their car and suddenly another volunteer would hop out of another car. Serial volunteer traffic directing is one of my enduring memories of Miami from that time.

In Florida (and every other state that I'm aware of), a dead traffic light is, by law, to be treated as an all-way stop sign, so you're supposed to take turns. Traffic lights are so incredibly reliable that many people seem unaware of this fact, though, based on what I've observed. Perhaps the behavior you describe is due to people intentionally disobeying the rules?

Things get really interesting when there are intersections of multilane highways. For example, an intersection of two 6-lane (3 each way) highways.

With 12 lanes of cars constantly approaching the intersection, that's a lot to keep track of to figure out who goes first.

I saw this recently with Irma in FL. Mostly each set of lanes would start moving roughly together once one person got brave enough to enter the intersection. But it's very hard to adjust to.

I even found myself sometimes just going after stopping without fully checking to see if I had the right-of-way or not.

There used to be a 4-way stop with 11 lanes that I would frequently drive through. It wasn't the prettiest but it worked better than I would've thought.

https://www.google.com/maps/@37.5600363,-122.2845215,3a,75y,...

In Iraklio, Greece, this is how you drive. We even have a name for it: "Taliban driving". You assume you always have the right-of-way and you go. If you don't, you will never get anywhere. Anyone says otherwise, you tell him to go woohoo himself. And then people from Crete wonder why so many people die in the road every year!

Reminds me of a joke: a guy is riding in a car with his friend when the friend zooms through a red light. The passenger exclaims: “what are you doing, you’re going to get us killed!” The driver says: “don’t worry, I learned to drive from my brother and he drives through red lights all the time.” They approach another red light and again the driver zooms through and the same conversation ensues. A few minutes later they come to a green light and the driver screeches to a halt. “Why are you stopping!? The light is green” says the passenger. The driver replies, “Yeah, my brother might be coming the other way!”

(I thought this was an early George Carlin joke but I can’t say for sure.)

"Taliban Driving"?

In New York we call it driving.

New York's not that bad :)

Traffic lights are often installed in intersections where there are too many cars for an all way stop. When there are a lot of cars approaching an intersection, a traffic light can increase throughput.

All-way stop signs are so ridiculously inefficient. It's no wonder people ignore the rules.

Law has more to do with liability than practicality. Imagine trying to settle a dispute or lawsuit involving a volunteer traffic director, for instance.

People can be incredibly cordial when there aren't any problems or one big common one they can focus their efforts around. It isn't until personal liability enters the equation that the finger-pointing gets going.

It would be nice if they could remove the stop signs for one road and just post yield signs for the intersecting road.

So two ways Stop, two ways Yield? This sounds like an accident waiting to happen and/or an invitation to gratuitous ticket-writing.

Reason being, given that this construction is expressly prohibited in many (most?) jurisdictions, there's clearly no right-of-way rule for such a combined intersection that's universally understood or taught, and I can think of several "reasonable" candidate rules that drivers would invent on-the-fly upon first approaching such an intersection.

As an aside, I'd personally assume that such a "all-way combo" intersection would essentially devolve into an all-way Stop in any case where traffic is either approaching or stopped at two or more cross directions, if only because this seems to be the rule least likely to fail catastrophically against both itself and a variety of other rules.

Does anyone know of any jurisdiction that permits this sort of intersection, and, if so, what the right-of-way rules are there?

> So two ways Stop, two ways Yield?

No, traffic one one road has the right of way and traffic on the intersecting road has to yield the right of way.

This is interesting, in Europe traffic lights are always associated with traffic signs (at least in countries I drove) and one traffic lights are off for some reason, you should obey traffic signs. If the light is on, you ignore the signs.

This way in case of issues with traffic lights or when the city is jammed and they turn off the lights, everyone knows what to do.

lights going out isn't that rare, at least where i'm living, and people know how to handle it. it's just if you have enough lanes of traffic, it's too much coordination to treat it properly like an all-way stop.

I think many people know EXACTLY how to treat a dead traffic light, it's just so uncommon that they forget.

I've seen less than a dozen times either a blinking-red or a dead light.

Blinking red is more confusing than a not-working-at-all traffic light IMHO.

>a dead traffic light is, by law, to be treated as an all-way stop sign

And if people actually did that, it would be a disaster.

I'd like to think the behavior described is due to people not being complete idiots.

My experiences scootering around in Southeast Asia wasn't much different. Traffic flow was surprisingly efficient in many quite congested uncontrolled intersections. The downside was that accidents were common.

> What would often happen is that the different traffic directions would try to take turns. One direction would get momentum going until someone brave enough in the other direction would poke their car out. Eventually the one direction would stop and the other direction would start going.

That's pretty much how roundabouts work when traffic gets heavy.

Most sane countries do not have 4-way stops. No sane and rational country has 3-out-of-4-way stops, which is the most stupid and dangerous idea ever invented. How could anyone have even thought of suggesting such a thing, let alone allowing it to happen for real - only in America!

Where I grew up the city actively avoided traffic lights (too expensive!) and opted for roundabouts wherever possible. While you would always encounter the odd tentative person who screwed things up, generally they did a wonderful job of regulating traffic flow. I contrast that with the US city I now live in where it feels like you can't drive 200 feet without grinding to halt to wait at yet another red light.

Roundabouts are great and I am 100% in favor of their use, but they are not a drop-in replacement for all traffic lights. Roundabouts are best IMO (not a traffic engineer) for medium speed intersections with one or two lanes each way, and low to medium traffic. High speeds, three or more lanes each way, and high traffic volumes and you may do better with a traffic light.

And really, again not a traffic engineer, but I wonder if we could solve a lot of these problems by simply eliminating left turns from feeder streets onto arteries (or allowing them, but refusing to put in stop lights). They mess up optimal light spacing and screw with timings. I'm not really aware of a good reason to have them aside from neighborhood residents want them.

> I wonder if we could solve a lot of these problems by simply eliminating left turns from feeder streets onto arteries (or allowing them, but refusing to put in stop lights).

I think it would be better to disallow those types of left turns entirely and direct traffic to make a U-turn at next available intersection. During busy traffic times, it's often easier to to that compared to trying to make left. Even during times it's not so busy, making a right turn with a subsequent U-turn doesn't take that much longer.

3 lanes each way in a level interaection seems like a bad design to begin with. I have never seen a 3 lane (3 lanes in each direction) road cross another at the same level. One road should go over and the other under, with large onramps for turns. Because a 3+3 road is a highway and has no place in a dense area at all.

Where I live we have this massive traffic circle thing. It has four levels - N/S, E/W, Traffic Circle, diagonal train tracks.

East/West direct road has traffic lights on either side of the thing. I find absolutely infuriating to be sitting on this marvel of efficiency waiting for an unsynced traffic signal to turn green.

Excluding the odd road works, there are no traffic lights anywhere in Marlborough, New Zealand, they use roundabouts everywhere. Driving is actually fun here.

Ha, NZ was the unnamed country in my post!

> In the behavioural analysis, cyclists at the stop line glared at the signal, almost willing it to turn green.

This is amazing. I have never seen a cyclist waiting at a red light. I think you need this kind of culture among cyclists before you can do something like taking away lights. I have never been hit by a car, but I have twice been hit by cyclists either ignoring stop lights when I had right of way, or ignoring bike lane markers and veering into pedestrian walkways. This was in Boston and NYC.

Here in Groningen (the Netherlands) I'd say 90% of people wait at a traffic light. Thing is, here cycling isn't something done by risk-takers. We have 80 year-olds cycling to the grocery store. That leads to a whole different group mentality than looking at those willing to cycle in NYC. Heck, I'd be hesitant to cycle in NYC.

Another difference (most likely) is that it's quite common for US traffic lights to switch only when they detect traffic on one of the roads, and this rarely works with bicycles.

Nothing like sitting at a red for 2 minutes before realizing you have to either run it or go on the sidewalk.

Maybe not so common on the East Coast, but 4-way stops are another can of worms here. Most drivers expect you'll ignore the stop sign and will yield for you. Some will refuse to go even after you're at a complete stop and got there after them, at which point it's a standoff. Doing a rolling stop (Idaho stop - illegal most places) ends up being the safest option most of the time.

In my state, there's a "dead red" exception, where a cyclist can pass through a red light under certain conditions.

Usually you can trigger the electromagnetic sensor if you ride over the edge of it; there's usually a visible seam in the pavement. You want to ride along the edge of the loop.

Good hack, but you shouldn't have to know how the hardware works to use the product safely. Good infrastructure/urban design should work without people having to think about it.

Around here there's a little white T-shaped line painted where you should roll your bicycle to trigger the light.

That does work most of the time, but I've found that once they pave over it with more asphalt, it becomes difficult to tell where the edge once was.

I have found that traffic lights with camera based detectors work pretty well in terms of detecting cyclists (without the paving over problem that loop detectors have).

Good to know, thanks! What gets me is that a lot of the automatic lights are of a different variety that works fine, and in some cases there's a bike lane up to a light that is incapable of detecting you (without switching lanes, at least).

I’ve never seen a detector like that. All the ones I’ve seen are mounted next to the traffic light and aim down towards where a car would be waiting.

They're very common where I live, but to the best of my knowledge they're weight-based so I'm not sure a cyclist would trigger it.

Usually it's a loop of wire embedded in the pavement.

https://en.wikipedia.org/wiki/Induction_loop#Vehicle_detecti...

When I rode a moped I would never trigger these things till I started rolling around with a large magnet zip tied to the bottom of my ride.

Hereabouts (Western WA), some cities have actually started painting the location of the sensor, specifically for cyclists. Here's an intersection in Redmond where you can see those.

https://goo.gl/maps/TRmyGzWZDAQ2

Around certain cities in the LA area, the striping crew paints a stencil of a cyclist and an arrow pointing forward over the sensor.

In the netherlands, bike lanes have buttons at the traffic lights much like the pedestrian buttons. We also have sensors and you can see if they worked with lights in the button.

I'm a cyclist and my behavior changes greatly depending on where I am and the time of day.

Riding through busy parts of town during the weekday? Hell yeah I stop at red lights just like everyone else.

7 AM on Sunday morning in a quiet suburban neighborhood? I'll probably look in either direction when approaching an intersection and cross without stopping if there are no cars or pedestrians around, even if my light is red. I'll still slow down a bit though, instinctively.

Basically my rule of thumb is this: obey all traffic signs as if you're a car if sharing the road with motorists, cyclists or pedestrians. Otherwise though, you can ignore the signs.

I wonder what would happen if all of the cyclists in NYC were to declare a week of staying in the vehicle lanes and obeying every law. By skirting congestion and clearing out of intersections, cyclists may be doing the rest of us a favor.

I remember when they adopted the 55 mph speed limit. Some truck drivers in Michigan decided to protest it by obeying it. The resulting congestion was pretty painful for everybody.

In SF, along a popular bicycle route called "The Wiggle", exactly this happened, and traffic ground to a halt.

https://archives.sfweekly.com/thesnitch/2015/07/30/this-is-w...

> I remember when they adopted the 55 mph speed limit. Some truck drivers in Michigan decided to protest it by obeying it. The resulting congestion was pretty painful for everybody.

Some people actually did this on an interstate near Atlanta, Georgia a number of years ago and posted it on Youtube [1].

[1] https://www.youtube.com/watch?v=OoETMCosULQ

That's a great story about the truck drivers "protesting by obeying the 55 mph speed limit."

American cyclists seem to feel so threatened by cars that they repeat a lot of the same unwanted behaviors they complain about. Maybe it's bad driver's ed, maybe it's the fact that there's no effort to teach cyclists the rules of the road in the US at an early age. Of course bicycling as an everyday transport is pretty common in europe, whereas cyclists make up a much smaller proportion of road users in the US.

In my view, what you're describing is a culture among cyclists, that is local to a few cities. For instance, cyclists riding like jerks would be a noticeable exception in my locale.

And there are other cultural differences between NYC / Boston, and my locale. For instance, I don't need a high security lock to leave a cheap bike outdoors for a few minutes </s>

I've personally received 2 NYPD citations for running a red light on a CitiBike.

The good news is that I now stop at red lights when I ride in NYC.

The funny part is that, several times, pedestrians have reacted with shock and glee, saying things like "wow, I've never seen a rider stop at a red light!"

I wonder if the cops can view the position of CitiBikes on their phone in real time.

I don't think CitiBikes have any location tracking. I think they only phone home at the docks.

I would think discussing the logistics of recovering the bikes would be an early discussion for such a project. Sooner or later someone is going to jack someone’s phone and steal a bike. And that advertising display device on the Citibike’s handlebars looks like an easy way to implement a GPS/cellular tracking system.

I'm in Austin and ride my bike to work whenever I can. I stop at all lights and stop signs. When I see other riders along the way, they are doing the same.

I moved here from Portland, OR and lots of cyclists there were way more aggressive.

Haha, here in Germany people will call you out for crossing a pedestrian red light.

That must be a regional thing. I have seen the odd cyclist run a red at T-intersections or go through a red after stopping at intersections controlled by sensors, otherwise compliance is near 100%.

I cycle and yes a few red lights get passed. Generally I stop but that is not a golden rule.

I also do a little bit of dog walking and have to cross the road with my sister's dog. Like yourself I was of the opinion that only cyclists jump lights, however, those same lights that I normally stop for (or perhaps not!), get routinely jumped by cars. I don't normally notice this when on the bike, but when waiting to cross with the dog I am surprised at how it is these motorists that do the light jumping. They also tail-gate each other through the lights after they have gone red at considerable speed. If they hit anyone then that would be a proper accident.

Ultimately it is human nature to want to jump lights and how educated someone is.

I was in lower manhattan during the huge northeast blackout 14(?) years ago. I can confidently report that turning off all the traffic lights in the city did not lead to improved traffic flow.

We seldom obey any traffic signals/rules in India to the point that turning them off doesn't make any difference

Exactly what I had in mind reading the title. The answer to several "what happens if we dump this system that should organize our society" question is - look at India and you'll find out.

Apparently with enough gods anarchy works.

Obeying traffic lights decreases tail latency and increases throughput. By not obeying them (as a society, rather than individual), India is only hurting itself.

Heh. I was thinking, based on my somewhat limited experience driving outside the US, that turning off traffic lights in Rome or Bangkok would have only have an effect on tourists, making them aware that there are no rules.

The discovery in this article will seem quaint if you've ever crossed the street in Southeast Asia (there's never a break in traffic, so you cross anyway and the scooters flow around you, https://youtu.be/LlyOom0bwwY)

> Behaviour was noticeably different. Most cyclists slowed down as they approached the intersection, and communicated to other cyclists and motorists using eyes, gestures, expressions, and voices. A lot more negotiation was taking place – but not without friction.

What happens is heavily dependent on relative traffic flows.

If it's sparse, not much bad happens, there might be more bad accidents from people assuming right of way. If it's heavy in all directions, people going straight or turning to whatever side of the road they're on will be reasonably OK, while people turning across traffic will have a bad time. If it's heavy on one road and light on another, the light road will be starved of exit opportunities.

Turning off lights certainly isn't a panacea. Anyone who's lived in a city for a few decades will remember junctions that got much better with the addition of lights, and junctions that got worse. Some will recall bad accidents (T-bones and the like) that prompted their installation. Etc.

A consequence of this model that one perhaps might not anticipate... India is this taken to the extreme. To assist in the "negotiation in motion," all the vehicles use their horns constantly. Beep beep beep. It's not considered rude, more like sonar. But it is a lot of noise pollution.

I take this road every day when I go to the University of Amsterdam's REC. It was very odd at first and they worded it as if it was a short-lived experiment, but then the lights never returned. To be fair, it's amazing.

It's important to keep in mind that one of the attached avenues is a "cyclist priority" one, where the cars are essentially "guests" on the road. That avenue doesn't get as much traffic as the other entries, so it was already very suitable for such change.

Where I lived in a suburb of Los Angeles, we’d have inexplicable traffic light outages. Well, some times it was due to rain. Invariably traffic would be backed up for half a mile. It was terrible.

As others have pointed out, solutions that work in Amsterdam, may not generalise to other parts of the world.

Over the last 15 years, a combination of power cuts, shoddy maintenance and cable theft have made traffic lights a lot less reliable in South Africa.

In some cities, like Johannesburg, drivers tend to follow the rules regarding broken lights, and treat them as four-way stops. In others, such as Durban, I’ve seen drivers barrelling through at high speed, hoping for the best.

Given the apparent wide geographic variation in dealing with this sort of thing, perhaps a more appropriate title for the article should be “What happens if you turn off the traffic lights in Amsterdam?”

I would like to see this normalized for the position on the political spectrum of the government in power at the time of any test.

I felt that people's driving style changed immediatly when there was a change of government in the UK.

I read an article a few years ago about a town in the UK that did the same thing and reported the same results, an increase in civility and a decrease in accidents.

> Nearly 70% of all city centre trips are by bicycle, and more space is needed on the bike networks.

Yes, please! I want that where I live. It has been improving, but we have a long way to go. I really hope more US cities end up with majority bike/ped traffic rather than majority car traffic.

Geography may not be conductive to biking everywhere. While I mostly bike around the city I live in, it's a very hilly place and even a short trip requires an amount of effort that cannot be expected of most people.

As for pedestrian traffic, my experience with medium US cities is that they are far too spread out for walking to be an option for most things. It's hard to see how this could change without Americans abandoning their beloved individual suburban homes with yards.

I think in most places public transportation is the only effective replacement for cars.

All true! I agree, and hilly is a problem.

I could see cities easily changing though, by slowing the outward growth and becoming more dense... and more bike-friendly in the center! ;)

The city I live in has been growing outward, but that's coming to an end now that the expansion in the valley has hit the mountains on every side. The good news is my downtown is getting more bike friendly every year, I'm just looking forward to bikes being a majority. (Which might never actually happen since it snows where I live...) :)

Get a ebike. I live on a street with a 8% climb and that on a ebike is just a stroll. My wife loves it. Most of my cyclist neighbors have one too. I occasionally “steal” her bike, but most of the time I love doing my climbing by myself. Though things may get hairy above 12% and definitely painful above 16%. However, with a ebike even those gradients would be fine.

Sure itself regulates, because people have a survival instinct. I can tell you from experience however, after the massive wind storm of 2011 in LA, when every signal was dark, it turned my 11 mile commute from downtown into a 90-minute affair, with an exhausting cognitive load because of the constant concentration required. The commute ranges from 20-40 minutes (typically 30-35 at rush hour) when the signals are on.

"...at one particular intersection" ...should be added to the headline.

We rely and place so much trust on the traffic system to do all of the decision making work. We just follow its orders. But what if the system experiences a failure unexpectedly? Accidents probably will occur, traffic grinds to a halt. I have been in a situation on a highway intersection where the light was stuck on red and it was a horrible experience. This is the problem with a centralized traffic system. I have noticed that even I have started to place too much trust in the walk signals while crossing streets. I have caught myself failing to look both ways. While its nice that the traffic system reduces some cognitive load, It's not 100% working in favor of our safety. I think the US ought to conduct more experiments like this to see if traffic accidents can be reduced. I'd like to see an experiment in NYC! So many bike accidetns here.

I think a big part of this is momentum. When the majority of people were excited about cars and saw them as newer and better than bicycles, you would get treated like shit. See most US cities. When the majority of people begins to understand that cars weren't the panacea they were expecting, then you might get more respectful behavior like that in the Netherlands. Here in the Dominican Republic being a pedestrian is "for the poor." Cars rush towards you—and you either get out of the way or join the roadkill. So what happens if you turn off the traffic lights? Depends whether people cared about them and safety to begin with.

It obviously wouldn't work for all kinds of intersections or traffic types, but it is great to hear that good natured human cooperation was the key to this success.

Given a shared obstacle, people seem much more willing to coopetate and make concessions for others and help others achieve their goals. I notice it when the power goes out here and signals disappear. Even though it's 100% car traffic and two lanes in either direction, people were still able to negotiate with eachother to make it work, if only briefly.

I imagine years of conditioning for bicycle heavy and bicycle friendly infrastructure was also a huge factor for the success in the article.

This is the way of the future for flat cities in temperate climates where most people can cycle. But Holland is an extreme case where disciplined drivers are educated to respect cyclists. Don't expect this to work anywhere else, anytime soon. Holland is the future, but it your backward community cannot adopt this tactic without a long hard battle against the entrenched arrogance of the car driving unintelligentsia.

This isn't a unique experiment. I remember reading about a German city (Drachten) doing it about a decade ago. http://www.spiegel.de/international/spiegel/controlled-chaos...

There is certainly a German place also doing this which the article mentions but Drachten is a Dutch city :)

Doh! Thanks. Should have Googled it.

Just went through traffic light outage due to Irma. Traffic was not improved.

I want to say as a person who had no lights working due to Irma in Miami, North Miami etc traffic WAS improved.

Instead of waiting 2 minutes or so as usual, I was on my way in about 45 seconds. Yes I had to be more aware but it was worth it.

This would've been a great initiative if it started 15 years ago. At the moment, I think changing traffic systems in ways that are less accessible for self-driving cars is short-sighted.

A self-driving car that can't handle a missing stoplight isn't production-ready.

After several hurricanes - you should treat them as 4 way stops, however a large chunk of people just run through them (most recent example is from Irma)

It could be so easy- if everyone treated intersections as roundabouts..

Imagine this in New York City...

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