Could we do without traffic lights? | Hacker News Reader

Could we do without traffic lights?

bbc.co.uk

30 pointskfullert43 comments

Interesting POV -- you can get away without traffic lights in the country or in places where other forms of transit (ie. public transit & walking) are more prevalent than cars. You can do so in the city as well, by installing expensive street features that have huge downsides in snowy climates. But, many of the arguments used by the advocate in the story are bunk.

An example re: Pedestrian accidents: "People think traffic lights are a guarantee of safety but the latest audit from Westminster City Council, for example, has shown that 44% of personal injury accidents occurred at traffic lights."

Sure. Pedestrians generally cross the street at the crosswalks, which are placed next to traffic control devices. And many of those accidents are at intersections that lack directional control -- the driver doesn't pay attention, turns right and hits someone crossing the street.

The guy is right about a few things -- the regime of controlling traffic and handling peak demand is very inefficient. That's a feature of urban sprawl.

The problem with cars is that you get the "network effect" with respect to road capacity. Unlike computer networks, expanding capacity is alot harder than pulling a cable. Plus, if you have a two lane freeway or bridge, and you expand it to three lanes, traffic patterns will adjust and congest that road again. The New York City metropolitan area is a great example of this -- the driving suburbs of NYC extend nearly 75 miles north of the city at this point. People on Long Island literally commute over 2 hours to get to Manhattan via car and train.

If nothing else, please could we stop people putting traffic lights on roundabouts, as the one defeats the entire point of the other.

I think in most cases yes, but some I come across the sheer weight of traffic on the roundabout (at peak times mainly) means that no traffic would be able to join (say at a junction immediately prior to a major one which has 99% of traffic on the roundabout passing it and making the traffic waiting, keep waiting)

Which leads back to: Why is there a roundabout in the first place?

Huuuge roundabouts with traffic lights should really be good old-fashioned crossroads. Those take less space and work fine. Roundabouts tend to be a better solution _if you don't have the constant flow of heavy traffic_.

I agree with the gp: Either a roundabout xor traffic lights.

I never understood that either. What is their reasoning behind it?

So when can pedestrians cross?

Just add a zebra crossing.

Hell yes! Marcus Povey for mayor!

This is one of those things that just annoys the hell out of me.

In Ann Arbor Michigan, they've been installing roundabouts in many junctions [1]. My next door neighbor is a landscape architect and is a huge fan of them -- they virtually eliminate fatal accidents. Roundabouts normalize traffic, creating a continuous flow of more evenly spaced cars with overall greater throughput. With islands in the middle, they are much safer for pedestrians.

There are two downsides. They really require much more space than a traditional intersection. They also remove "traffic gaps" between major streets that permit people to make a left hand turn out of a neighborhood.

He's not a huge fan of 2-lane roundabouts. They create an incentive for drivers to cheat by driving down middle of both lanes, staying at 35/40 rather than slowing down to 25 go around the round about. They also cause confusion when someone gets into the wrong lane (left/center lane must go straight through) and this reduces throughput. Perhaps there is a minimum/maximal traffic where they work effectively.

After using roundabouts at nearby intersections, I'd also add that they are much more attractive. Waiting at a light causes stress (and people tend to "text", causing more delays). Given the chance, I prefer to take routes that use roundabouts. I've timed them, and they are faster and more consistent then traditional 4-way-lights, especially at intersections where left/right hand turns normally cause traffic backups.

[1] http://www.annarbor.com/news/roundabout-planned-for-geddes-a...

Roundabouts are great in suburban or low-volume urban environments where speeds are low.

But they can be dangerous for pedestrians in areas where you have a high density of traffic and pedestrians.

The problem is, transit planners tend to think of terms of making things flow well for suburban commuters going to work in the city. They tend to forget about the folks who live in the city.

In my city, there is a roundabout with five junctions, although I find most roundabouts fine, I really don't like this one. During peakhour, you can have long wait times, much longer then a respective traffic light. Another interesting thing about this roundabout is gaps in traffics caused by other traffic lights determine which road is currently a main outlet.

We'll be able to remove traffic lights, signs, yields, stop signs, and every other limitation... Once the Google Self-Driving car becomes universally adopted. As long as the car itself is able to perfectly judge for safety, and possibly communicate with other cars, then there's no need to stop when the car knows, for a fact, that there are no other obstacles around.

Of course, that's still very far off!

I used to argue that insurance companies would push for them, because self-driving cars would reduce accidents.

But the cynic in me wonders if they will be afraid that self-driving cars will push insurance costs down so much the insurance companies will lose out.

While the costs may go down and people's premiums will likely go down commensurately, accidents will still happen. So most people will carry insurance for that purpose. And besides, do you really think the insurance companies are going to let the state governments make casualty car insurance not required? Or do you think the car loan companies will really drop requiring comprehensive coverage as a requirement? I think not.

I don't buy it. Especially this:

"Instinctively, we want to be kind to each other, especially out on the road. When you first meet a stranger, unless you're a mugger, you want to be nice to that stranger."

The author himself admitted a couple paragraphs before that he really wanted to speed up at a traffic light instead of stopping, thereby risking running a red light. This "Don't want to wait" is one of the many examples that come to my mind and contradict this "We're all nice, deep down in our hearts" idea.

You can remove traffic lights - if you reduce cars to a crawl/make them the least priority. Treating pedestrians and cars as equals won't work in my opinion. Betting safety on a hippie idea [1] doesn't sound compelling either.

1: To be fair: I _like_ the idea that we're all just totally trying to be nice to each other. It's just .. very much not true in my experience, especially among strangers.

Sorry. That was one of the worst things I've read this week. The jumping to conclusions, the unstated assumptions. The gross misuse of statistics. I love the one about 44% of pedestrian accidents happen at traffic lights. I think it was Willie Sutton, the famous bank robber, who said he robbed banks because that's where the money was. If pedestrians cross in crosswalks that's where you're likely to hit them. Because that's where the pedestrians are. Oy! Don't get me started. It was seriously put forth a few years ago in Berkeley that all crosswalks in the city should be erased on the theory that pedestrians become "overconfident" in the crosswalks. The evidence given was that cars hit pedestrians mostly in the crosswalks. Luckily the traffic engineer who proposed this took a job in the suburbs.

The author should visit the busy streets of north India - specifically the NCR region and see what happens when the red lights are not functioning. I have faced such situations and have been stuck for up to an hour for the jam to clear up. Per my own personal experience, traffic lights are a must.

I commute quite heavily in the UK, and there are certainly places I can see where traffic lights are either completely surplus, or could be reduced to peak-operating only, and there are other places where it would cause worse problems if there weren't traffic lights in place.

There could be cultural differences at play here I suppose. The British seem to have a knack for queuing which may be missing in other cultures.

I live in South Africa, and I have definitely seen improvements in traffic when certain lights are out during rush hour (4-way stops on highways in particular).

I agree with the knack of queuing being missing in different cultures. In Malaysia, when the traffic lights go out, it's absolute deadlock.

My commute route also takes me by a few traffics semaphores. I can tell if they are not functioning properly (flashing red only) by the long backup.

During heavy traffic at commute times, the lights facilitate semi-smooth traffic. Off peak and I see where they interfere -sometimes they turn red on you, even though there is no cross traffic.

Also, conversely, there are moderate-traffic intersections which only have stop signs. I hate them. I wish they'd put in some quick phase traffic lights to smooth out traffic.

Some of the worst jams in Mumbai I've experienced are when a policeman decides to direct traffic at a junction rather than let the lights do it...

"I knew it would be a long wait at this set of lights."

As an odd hobby of mine I like to watch the clock when I get to a traffic light to see how long I actually wait. I don't record it but I am amazed how often I only wait about 1 minute. I think the facts are much different then everyone's perception.

I think 1 minute is probably about the average wait in off-peak traffic (I'm going to have to start timing how long I sit at lights now) but on my journey I pass through at least 10 sets of traffic lights - waiting for 1min at each of them adds 10mins to my journey (admittedly I don't wait that long or even at all at most of them) but the potential is there

Spend a week driving in a college town and decide if lights are a good idea or not.

Everyone whipping around in 3-ton SUVs, texting and yammering away on the phone while they drive.

Just feel fortunate the do mostly stop at the lights when you are coming the other way.

I wonder this every time a light goes out and I see people carefully and considerately coordinating to take turns at an intersection. But I really think if that weren't a special case that got everyone's attention, the result would be more collisions.

They don't talk about pedestrians at all here. Lights might be annoying, but it's also seriously nerve wrecking for all involved when dealing with a pedestrian crossing without lights. As a pedestrian trying to cross, it's often difficult to judge the driver's intent, even if they are slowing down, so I'll end up staying off to the side until they stop completely. Needless to say, that's hilariously inefficient.

And when it gets dark, it just gets worse. It might be possible for the driver to see the pedestrian pretty well, but the reverse isn't always true.

"The fatal flaw at the heart of the system is priority. [...] The unseen spanner in the works is the idea of main road priority."

He fiddles a bit with a story about a woman and a pram, but doesn't actually address why this is a bad idea. While access and crossings can be improved in places, letting traffic flow fast and freely on main roads seems like a fundamentally good idea to me?

As a driver I can understand why removing traffic lights makes sense in some regards.

However, I spend less time driving than I do by my usual form of transport, walking, and frankly there's a minor subsection of drivers who are bad enough as it is (case in point, how many jump zebra crossings).

Maybe it's just in need of disruption, adaptive pattern systems and such.

I've heard some Spanish traffic lights are quite "smart" for traffic control (these are mainly on highways rather than junctions/pedestrian crossings) where if you travel at or below the speed limit, the lights are green, speed and they go red thereby giving a positive association for not speeding (ie if you don't speed, you and everyone else travelling the same stretch probably get there faster - make everyone stop as you're speeding and most likely people won't be happy)

They have them in a lot of European countries, we call it "the green wave".

There's also another trend on the rise: cameras that take photographs of license plates at an interval of several miles. If the calculated speed (the average) is larger than what's permitted you get a ticket.

Yes, we have those in the UK called SPECS (http://en.wikipedia.org/wiki/SPECS_%28speed_camera%29) although these are generally (only in my experience) used temporarily in roadworks etc. which have a temporary lower speed limit.

I believe France did this the low-tech way in the past with toll roads (get a ticket with the time when you enter a toll road, pass it to the booth when you get off, S=D/T and caclulate if you have a speeding fine to pay as well)

It's bad enough with traffic lights [1]. If you take them away, then it's like an idiot free-for-all out there...

[1] http://www.liveleak.com/view?i=854_1337054851

Your logic is lacking. The car in that clip is driving without the least regard to reasonable behaviour and the law. He was not stopped be the presence of traffic lights. Are you suggesting that he would be less not stopped by the absence of traffic lights?

Or as the article puts it:

"You can't even legislate for maniacs, so why hobble the vast majority with "one size fits all" rules devised to catch the hypothetical deviant?"

Fucking logical pedants.

Less not stopped is logical and correct if you consider the individual. If you read the comment again, it does not exclude other drivers so the logic is correct. The comment was not inclusive.

Perhaps I should clarify: "If you don't apply the one size fits all rules, you will increase the number of deviants."

Now there is a logical fallacy there for you to ponder...

Happy now?

bangs head on wall

You seem to assume that the only reason people stop for red light is the law. Considering that plenty of non-lighted intersections exist and people behave reasonably in them, I don't think that's a reasonable assumption.

No the only reason people stop is that they read the highway code and therefore agreed a set of conventions to work with other people. The law (Road Traffic Act 1988+) is the enforcement of such a thing and is a separate problem.

With regards to other "intersections", in the UK where the They have give way lines across the front of the junction so they are "controlled" as well.

When they are not controlled, it is carnage as the numerous bits of missing car brushed to the side of the road demonstrate (look carefully).

The reason people read the highway code is because it's describing what the law is. It's meaningless to treat the highway code and the law separately.

I believe that the vast majority of people behave in traffic, not out of reverence to a book, but because they want to arrive at their destination safely and without having hurt other people.

Wrt. other intersections (not sure why that word needs scare quotes?), I live right next to a fairly busy one, and can see three others from my balcony, and I have so far failed to see any carnage.

There are varying degrees of maniac/deviant. Lots of drivers routinely change lanes without signaling, cut other drivers off, refuse to wait for pedestrians standing at the crosswalk, etc. There aren't nearly so many who routinely run red lights.

People aren't naturally nice to one another around these parts.

But what would make it work is people's desire to not deal with a crash and its fallout. That's a personal loss no matter who is at fault.

Traffic lights in its current form will be obsolete by the time AI / computers start driving all our vehicles.

We (everyone reading this) will be dead before that happens. Not because the technology won't be there but because making auto-driving cars mandatory won't fly culturally/politically, certainly not in the US.

We'll have optional self-driving Google-car style cars soonish (maybe 10-15 years out when you factor in all the regulation hurdles), but they won't be mandatory for a very long time, if ever, and if even a small percentage of people opt out of the automatic driving system we still need the current control systems and road rules in place.

imho, changing the habits of drivers would be extremely costly.

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