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> This is the only case in Germany where this law makes no sense.

Actually, there are two more permanently red lights in Dresden alone. They are mentioned at the end of this Video: https://www.ndr.de/fernsehen/sendungen/extra_3/Realer-Irrsin...

Geil

> Dresden is one of those rare german towns with US "Rechtsabbieger" rules

If it's anything like the picture, the reason right turns are allowed is the green arrow (it roughly translates to "when red, right turns are allowed if you don't interfere with other traffic"). I strongly doubt random towns in Germany can bypass the StVO (the laws which govern public roads).

EDIT: To clarify, I was born in Cologne, which is on the opposite of Germany, and green right arrows exist here as well and they are part of the material you learn for taking a driving exam.

Dresden is not allowed to bypass the StVO, so they had to put up this crazy light, yes.

But the Rechtsabbieger "Grünpfeil" is also in the StVO § 37 Abs. 2 Nr. 1 Satz 8 bis 10 https://de.wikipedia.org/wiki/Gr%C3%BCnpfeil

History: The old DDR came up with this Grünpfeil (turn on red) law. During the Wiedervereinigung it was "agreed on", that this law can persist for max. one more year, 1991. But based on huge civil protests on silly law reforms (same for abortion and women rights which where more advances in the east), Germany kept this exception, and even some old ex-BRD towns introduced it since.

I believe Dresden had most of the existing 2.500 Grünpfeil signs in Germany, but in the meantime the west has caught up, and there are now 5.000 such signs.

Grünpfeile were really new in West Germany after the reunification. My brother told an anecdote from when he once drove through Hamburg and saw a Grünpfeil there, which had a sign below it explaining how it worked (something like: "Grüner Pfeil = Stoppschild für Rechtsabbieger", "green arrow = stop sign for right-turning drivers"). He quipped that this was probably the only traffic sign ever to come with its own manual.

Unlike in France, where for some reason a lot of symbolic signs come with text instructions on a separate sign:

http://s3.freefoto.com/images/41/03/41_03_88_web.jpg

(English: "Give way")

The same is true in the United States to a certain extent, though the instructions are a bit more complicated usually. The Yield sign and the Stop sign will have the relevant text within them, but below those signs you will have instructions for the given intersection, especially with stop signs:

"4 Way" or "All Way" -- Indicates that every entrance to the intersection has a stop sign. I understand all way stops are either uncommon or unheard of in Europe.

"Cross Traffic Does Not Stop" - often used with "Two Way" stop

"Traffic from the left/right does not stop" -- often used when one direction is coming off a signaled light or crossing railroad tracks, or other cases when traffic from one direction needs to continue to flow to prevent a backup that could be dangerous.

Crosswalk signal instructions regulatory sign -- https://commons.wikimedia.org/wiki/File:MUTCD_R10-3b.svg

Judging by what I've seen in photographs, the instructions on US signs often either state what should be obvious or are unnecessarily complicated (often because there are unnecessary exceptions other countries would simply omit).

Actually that's a really nice way for people to learn what traffic signs mean, way before they start studying for a driving license.

I don't own a driver's license either. I just pick this stuff up. Sometimes I ask my current driver what a certain sign on the road means.

Or you could teach it in school. In Germany we had bicycle excursions in school, including a mock "cycling license exam" where we drove on a test track with various road signs and traffic lights.

Is this one ever used? http://radyzezivota.cz/wp-content/uploads/Dopl%C5%88kov%C3%A...

This is the normal sign, yes. But in some towns (esp. Dresden, but now everywhere) we have simplier ones, a green arrow without light. You are allowed to turn right on red then, if traffic allows. Similar to the US.

https://ais.badische-zeitung.de/piece/00/bb/82/9b/12288667.j...

Yes. The difference is that the lighted version does not require stopping (because it's only lit when there is no cross-traffic anyway), whereas the static sign does require a stop before turning.

This. I was actually unaware of this distinction before studying for the driver's license and always assumed the sign was just a stylised version of the light to save energy.

Also worth of note: when traffic lights are active they always take precedence over static signs which in turn take precedence over road markings (which themselves take precedence over road layout). The green arrow sign is special in this regard because the rules for traffic lights explicitly take it into account -- otherwise the red light would always trump the sign because of precedence rules.

Not in this form, no. The green arrow light would be required to be next to the other green light in this case (in Germany at least). But those do exist, yes.

So IOW it's not so much that Dresden is one of those cities with American laws but that they make more use of that German (originally East German) law that is these days commonly made use of throughout all parts of Germany even though Dresden still features them more prominently?

Sorry for nitpicking but your first post read like Dresden had special traffic laws and green arrows were rare outside a handful of cities (plus AIUI the green arrow has slightly stronger implications in the US).

Yes, I was unclear.

fwiw, in the US you can turn right on red unless there is a sign saying you can't... I've never seen a green arrow sign. Sometimes there are green arrow lights that say you have a protected right turn.

Not in New York City, where you may not unless specifically marked so.

good to know... how likely are you to get pulled over for turning right on red illegally, but safely?

All the time. It's a surefire way of pulling over someone from out of town. My first ever memory of being pulled over was visiting NYC. My dad was driving and got pulled over. The cop said: "no right on red in New York City!" - a phrase that is now burned into my memory.

Occasionally it will be screamed at you by pedestrians in Manhattan when you edge out and block the crosswalk.

You are 7 likely...

But also importantly, it is allowed in New York state, just not the city. Very weird.

NYC should secede from NYS.

Is there a more complete overview of this traffic situation somewhere? I still find the reasoning a bit hard to understand.

I understand that from this road, you can only ever turn right, and can do so at all times, so there's no need for a traffic light, except that it legally needs to have one because other roads at the junction need traffic lights for other reasons.

So what are the other roads here? Clearly it has to be more than just the Ziegelstraße and the Güntzstraße.

I think this is it: https://goo.gl/maps/uLpY8kjjJFw

Ah this makes the whole thing so much clearer. Thank you. (Why couldn't the article have this?)

https://www.google.no/maps/@51.0539102,13.7575856,3a,75y,78....

What happens when someone from somewhere else comes to this light? Do you see tourists stuck here?

I think for most tourists the green arrow next to the red light should be suggestive enough.

Tourists don't come that way. It's very small residential street, turning into a big street with lots of confusing signs and disallowed directions. For me the much worse problem is the other way, coming down the Güntzstraße to the Elbe. The whole crossing is a real city planning nightmare, and I worked in city planning for some years.

The streetview image posted by advisedwang shows there's also a white-on-blue "must turn right" sign at that junction. This ought to make it clear that you shouldn't wait there to go straight.

Except that the traffic light takes precedence over the sign and thus the sign has no effect whatsoever as long as the traffic light is active.

No, it would take precedence if it had an arrow painted on it, but as it's just a traffic sign, it only controls entry into the intersection, not where you can go.

> But hours can not be the only cause for problems, and while we are there and there's a budget for replacement, we'll do it all together.

what does it matter if the green and yellow bulbs are broken? They'll never be turned on.

I think the point is the bulbs are cheaper than the (a) cost of developing, deploying and tracking a one-off maintenance protocol change and (b) risk the instructions are applied to the wrong intersection.

This. And they rules may change, and someone might decide to turn them on someday. They are prepared then :)

It should be obvious if the light doesn't have ANY yellow or green bulb that they shouldn't be changed.

Usually we teach people to not try to be clever when applying checklists. More often than not the "obvious" thing to do can have fatal consequences.

Or maybe the last person forgot, or they were stolen, or whatever. You'd probably have to report that and waste the time of a bunch of people.

surely it is illegal to put up a traffic signal without working bulbs.

If the traffic lights on that intersection are off or go into that mode due to other reasons you'd have a yellow blinking light.

Hey, so just to clear things up, because nobody seems to have mentioned it: Is there a sign indicating that there are only right turns allowed? (White angled arrow pointing right on blue background)

As a driver approaching this particular crossing while seeing I'm only allowed to turn right I'm not sure I'd ever notice the light staying red indefinitely.

There is such a sign, but it's irrelevant as long as the traffic light is active so you can just ignore it. The whole intersection is also built in a way that you can really only go right as there is nowhere to go straight ahead or even left. And you surely would notice the green arrow sign next to the red light and act accordingly.

You could have mentioned, that the traffic light doesn't exist anymore: http://www.faz.net/aktuell/gesellschaft/ewiges-rot-an-dresdn...

I also do remember somewhat fondly when Dresden still had actual police officers regulating traffic by hand. It's been some time since I left Dresden and I don't remember the crossings. Oh, and the frequent power outages..

Okay, the law requires a signal light at that intersection. Okay, the light is always red because reasons.

What I don't understand is why the 3 light red/yellow/green signal unit has never been changed to a 1 light red-only unit.

Perhaps because it wouldn't "look like" a traffic light and so would be potentially confusing ("Wait, do I have to stop for that, or can I just turn?").

I know I've seen single lamp traffic lights before.

Like this one....

https://c1.staticflickr.com/3/2041/2234314943_bdcd95d800_b.j...

Those come with a "stop" sign as well and are usually seen on high speed highways as a way to get drivers' attention long before the sign comes into view. This intersection has a yield sign. A blinking red "stop" and a yield can't go together can they?

A blinking single bulb red light is the same as a regular 3 bulb traffic light red light, with the exception the 1 bulb red light on/off is programmed with a shorter periodicity. Take a blinking red and make it a solid red. Obviously, they took a 3 bulb traffic light where the red light should be turned off periodically and programmed it to show continuous red. A continuous red light on a 3 bulb red/green/yellow traffic light is abnormal behavior for that type of traffic sign.

so could someone just sit at the stop light to just annoy the other german drivers and police?

An aquantance of mine wrote a peice of software that looks at satelite pictures of Prague at night and tells the city which street lights are out, so they don't have to use a "regular replacement schedual" but only replace the bulbs that need it. Could the same thing not be done using red-light cameras and stop lights?

Hey, that's a good idea - exception catching for traffic lights

Replacing a traffic light after it already failed is too late.

Not in London. Nearly every day I see a new failed one. There is usually redundancy tho

That seems like the right approach. The traffic light has a backup bulb and alerts when one burns out. I mean, cars can tell when a bulb is out, right? Why shouldn't traffic lights.

Actually it's even simpler than that, just have a minimum of 2 lights per direction of travel.

So if one fails, a bulb burns out, one gets destroyed in a storm, or anything else happens, there will be at least one full backup.

Having automated outage reporting still makes sense though. It keeps you from having a guy that's paid to check every light in the city manually. And since your lights are on a city-wide network (they are, right?), then adding outage reporting should be a feasible thing.

It might or might not. This is a costing exercise where you need the understand the objective and cost factors.

If you have a strong requirement to avoid failure, proactive replacement let's you optimize the unit cost of replacement because you can fully utilize the crews and have no wastage.

If you dispatch reactively, you either have people sitting around waiting for light bulbs to burn out or lightbulb replacement pulls crews off of other work, impacting schedules.

...or you could hire contractors when you need to do bulb replacement? Then you have full utilization while you're replacing bulbs, no one is idling on your payroll while you're not, and no one gets pulled from their existing work to do replacement.

... and the external contractor who you're pushing all that risk on will charge you appropriately.

Sure, but they only receive the full amount of the risk you lose if you are their only client. They're still cheaper than either solution I responded to.

That's an option too, but is more complex and less deterministic.

The key assumption is you want low/no downtime. The problem you have is negotiating SLA penalties are difficult to get right for organizations like cities and getting good metrics are tough.

The other thing, especially with government contracting where RFPs are extremely difficult to change after the fact without getting contracts disputed by the losers is that the contractor will add risk premiums for penalties.

In the UK the device managing the junction can already detect most failed lamps, it's common in safety applications to have paired filaments, so when one fails the other still works but you can detect the problem. People selling a city devices to manage their traffic offer the feature of the city being informed about failed lamps. But, that costs money and saving money is important in most places, so they'd rather wait for motorists to report a failed junction and repair it after the fact versus paying extra to solve it first.

As things move to LEDs it hardly matters anyway, a correctly engineered LED lamp doesn't suddenly fail like filament lamps, it just gets sort of dim gradually, so a regular schedule (e.g. replace all the LED lamps every 5 years) is the correct way to deal with it. Cheap consumer-grade LED modules sometimes fail suddenly due to over-heating or badly made electricals but the road maintenance people probably aren't buying unlabelled stuff off eBay so they're unlikely to have that problem.