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Collision Course: a type of road junction that is dangerous for cyclists (2018) (singletrackworld.com)
144 points by ColinWright on April 29, 2020 | hide | past | favorite | 141 comments


Someone saw the Tom Scott video about this from a couple of days ago? https://www.youtube.com/watch?v=SYeeTvitvFU


Strong sense of deja vu. I've seen something about this before, and I think it predates the Bez article this is based on.

https://singletrackworld.com/2018/01/collision-course-why-th...

I don't recall the colors on the pavement.

Constant Bearing, Reducing Distance, mentioned farther down, is a naval concept, and if memory serves this is part of the protocol for lookouts (people standing in different places have different CBRD blind-spots).

I've seen this with my partner a few times, where some object is not exactly behind the A pillar but just close enough to it and maintaining a constant bearing, meanwhile she can't understand why I didn't see them coming (once in a while the shoe is on the other foot, and I yield for someone that she didn't see until the last moment).


Is it somewhat ironic that at :15 seconds into the video a car hurls through a stop sign?


At 1:26, a car rolls through it too. Quite as a few, as he sort of points out near the end.

I like this as an example of a problem that can be solved by engineering far more easily than by changing human behavior.


Another solution is to block off the eastern exit, turning it into a T junction. It's low traffic, there are multiple alternative routes and the road to the east is short and insignificant. This technique is used a lot in towns nowadays to shut off dangerous junctions onto arterial routes (and to prevent 'rat runs').

The alternative route round works out at 5 minutes longer but in a national park that's pretty good, and the lives saved should be worth it. Map view here: https://www.google.co.uk/maps/place/Ipley+Manor+Stables/@50....


An even simpler solution that I have seen implemented on some open field crossings is to deliberately block the view line somewhere close. It doesn't have to be blocked on the entire approach, just enough to ruin the illusion of having sufficiently observed the entire crossing road. It could be a billboard with traffic safety propaganda (or ads), some greenery or a stack of photovoltaics. Not much bigger than a bus usually.


this solution is actually discussed in the article and dismissed because it would be very visually intrusive with the rest of the forested land and because careless drivers might still only give a quick glance after not seeing any cars while approaching the junction from far away.


Right, they presume that the entire approach would have to be covered. But the parent asserts that a short fence would be enough. (I'm inclined to agree.)


I'd agree with that. Even something to "break up" the view and add ambiguity might make people stop... the road equivalent of a scarecrow, perhaps.. some "scarebikes"? :-

(I've seen a lot of cardboard cutouts of police officers at various petrol stations in recent years. They do make you think twice when you see them out of the corner of your eye.)


Same principle for tight city streets being safer than wider open city streets. It makes the limits of your perception more obvious and (hopefully) puts you on alert and engaged in the driving. It doesn't actually make it any more challenging to drive, it's just making the reality of the situation more clear.


I agree with you, this is the best almost no cost option as there is such a close detour route and there is so little traffic coming from the east. I'm surprised this wasn't offered as a solution, all it would take is a barricade.


Something to add to this is that 'stop' signs are pretty rare in the UK compared to somewhere like the US. People wouldn't be expecting a 'stop' sign at a junction like this, so they're expecting to yield, and due to the blind spot they think they are yielding.


> People wouldn't be expecting a 'stop' sign

It's bright red!


Most drivers are taught to assess the junction before they arrive and decide if they need to come to a stop or not. The thought process in the heads of drivers approaching the junction is "I have good visibility in both directions and there are no other vehicles. I will go through." This works for most situations but fails tragically here.

Yes, the drivers should stop for the stop sign but they clearly don't. It's a UX problem. The junction should be fixed not the user.


If the the training encourages you to ignore signs and signals, that's much more than a UX problem.


The training doesn’t teach you to “ignore signs and signals.” The point is that the overwhelming majority of junctions of this type are marked Give Way, and the trained behaviour on a Give Way junction is to slow and take careful note of other vehicles, but not necessarily to stop. Full Stop signs are very much more rare in the UK than in the US and where they are used it is typically at completely blind junctions. Because of that, many drivers’ brains will subconsciously recognise this as a Give Way and act accordingly. Which is careless, but ultimately a UX issue.


If the thought process is "that's a give way sign, I'll do the give way thing", then that's a UX issue with the sign. If the thought process is just "I'll do the give way thing" then that's also a major training issue.


It can be fixed with better training, infrastructure changes, or both. The cost of fixing the training regime would be extremely high, however: New drivers presumably already know what to do and have been tested on it during their practical exam. The problem is that encounters with stop signs are sufficiently rare they fail to naturally reinforce that training through repetition. To fix that, you either need to increase the frequency of natural stop-sign encounters by installing more of them or to introduce artificial encounters by requiring practical exams for license renewals.


> It's bright red!

I'm not saying it isn't.

But in the UK most junctions are yield, so drivers don't approach junctions thinking 'I might have to stop' they think 'I'll have to yield', so if they aren't paying attention their default is to yield.


Are there not multiple warning signs there's a stop sign ahead?

The MUTCD version: https://upload.wikimedia.org/wikipedia/commons/7/7d/MUTCD_W3...


I think that's an American sign. The context of the article is the UK. We don't that exact sign in the UK. I think there is a 'stop in 100 yards' sign but I can't recall ever seeing one. But the point was people aren't paying attention to the signs... so another sign doesn't solve that.


MUTCD == the (American) Manual on Uniform Traffic Control Devices, it was intended to demonstrate what I was talking about.

If you add multiple (large) signs ahead of the actual control device, you'll have higher compliance, since the unusual sign doesn't appear out of the blue.


Maybe in NA. In the UK the likely solution would be to install a roundabout. You can’t ignore an upcoming obstacle, in which you’re forced to give way.


Gotta say, as a biker, I love roundabouts for that reason- and people who don't ignore the obstacle go flying [1]. As a driver, I love the idea of drifting around one sometime when I have the skill and there's legitimately nobody nearby. Also forces people to focus, which is nice.

[1] https://duckduckgo.com/?q=car+hitting+roundabout&t=vivaldi


When the real need for a stop is not obvious too many drivers will do a rolling stop anyway.


A rolling stop, dropping to under 5mph, would be quite safe here. The problem is blowing through at a steady and significant speed.


Most UK cities have at least one stop sign, put there so that people doing their driving training or test can have access to one. They really are quite rare.


When 2 objects are on a collision course moving in straight line motion, the heading to the other object does not change.

For this reason, efforts to detect asteroids heading toward earth by detecting their motion against the background sky will fail over short time spans. That's because the ones on an actual collision course will not appear to move against the background for a few days prior to impact. An impactor will seem to come out of nowhere.


The Earth moves in an orbit around the sun, so the only way this would be a problem is if the asteroid were not visible at all until only a few months (or even less?) before impact.


To a first-order approximation, and from far enough away, a collision with the Earth is a collision with the Solar System.

Our motion within the Solar System is relatively small if the asteroid is a very long way away; it's easy to find scenarios where a fast moving asteroid will appear stationary over a 6 month period.


Reminds me of the time I almost died riding on The Embarcadero. This https://www.google.com/maps/place/Embarcadero,+San+Francisco... is the intersection. This is the link to the view you would have as a cyclist https://www.google.com/maps/@37.8051081,-122.4030922,3a,74.5...

Long story short, I was an idiot cyclist thinking I had calculated everything[1], when in fact, I hadn't. Someone in a car going northbound at about 60mph on Sansome had to slam on their brakes to save my life as I crossed from the right bicycle lane to chestnut. I was super lucky they were watching, and their brakes worked, and that they had enough reaction time.

From then on I have never ran stoplights. The problem is that, as they say, the first one is free. You might start out as a cyclist running a simple stop sign on a dead street. But as you get more comfortable, the temptation is to run ever more complex street lights. In my case, I only did it when I didn't see any cars. The problem with intersections like this is there are cars you cannot see.

[1] - Things to calculate:

1. Southeast bound car traffic on Embarcadero.

2. Whether there were southeast bound muni trains on the Embarcadero dividing route.

3. Whether there were northwest bound muni trains on the Embarcadero dividing route.

4. Cars behind you on northeast bound Embarcadero ( I had to cross from the bikelane on the left )

5. Northbound cars on Sansome. This is what I missed.


I don't know who needs to hear this, but the driver who gets mad at you for running a light might be a fellow or former cyclist.

There is nowhere you gotta be that is so important that you should be committing moving violations to get there. The rules of the road apply to you ever bit as much as a car, and you have absolutely no moral authority at all if you won't even follow the goddamned traffic laws.

You are not only risking your own life, you're making the rest of us look bad, and creating hostile drivers that other people have to deal with.


I don't run lights myself, but I don't agree with the theory of perfect symmetry of moving violations. The risk one poses to others by breaking traffic laws is different for a pedestrian, a cyclist, a car, a semi-trailer, and a jumbo jet. Insisting that all violations matter the same is nonsensical.

In places, this recognition has actually been codified into law (see https://en.wikipedia.org/wiki/Idaho_stop).


There's a problem with that. Lots of people who regularly drive cars but never cycle see cyclists flagrantly ignoring the law on a regular basis. It's easy to come to the conclusion that the reason cycling is so dangerous is because cyclists would rather throw themselves into oncoming traffic rather than dealing with the inconvenience of having to stop at stop lights.

And when there are pushes for regulations to make cycling safer, they roll their eyes and vote against it, even when they're simple, effective, cheap measures.

The seemingly widespread belief among cyclists that they don't need to follow the rules of the road is, in my opinion, a large part of the reason Americans are so opposed to changing said rules to make cycling safer. There are a very large number of Americans who believe the primary reason cyclists get hurt is because the cyclist was doing something dangerous.


> Lots of people who regularly drive cars but never cycle see cyclists flagrantly ignoring the law on a regular basis

They also see many more cars flagrantly ignoring the law on a regular basis. On a normal late afternoon, I can stand outside the local supermarket and see 20+ cars jumping red lights, obstructing junctions, sitting on pedestrian crossings, etc. within half an hour.

> cyclists would rather throw themselves into oncoming traffic rather than dealing with the inconvenience of having to stop at stop lights.

Yes, as do a lot of car drivers.


I have seen maybe once or twice in a decade a driver running a red light. I see about 1 in 10 cyclists running a red light. The proportions aren't even close.


I'm not sure that the statistics bear that out: https://beyondthekerb.org.uk/laws-whos-breaking-what/


Ah. Thanks for the data. Now that you mention it, I realize that plenty of drivers run red lights regularly. And yet I very rarely registered it as an emergency situation, especially compared to cyclists. What is going on?!

* Some cyclists blatantly run a red light in the middle of the cycle, oftentimes out of nowhere. Overall, perceived as unpredictable behavior.

* Some drivers tend to run the yellow, and sometimes pass through the intersection a bit after the red has been on. It just happens that the red cycles overlap a bit, then the other drivers are still stopped, and alert for the road to clear. While annoying to lose 500ms of the start, it is fairly predictable and rarely leads to sudden brake slamming.


Whereas in London, for example, I can see probably 80-110% of cyclists running a red light compared to cars on any given day depending where I stand.


My observation of your observations and other observations like it is that the observer chooses a narrow definition of "jumping the lights" that suits their own biases.

Specifically, the issue is with Amber lights. The highway code says:

AMBER means ‘Stop’ at the stop line. You may go on only if the AMBER appears after you have crossed the stop line or are so close to it that to pull up might cause an accident

Observing car driving habits in London, an average of 2-3 cars break this rule every time a light cycles from green to red. This behaviour is legally the same as jumping the light on red. Cyclists are far less likely to break this rule (they're slower across the junction and are aware that that puts them in danger from the other lights going green).

If you factor in all those cars into your assessment, you'll probably find that cyclists are not worse than cars at obeying the law around traffic lights.


I'm going with your definition of "jumping the lights" because that's what I was taught many years ago. I'd also include "people who enter a controlled junction with no clear exit" since they end up beyond the red light without being able to move - that's the situation at our local supermarket.

Normally end up with a bus in the bus lane and 3-4 cars sat in the junction across the pedestrian crossing on every light change at peak time.


> or are so close to it that to pull up might cause an accident

Well there is your loophole big enough to drive a truck (lorry?) through even on an amber light!


Except if you observe a junction for a short while you'll see that in general people drive through even if there is no chance it would cause an accident.

/devils advocate

The loophole for a cyclist is that they could swing their leg off the bike and magically become a pedestrian, cross the stop line, get back on, and legally ride away across the junction regardless of lights. Given that swinging your leg off the bike makes no reasonable difference to anything, why get annoyed if they don't bother with that part?

Isn't it just like claiming a general exemption on all amber lights because doing anything might cause an accident?


I’m not really certain where I stand on that, but several thoughts come to mind.

It’s If a bicyclist and a driver approach a four way stop and the driver runs it, he can kill the bicyclist. If the bicyclist runs it, the driver can kill the bicyclist. While the risk is not symmetrical the outcome is the same.

One would think that the party with more risk would be less likely to run the stop sign but in my experience (which is probably not typical world wide) in the Bay Area the opposite is true. Although admittedly it seems the law just isn’t enforced here. Maybe unequal laws would more likely be enforced and some combination of personal risk plus enforcement would achieve the desired outcome.

Additionally many bicyclists are also drivers. So it might be prudent to penalize them for the behavior equally so that it discourages the behavior in general and removes dangerous drivers more easily; assuming their behavior on different vehicles correlates.


I add another point. All cyclists are also pedestrians. Maybe not in the Bay Area but pedestrians often run traffic lights when there are no approaching vehicles. A cyclist feels closer to a pedestrian than to a driver in my experience. So, no traffic, no danger, run the traffic light. The same cyclist (and pedestria) will stop when driving a car.


As someone who runs red lights from time to time both as a pedestrian and cyclist I more or less think this is the general view, especially if we take into account that bicycle lanes, at least in my country, often are linked to the pedestrian lights. I would never run a light in a car and if I ride my bike on the road I behave as a car.

Another imo. important part of this is the (perceived) risk of running a red light. If I run a red light on my bicycle I yield for everyone, i.e. my speed is low and I only have to watch for cars that go straight through the crossing which are easy to predict. Basically no need to interact with anyone, simply watch out for cars. Following the lights is the opposite, my speed is generally higher and I have to interact with turning cars. All crashes involving cars that I've been in have either been cars that should have yielded when turning or cars that are blowing through stop/yield signs. This is generally how bicyclists get hurt and I mainly see it as an infrastructure issue. The problem is that infrastructure is relatively expensive to change and so the blame often seem to focus on the cyclist for "not following the rules" or "not wearing a helmet" and nothing really seems to change.


Yes, that's it. Actually infrastructure did change in the last 30 years (roundabouts, etc) but to make cars safer, not bicycles. Those improvements were quite successful. Unfortunately they bring cars closer to bicycles any time they narrow the road. Old style intersections like the ones in the article suffer from the constant bearing problem but the cyclist can usually see a car coming from the other road. A car approaching from behind doesn't have to steer toward the side of the road where the cyclist is. With roundabouts and narrow lanes, not much so. Modern roads are also much more dangerous for pro riders. Check how many crashes there are in a bunch because of infrastructure built for cars. That was not the case in the 90s.


If there is no traffic then there is nobody to witness the cyclist, and nobody to get upset about 'bike culture'.


There are also pedestrians in the mix - so a cyclist running a red light can still pose a serious hazard to other people. In the Bay Area there have been cases of pedestrians killed, as well as serious injuries such as broken legs or arms.

I'd also worry about bicycle-vs-bicycle collisions. Maybe density is too low to make this terribly likely, but it doesn't sound like a scenario that would go well either.


Oh wow that's interesting, I live in Washington State and I didn't know that we're getting the Idaho stop in October. It'll be an interesting change...


I do not own a car and cycle every day in SF.

I have seen 3 accidents and maybe 100 near misses involving cyclists and have been in a few myself. In all of them, it was the cyclists fault.

Cyclists may have higher risks, but that doesn't seem to stop us from doing stupid dangerous things all the time. Although in fairness most near accidents I have seen are vagrants crossing a busy intersection without waiting for a green, seemingly with the intention of being run over.


The problem with these threads I find is they end up in anecdotes between cyclists and car drivers. I don't doubt you, I know there are idiots using all modes of transport but from years of cycling in different cities I can counter your points with a lot of my own involving car drivers acting incredibly irresponsibly and dangerously.


When I drive in San Francisco I spend most of my effort watching out for bicyclists and pedestrians. Cars not as much, first they are easier to see. Lower percentage of stupid. Big enough that they tend not to come from unexpected places.

I do that because I want to get out of this life without maiming or killing someone. I'm old enough to know it's long game and to know people that have accidentally killed people. And you don't want to go there. You might think that if it's not your fault it won't fuck with you. Trust me it will.


I used to rationalize it by considering myself a "pedestrian" when I ran red lights while the pedestrian crossing signal was green. Never did it without the crossing signal "cheat" though.

In the end it's the doors that got me, and it wasn't even the parked cars. After that I cut my losses and don't cycle any more.


In my opinion, cyclists should treat red lights like stop signs. Come to a stop, yes, but it's often easy to see if it's safe to proceed. Traffic lights are there to make cars safer. It's completely unfair to slow down cyclists unnecessarily as a result.


The linked road isn't one where cyclists die from running a stop sign, they have right-of-way.


That's a huge intersection, and it sounds like you were crossing instead of just following Embarcadero, that's obviously a terrible idea.


Indeed it was. Even crossing with traffic lights is sometimes a harrowing experience as there are cars behind you that sometimes are going 30-40 mph on that turn.


If anyone's looking to learn more about road layouts (who isn't?!), Road Guy Rob has a good channel:

https://www.youtube.com/channel/UCqdUXv9yQiIhspWPYgp8_XA


Every road is dangerous for a cyclist. Really the only solution is to adopt pedestrian-centric traffic laws like The Netherlands or Japan.

In Japan, blowing a stop sign and killing a cyclist would be a "dangerous driving causing death" charge, which would result in a prison sentence, loss of your license, a fine, and ~$1,000,000 in compensation to the family of the person you hit.


In reality, it doesn't always work quite like this. Japan has a system of assigning a percentage of blame to both parties in a traffic accident. "He was 80% to blame for not yielding, you were 20% to blame for being too far out in the road."

While in general this system works fairly well, there does seem to be a lot of pressure to share blame as much as possible. The only person I know how got 100%/0% was T-boned by a driving going through the middle of a red light.

Also, cars are often judged to be be much more at fault than cycles. Perhaps this is why bicycles can often be very reckless on the roads: taking blind corners without slowing down, cycling on the wrong side of the road against traffic etc.


In reality it does work quite like that if someone dies and you are judged to have driven dangerously (危険運転致死傷罪).


I spent a couple of weeks walking and riding in Japan last year. Tokyo and Osaka specifically. My biggest take away was that everyone is constantly collaborating to make it work. Bikes, people, cars, everyone is shuffling around and compromising. People and bikes seem to slip through eachother when foot traffic is light, with bikes or people giving way depending on what's easier for both. The gutters are often flush with the road, so if there was a bigger group of people a bicycle could just ride off the footpath and back on again to get around them. Half of the time there is no delineation between footpath and road, so cars drive very slowly and infrequently and everyone shuffles around subtly to make it work.

In western cities I've noticed people are instead antagonistic, everyone is actively looking for something to be angry about. If they could help someone by moving a little bit, they won't, because it's their lane not yours.

If you move around stopped traffic to get to a safer spot on your bike, you'll get yelled at, sometimes the argument is that it's "Unfair", like children arguing over who gets the front seat. I feel like it's the car-centric infrastructure that leads people to think the city is for cars.

You don't see this attitude in foot traffic only areas like foot-malls and public transport, where people are seem more likely to help eachother, and you could liken parts of Osaka and Japan to a city-wide foot mall with some allowances for cars.

I also visited Sapporo and whilst there were still lots of bikes it was clear it was a more car focused city, and you could feel how much more difficult it was to move around the city because of it. More time waiting for cars to do their thing before you could do yours, instead of the other way around. So, I'm happy to put the blame squarely on the automobile.


And in America if you want to kill someone the best way to do it is with your car.

https://www.metafilter.com/137440/If-you-want-to-kill-someon...


This is a fascinating look at a perfect storm of a junction. For both vehicles to be unaware of each other just seems unfathomable, especially that this occurs in a place where you’re effectively on an open plain with good visibility in all directions.

I’ve stayed down the road from here (East Boldre) on a number of occasions so I’m familiar with the junction having both driven and cycled through it. I’ve even cycled through there with my kids in a bike trailer, which makes me feel a little sick.

A number of comments are suggesting larger engineering endeavour to fix the issue so it’s probably worth pointing out a few things about the environment, as it’s a fairly unusual place. This is a national park that’s been fairly untouched for a long time. There are a lot of large animals wondering around but rather than being fenced in, they mostly roam freely. They often just have reflective collars to help stop collisions at night where they frequently congregate on the road.

Furthermore, in the Uk in general, intervention seems to be strongly discouraged. Certainly compared to NZ, where I grew up, over here there seems to be more of an expectation that people should do the right thing without being nannied. I was told that when it comes to road intervention, it’s only post incident that changes will be made to prevent future situations from occurring.

Another anecdote. Where I worked in south London there was a junction on a hill where traffic coming down the hill wasn’t allowed to turn across the traffic coming up. There was a sign, but it wasn’t especially obvious. On a weekly basis there was a surveillance van with a camera that sat the fining people (later, through the post) if they broke the no turning rule. We complained to the council a number of times about it because we often saw near misses. It wasn’t until the day a motorbike went through a car windshield that a change was implemented. And, even then, it was only a chance to the signage.


I read this article a while back, and immediately one intersection in my locale came to mind. So on my next trip through it in my car, I took a careful look. Sure enough, my impression was that it would be hard to see a cyclist, or even an approaching car. Of course I'm always careful, but now I'm extra careful.


I'm curious about whether planting trees and bushes would help. This would make drivers know that they haven't seen the other road, and would make them slow down on approach to the junction.


That's not the worst idea, like that they'll take the stop sign serious. In Europe, stop signs can only be installed at certifiably dangerous junctions, but in the current state the intersection doesn't look half as bad as it actually is. With a few strategically placed bushes impressions might actually match on-the-ground facts.


Was doing some charity bike ride when I was 16 and, halfway through, there was something like this. I'd zoned out and was gonna cycle on through the intersection when someone called out for me to stop. If I hadn't, I'd have been splattered by a speeding Corvette. I wonder if this may have played a factor.


As an American I find it very odd that they blame the angles of the roads for making it dangerous. Until recently that intersection had no stop signs. One road had a yield, meaning most of the time no one stops in any direction, on either road. That gets drivers in the habit of not stopping.

Maybe if varies by state, but I grew up in a rural area of California, but every intersection I can remember has had at least one road required to stop (either a two-way stop sign, four-way stop sign, or traffic lights).

I get that stop signs are nearly illegal in the UK and some other parts of Europe, but that is the problem. In the US a driver on the minor road has to stop, look both ways, then proceed. It is to much safer than the driver on the minor road getting in the habit of not stopping and just plowing through a road that has the right of way.


"Plowing through" yield signs is extremely rare and only a common problem when view lines are exceptionally open like in the linked example. Good road design/signing guidelines include those open sight lines in the decision tree, mandating view blockers, swerves or, as the weakest option because people will still ignore it when they feel safe, stop signs where necessary. As a person who learned driving in Europe the American fixation on stop signs seems excessive (particularly the four way).


The problem with stop signs is that cyclists also need to stop and on a bicycle you really notice all the wasted energy.


On this intersection the cyclists that got hit were on the main road, meaning they wouldn't have to stop.

If a cyclist on the minor road had a clear view, slowed down down, and looked both ways, they wouldn't need to come to a complete stop. A cyclist treating a stop sign like a yield sign is pretty only endangering themselves. A motorist plowing through a yield sign that should be a stop sign, or plowing through a stop sign, that is dangerous to other people.


This can be solved with the Idaho Stop (https://en.wikipedia.org/wiki/Idaho_stop), although in they absence of common sense you'd probably need a "really stop" sign for dangerous corners.


Why is the cost to bend one of the roads slightly, creating an offset junction, £100,000?


My guess: purchasing the land, paying for studies, laying new road, removing old road.

£100,000 sounds cheap. Two people already died. If I was a family member of a third victim, I would've wanted the government to pay £100,000. I would be asking government officials if it was worth it.

(Approx 125,000 USD at today's exchange rate)


There's a linked response from Hampshire County Council [1]:

"We are working with partners at New Forest District Council, the National Park Authority, English Nature, The Verderers, The Forestry Commission and the police to explore what can be done longer term and are currently carrying out a review of the junction, which we hope to finalise in the new year. The land beyond the paved road surface is Crown land and this will require permissions to be granted to us for any realignment of the road to be carried out."

Crown land (part of the national park, presumably) means it "belongs" to the queen, so that shouldn't be an issue.

Other comments on that discussion say the same offset junction has been done in many other places.

The best thing is probably for anyone who lives in Hampshire to write to their MP.

https://beyondthekerb.org.uk/collision-course/#addendum


A lot of times where they put in a kink at a junction like that they don't even remove the old road - just leave it and the farmer will use it for storing bales etc.


Did you see this other post on the front page right now?

I Could Do That in a Weekend https://news.ycombinator.com/item?id=23019816


You're linking that just to be insulting, I guess?

Asking why the cost is some number is very different from claiming you could do it yourself for cheaper.

Is the biggest cost tearing up existing things, bringing out the heavy machines, the raw materials, the labor, or something else? How many man-hours are needed anyway? There is nothing wrong with asking why it costs a certain amount. The average person has zero expertise in the cost structure of laying paved road.


Seems really cheap tho. I wonder what the Medical cost + opportunity costs for avoiding e.g. 50% of crashes in the junction would be over e.g. 10 years. Probably a lot more than 100k for fixing the junction.


I think California DOT tracks collisions and has at least some sort of algorithm to decide when to make changes.

Scary looking link to guidelines.

https://fhwaapps.fhwa.dot.gov/hsipp/Attachments/aa343eab-2cb...

That said I looked at the intersection on google maps. Here it would have have had a stop sign at least or fixed decades ago.


I read this article when it was out two years ago, and this is the most important takeaway from it:

> And secondly, significant movement of the head will bring previously obscured sections of road into view.

I've been doing it ever since, always translating and rotating my head quickly on crossings.


Previous (quite lengthy) discussion:

https://news.ycombinator.com/item?id=16112163


I wonder if a “Stop Ahead: XXX Killed at this intersection” sign would be effective. Sure it’s non-standard. But that’s something of a +1 in this situation.


I've often thought it would be useful to put a permanent marker of some sort at the spot of every traffic fatality. In the US, people often put crosses up, but this is haphazard, and of course can't be in the roadway. Maybe a painted gray X or something.

The point is that a crap-ton of these would serve as a useful warning to the wise.


They could install at least two speed humps on approach, one, to disengage the blind spot and a second really large one to force cars to almost stop.


There's no street lighting on this road. You can't use speed bumps in unlit areas (because drivers won't see them at night until it's too late to avoid vehicle damage).


From the article:

>Speed bumps are a reasonable idea in terms of being a low-cost intervention, but regulations permit their use only under street lighting, so they cannot be used here.


Also (adding more detail): The reason why you can't install lights is because there aren't any wires for the electrical grid, so that would cost a lot of money to add, and the locals would likely object to the extra source of light pollution.


I follow him on the why the cars don't see the cyclists. Why don't the cyclists see the cars?


The Tom Scott video has a good animation on this: https://youtu.be/SYeeTvitvFU?t=119

Because of the layout of the junction the cars are actually approaching from behind the cyclists.


Wow: The _very first_ car in that video to arrive at the stop sign fails to stop.

Of the vehicles in the video we see traversing a stop sign, I count 5 cars that come to a stop and 5 that do not. (One bicycle crosses: it comes to a complete stop).


That surprised me.

Stop signs are so rare in the UK -- I can only think of one in the area I grew up -- that they're taken seriously. Or at least, I thought they were.

"Until 2016, each stop sign had to be individually approved by the Secretary of State for Transport.", though that requirement has been removed.


The very first car in _that video_ fails to stop.

You don't know how many times they recorded the intro.

I'm not trying to imply Tom Scott is being dishonest. We just don't know from the video.


Why don't they just add a traffic light?


No electricity in the area and it is a conservation site so digging lines probably wouldn't be possible.


In my country they have these traffic lights with solar cell/battery and a small wind turbine. Seem to work well.


You would just run the power cables under the road. But it would be expensive and cause disruption.


It is the UK. If they were to do anything a roundabout would be more suitable.


Good point, it does look like there's enough room for one too.


I think from the perspective of the cyclist, the car is behind them, and stationary. It isn't in their vision until it's too late, and it won't appear to be moving at all.


Correct - this is explained in the YouTube video linked above [1].

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


The cyclists have right-of-way and have no reason to expect that that cars will simply come out of the side street without stopping, or even slowing down. By the time a cyclist realises it can easily be too late.


I bike 3-4 times a week, but nearly ran over a cyclist myself a week ago.

It was a stop with a right turn only onto a one way street with fairly fast (45 MPH) traffic. A large hedge abutted the sign, making it hard to see more than ten feet of sidewalk.

I looked right as I was pulling up to stop, sidewalk clear. I look left and see it’s clear for just enough to get into tragic. I don’t complete my stop, I’m doing less than 5 MPH and decide to punch it and I hear a scream just as a woman on a bike enters my vision passing right in front of me. She yells at me that she had right of way.

I try to tell her that riding 15 MPH on the sidewalk against traffic requires defensive riding skills. Right of way or not she shouldn’t have ridden in front of me when I was clearly looking the other direction. But before I can finish, another biker going with traffic on the road tells me she’s right and to shut up.

And I do, because I am embarrassed that I did California stop and that contributed to nearly running her over. I was also in the wrong. But people California stop all day long and as a biker I always assume they might.


You were technically in the wrong considering that California stops are never actually legal, but it is extremely reckless to ride at 15mph on the sidewalk, especially if you’re barreling through intersections AND “salmoning” aka riding against the flow of traffic.

If you’re going to ride a bike on the sidewalk you should act like a pedestrian, for everyone’s safety.

If there is a bike lane/acceptable shoulder, you should be riding on that.


Right-of-way doesn't answer why the cyclists can't see the cars.

Right-of-way isn't going to bring someone back to life.


Every time you drive, you aren't hit by cars that simply had a yield sign. You see those cars, and you see them before they have even slowed as they approach the yield sign, and every day you gamble that they are going to yield and let you pass without hitting you.

So, even though the cars are approaching from behind the cyclist, they may see the cars approaching. And just like any right of way situation, they assume the cars will stop. Just like how you don't slow down just because you see someone waiting to go right on red.

Note: the OP intersection has gained stop signs over time to help avoid collisions.


If you're driving defensively, or riding defensively, you can never assume that they've seen you, or that they'll give way.

Difference is when this assumption is proven false in a car, it's generally more survivable than when you're on a bike or motorbike.


Sure, but I doubt you stop at green lights even though someone might run a red light. Next time you drive, notice how many gambles you make despite how defensive you think you are. Hell, a single trip down a 60mph two-way street with only a yellow paint divider has probably exposed you to more risk than all of the mortal danger your defensive driving has saved you. I just think it's a weird line of inquisition to wonder why someone wasn't more defensive when hit by someone else.

Remember, only three cyclists have died at this intersection over the last six years while being a popular bike route. Not every cyclist is getting eliminated here. But it doesn't take many deaths to make you go "hmm, how can we design this intersection better?"

My point is that the answer to "why don't cyclists look to see if a car is running through the yield?" is probably "most of them do". That's why there were only three deaths in six years. It's a weird question to ask because even though you could scold those three people for not driving more defensively, the signage could simply be improved (and it was).


> I just think it's a weird line of inquisition to wonder why someone wasn't more defensive when hit by someone else.

I don't believe I ever asked, or implied, that question.

I'll just add that there's a saying amongst motorcyclists that "there's no point being right if you're dead" - sure, the car _should've_ given way, but they often don't, so you have to ride like everyone will fail to give way, to ensure you have the best chance of survival.


You really can't ride like that though. That would mean slowing down to 10mph at every junction with an arriving car.

You can take steps to be seen - put yourself in a cars sightlines and watch carefully for signs of not slowing down. But ultimately you are moving at a speed which means if someone absolutely guns it out a junction, or changes lanes without looking, you will be hit.

Watching carefully for signs of not being seen reduces the risk, sure. Often to acceptable levels. But it's always there.


Of course, you're absolutely right, it's absolutely impossible to remove all risk, but the only factor in the equation you control is you, so I always try to load the die as much in my favour as I can.


Interesting. So if you are driving on a road and come across an intersection that you don't have a stop sign for but the cross roads do, you treat the intersection as an all-way stop?

In all my decades of driving I have never seen anyone drive that way. I think I'd believe it with dashcam evidence only.


City driving: some drivers have the unpleasant habit of approaching an intersection from a secondary road with no visible slowing down, slamming the brakes at the very last moment. If I happen to glimpse such a vehicle, I hit the brakes myself. Right-of-way won't pay for damage costs.


I watch these intersections closely, yes. And make sure I have time to slam on the brakes if necessary. I've seen far too many cars blow through residential-area 25mph stop signs as if they don't exist, and it really only takes one to give you a very bad day. And that's in residential areas - in higher-speed quieter-area intersections like this, hell yes I'm extra paranoid. I've seen multiple cars plow through intersections like this at triple the speed limit since I started driving.

As a biker, this all applies doubly so, because one mistake like this can pretty frequently be fatal. Be paranoid or you risk death, there's no alternative.


I’ll keep vigilant of someone potentially pulling out, and usually prepare to brake (eg foot off accelerator, prepared to hit the brakes). This is also roughly what we learnt in a defensive driving class I took (as part of high school).

(Note also that all-way stops are rare outside of NA; it’s far more common to have roundabouts or clear priority, but you always keep an eye out.)


I don't stop, no, but I do slow if needed to give myself options.


You should definitely slow enough to look both ways before crossing.

Better than driving ten over and assuming everyone can see every stop sign.


I make sure they start slowing down, or else I'll slow down. I've been cut off by people who did not have the right of way and still took it.

If I gamble like you're saying, I would have been in some bad accidents. To prevent that, I just keep an eye on them, take my foot off the accelerate if necessary, lightly apply the brakes if necessary, etc. It's a dance, and it's not hard to avoid.

Edit: I don't cycle, but it's just as applicable to cars. The same blind spot problem is even applicable to planes. If you're a pilot, move your head! (My second paragraph is about some terrible curved highway merges.)


I'll never forget the basic message from my first day of motorcycle training: you can argue about who was right from your hospital bed, or you can take responsibility for your own safety at all times/under all circumstances.


The car is more than 90 degrees of from the bikes line of travel. The cyclist can't see him because he literally can't see the car.


When I biked, I'd get a 270-degree view just from naturally turning my head as I tracked my surroundings. Plus coverage behind from a head-mounted mirror. Highly recommended.


Yeah, but assuming no right-of-way will lead to not having a life of any sort. I can't even imagine living life this way.

Can you imagine that? A Tesla is stopped at a red light just before a pedestrian crossing. The Tesla can go from 0-30 mph before I can cross its width at walking pace. The walk light is on. I have the right-of-way. But considering the Tesla could go from 0-30 mph in the time I could pass it, your suggested course of action is to just wait until a slower-to-accelerate car stops at the intersection?


In these threads it feels like you are not reading what they are saying, or at least reading it in the least charitable way.

Defensive driving simply means to not assume drivers are going to take an action until they give evidence of it.

If a driver is going to stop at an intersection, they will slow down before they get to the intersection. A defensive driver approaching a crossing with other cars approaching will look for evidence that the other cars are slowing down before assuming that they will stop.

If a car is stopped at a pedestrian crossing and a defensive pedestrian is looking to cross, they will look for evidence the car is about to accelerate into the crossing. They don't assume the car will suddenly accelerate for no reason, because there is no evidence that they would! Evidence that they may suddenly accelerate includes things like looking down at their phone, or not looking at pedestrians. If the defensive pedestrian sees that evidence they approach the crossing with caution, ready to take evasive action or not enter the crossing if needed.

Right-of-way tells everyone who has the right of way, it makes the expected behaviour clear. Assuming that everyone else will do what you expect them to do is extremely dangerous, as even without malice or carelessness it's very easy for each invloved party to have different assumptions about the expected bahviour.

So, to be defensive it's important to

- have a well informed understanding of what you think should happen

- look for evidence that all parties are acting in accordance with what you think should happen

- be prepared to change your actions if any party does not act in accordance with what you think should happen


I think it's quite clear. These threads mostly involve people acting like they're better drivers than they are and claiming behaviour they do not practise. Then they'll come here and act a bit sanctimonious "Why didn't the X just do Y? I always do Y". It's just the Wobegon Effect in action.

I don't read it charitably because of the sanctimony involved in not reading an accident situation with the Understanding Human Error strategy, thereby leading to a bunch of low-quality comments about how people should just be better, involving poor understanding of public health and traffic engineering principles.

It's true, I probably shouldn't engage when the nth accident analysis by a HNer is "Why didn't the pilot just not crash into the mountain? When I see a mountain I just avoid crashing into it". No one is likely to get anything from that.


It's plain hindsight. Everything becomes obvious after you have had enough time to analyze the situation.


I can imagine it because I do. I always keep an eye on cars as I'm walking in their path. It's not hard. I don't stop unless they aren't slowing down, and I'm always ready to move in a different direction and/or a different speed.

I'm not saying everyone can do that, and I think we agree that people shouldn't have to do that. Situational awareness, constantly coming up with alternative plans, and always making sure an "out" is available has kept me alive in dangerous situations. Anyway, that's how I live. People are wired diferently.


All right, describe your behaviour under these (very common, in San Francisco) circumstances:

A Tesla is stopped at a red light just before a pedestrian crossing. The Tesla can go from 0-30 mph before you can cross its width at walking pace. The walk light is on. You have the right-of-way.


What are you trying to accomplish?

To answer your question, it's like I said: situational awareness. Is the driver only looking at oncoming traffic, or do they look around? It's rare, but I have waited at crosswalks with the walk light on because it wasn't safe. I have also walked out of the way or not walked when a driver still saw me and went anyway.


To detect the boundaries of your rules to determine whether they can be implemented reasonably by an arbitrary individual and to illustrate that there are limits where your own stated rules would fail and you likely violate them. So far I have determined from your rules that you should never step in front of an electric vehicle under any condition. The driver could look right at you and accidentally step on the pedal.

After all, situational awareness doesn't bring people back to life.


> I have determined from your rules that you should never step in front of an electric vehicle under any condition.

That would be a poor deduction.

It seems like you have a bone to pick. I don't care to facilitate or engage in such behaviors.


I do regularly make eye contact before crossing in front of cars, even in the crosswalk with the right of way.

But, yes, a car with that much acceleration has no business on the public roadways.


If the Tesla driver does not make eye contact with you, be cautious. That’s defensive walking in a nutshell.


The examples given were cars that failed to yield way when legally required. Operators of heavy, high-velocity machinery should do so responsibly or not at all.


That is explained by this sentence.

A car which is on a collision course at Ipley Cross with a cyclist who is obscured from the driver’s view by the front pillar will approach the cyclist from behind.

So if the cyclist doesn't do a shoulder check, the cyclist won't see it. If they do do a shoulder check, the car will appear to be stationary to them. (It is surprisingly harder to see an object with no apparent motion.)


Presumably they do see them and just assume that they will yield. However legal that might be, it's quite foolish as a practical matter.(source: many years of bicycling) To stay alive, you have to start with the assumption that cars and trucks simply can't see you.

I loved the visual presentation of the problem, but it's hard to fathom the objection to "stop" signs as a solution. At least here in the US, I regard every four-way intersection that doesn't have stop signs or lights as inherently dangerous (and I do indeed slow way down when encountering one).

Had a friend once from a Middle Eastern country, and he described their protocol thus: When two drivers approach a four-way at right angles, they look at each other. The one that looks away first has the right of way. :-(


I have an idea. What about putting a solar powered radar that lights up a flashing sign when cross traffic is detected to draw the driver's attention. Even better would be coupled with signalling that indicates which direction a vehicle is approaching from. Even more advanced would be to compare the vehicle speeds from both roads, and change the warning from yellow to red flashing lights if a collision is immanent.

Actually, I'd like to see that last part put into place at any hazardous intersection, in case a driver misses seeing a stop sign or red light.


Generally one would prefer safety features to be fail-safe, not fail-deadly, i.e. traffic lights that give you green when there is no cross-traffic is OK, but warning only if something is detected is used only in limited circumstances.


This is in the Tom Scott video, but in the case of this intersection there is a combination of conservation area limitations, light-pollution concerns, and a complete lack of electricity.


The author dismisses the question of why the cyclist shouldn't check the cross traffic by implying it's onerous or unexpected to do so becauseof the angle. IMO this intersections real problem has little to do with visibility acronyms and everything to do with simply two roads intersecting with nothing to adjudicate the intersection. I bet $100 the are even more car-car crashes here than car-bike crashes.




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