Junction design in the Netherlands

נשלח 29 במרץ 2014, 12:51 על ידי Sustainability Org   [ עודכן 29 במרץ 2014, 12:52 ]
Source: Mark Wagenbuur, NL Cycling

Part |

State of the Art Bikeway Design, or is it?

An association of transportation experts of 15 major US cities (NACTO) recently published new guidelines for bicycle infrastructure. They claim they are ‘innovative’ and ‘state of the art’ and based on ‘an extensive survey of expert knowledge, [and] existing guidelines from countries and cities around the world’. Some US planners do indeed visit the Netherlands to look at Dutch cycling infrastructure but looking at the new NACTO guidelines we doubt they have too. Just focusing at track widths we read on the NACTO website: “desired width for a cycle track should be 5 feet. In areas with high bicyclist volumes or uphill sections, the desired width should be 7 feet”. This is actually very narrow, 5′ = 1.5 m and 7′ = 2.1 m. The standard width for one way cycle paths in the Netherlands is a minimum of 2.5 m ( 8′). Wider ones are not uncommon. For bidirectional use the minimum is 3.5 m (11 ‘), but most modern cycle paths are 4 m (13 ‘) or more. Although Dutch sources like CROW are quoted as references the Dutch standards were certainly not adopted. The biggest problems with these guidelines lie in the intersection designs. For instance, NACTO states “typical international best practice is a two-stage turn”. We couldn’t disagree more! The shown queuing boxes are a terrible solution. They not only slow cyclists down but put them in a very dangerous position in the middle of the junction where cyclists have to wait while motorized traffic passes on all sides. This is something that you will never see implemented in the Netherlands!

NACTO bike lane / turn lane design

NACTO bike lane / turn lane design

The advised construction of ‘bike lane / turn lane’ is a way to maximize conflict between cyclists going straight on and drivers turning right. Again, this is something you very rarely see in the Netherlands. This type of design was tried, tested and deemed undesirable. The Dutch stopped building lanes like that a long time ago. A few do still exist (I know just one remaining junction approach like that in Utrecht) but they are phased out as soon as possible. Junctions like that seem more usual in Denmark. So what then is the Dutch solution for the junction approach? Where is a Dutch cyclist positioned on a junction and how do the Dutch create a safe left turn? The Dutch standard junction design solves all those issues at once. So you can ask: would this solution at all be possible in other countries? We believe it is and with the help of the NACTO drawings including their advised widths of car turn lanes we were able to create an animation of a Dutch style junction in the US situation.


If anything, this animation makes clear the space is there! But what’s far more important: this type of junction eliminates conflict in turning and crossing movements far better than the advised solutions. So we question where NACTO looked for this “European best practice” which is actually nothing at all like what is implemented in any city in the Netherlands.

Standard Dutch turning lane / bike lane design

Standard Dutch turning lane / bike lane design

However, of course “Europe” is not one place, and to talk of copying “Europe” is rather meaningless. No other country has the same standards as the Netherlands does, nor does any other country have the same participation in cycling that the Netherlands does. As David would tell you: “copying ‘best practice’ from the UK, for instance, would get you no-where at all”.

Later update
It has become clear that because details of the timing of traffic lights were omitted in the above post, some aspects of this design are causing confusion to some readers. With this design:
  • Cyclists can always turn right on a red traffic light, and are protected from any interference from motorists as they do so. Motorists cannot make a right turn on red. Each cycle path is a minimum of 2.5 m wide, and conventionally they will expand in width at busy junctions, so there is space for cyclists to pass each other to make the maneuver.
  • With or without cycling infrastructure, Dutch traffic lights avoid conflict in a way that those in other countries do not. Many traffic lights at a cross-roads in the UK and USA simply have two states. i.e. N->S and S->N are green simultaneously while W->E and E->W are red and vice-versa. Drivers can go straight on, left or right and those approaching in opposite directions will have to cross each others’ paths. However, in the Netherlands it is normal for the turns to have their own traffic lights which have different timings so that conflict is avoided.
  • Synchronization with cycle path traffic lights works in the same way, maximizing throughput while keeping danger at bay. When motorists have a green light for going straight ahead, cyclists also can ride straight ahead without right or left turning motorists having permission to cross their paths. However, when motorists are given a green light for a right turn this is separated in time from the cyclists’ straight on green so that conflict is avoided.
  • You may sometimes have to wait twice to make a left turn. However, you don’t have to wait at all to make a right turn. On average, this cancels out and cyclists are not disadvantaged.
  • At the other popular design of crossing, with simultaneous greens for cyclists, you still can make a right turn at any time, and only ever have to wait once to make a left turn. Cyclists then have an advantage over drivers.

In general, the timing of traffic lights does not disadvantage cyclists on the cycle path. In fact, in some instances, cyclists get a green light twice as frequently as drivers do. This is only possible to do if the modes are separated and have their own traffic lights.

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Picture update 18 April 2013; Photos of junctions that were designed following the principles explained in the video.

To answer questions about the details that have to do with crossing the extra traffic islands that emerge from this design for people with disabilities I have taken some pictures that explain this far better than words could.

Dutch junction design

Traffic light controlled junction with separated cycle path and dropped curbs for pedestrians.

Dutch junction design

Very large junction with separated carriage ways. Two way cycle path with traffic lights to cross the carriage ways. The pedestrians can cross separated from cyclists. There are dropped curbs which are easily passed even in a wheel chair or mobility scooter and the ribbed tiles and dotted tiles give tactile feedback to people with poor vision to safely cross this junction. The lights also give an audible signal to indicate stop or go. (ticks in different rhythms).

Dutch junction design

A junction between a minor and a major road. The minor road is to the right. The cycle path crosses this road uninterrupted, signalling the cycle path has priority. The triangles pointing in the direction of crossing traffic also indicate that. There will also be yield signs outside the picture to also indicate this. The pedestrian area (grey concrete tiles) has a level crossing. Where the street starts there are white tiles with ribs and dots to give tactile information of where the crossing starts and ends to people with limited vision. Where the car is there is a crossing to the left hand side of this picture. If the cyclists in the picture would want to turn left, they would do so crossing the street there. This design, together with the relatively low amount of traffic, makes that traffic lights are not needed here to guide traffic. Even though this is a major road that gives access to a neighbourhood. Cars turning right from the main carriage way into the street to the right have space to stop for cyclists going straight (who have priority) without blocking the main carriage way.

Dutch junction design

Detail of a roundabout with separated cycle infrastructure and a crossing for pedestrians. The curb from side walk to the level of the separated cycle track in red asphalt has a slope so people in wheel chairs, mobility scooters or with baby carriages can easily cross the area for cyclists. The traffic island that separates the cycle track from the main carriage ways has a lowered area for pedestrians to cross it. No curbs need to be taken. The while tiles with ribs and dots give tactile information to people with limited vision. The tiles guide them to the other side of the road. The zebra crossing is slightly raised so motor traffic needs to slow down to pass this zebra crossing. In the extreme left of this picture the circular cycle path is just visible. It goes all around the roundabout (which is not visible).

Dutch junction design

Detail of a T-junction with separated cycling infrastructure. (The crossing of the top of the T on one side.) All the curbs between the pedestrian areas and the areas for cyclists (red asphalt) and motor traffic (black asphalt) are dropped so they can be easily passed in a wheel chair, a mobility scooter or by people pushing a baby carriage.

Dutch junction design

Junction crossing for pedestrians and cyclists of a dual carriage way (2×1 lane). The grey area is for pedestrians.The smooth red asphalt is for cycling and the black asphalt is the domain of motor traffic. For visually impaired the white tiles give tactile information in the form of ribs and dots to where they can safely cross. The curbs are dropped for better access for people using wheel chairs, mobility scooters or prams (baby carriages). There are no lights at this particular junction.

Source: bicycledutch.wordpress.com


Part ||

State of the Art Bikeway Design – A further look

See also the 2014 post that sums up Dutch Junction Design

Last month I wrote about the new NACTO designs for cycle infrastructure and held the junction design against Dutch junction design. The video that went with the post was taken out of the context of this blog and discussed on forums and other blogs. Without the context some people completely misunderstood it.

Right: Dutch design of an actual junction with cycle paths in red. Left: the same ideas used on an American road to see if it could be done.

Right: Dutch design of an actual junction with cycle paths in red. Left: the same ideas used on an American road to see if it could be done.

There were of course comments that you can’t really take seriously: “Yuck. That seems like a parody of over-engineering.” And if someone dares to criticize anything American there is always this: “could be some anti-American bias there.” Other comments were more serious but reveal a completely different frame of reference: “I’m not convinced about the safety aspect. I think that this video exaggerates the danger of crossing at a narrow angle. It’s just a lane change.”‘Just a lane change’? That is an interesting way of seeing it. Indeed the whole object of this design is to eliminate just that action. Because a lane change IS a dangerous thing to have to do. Some commenters were concerned about the remaining space for motorized traffic.

  • “large vehicles are to move closer to the center of the junction, possibly disturbing traffic flow”
  • [there] “appears to be a sharper turning radius for the Dutch motorist”

The radius is the same as for the conventional US junction. But yes, it appears to be sharper, thus making traffic go slower. One more advantage. Others were not convinced about the advantages this design has for cyclists. Summarized they:

  • believe the ‘swerve’ to the right and then to the left is slowing the cyclists that want to go straight on down;
  • fear there would be conflict between cyclists going straight on and right turning motorized traffic;
  • fear they would have to wait twice (and long) to make a left turn.

One person on a forum asked if there were Dutch people who have experience with this type of design who could give their view. Others too seem to think this is new and experimental design that should be tested. Well it was… for about 50 years now. Almost all junctions in the Netherlands with separate cycle paths were built exactly like the schematic design in the first video.

Further explanation


This second video shows the design ‘in action’. A number of Dutch junctions showing a number of situations that perhaps shed some light on all the questions. Now you can also see how the various green phases work. Not only do cyclists and pedestrians have their own green phase. Left-turning motorized vehicles get a separate green light as well, when vehicles going straight on -on the same road- have a red light. While this may seem like a bad idea because you would have to wait longer for your own green light, it is in fact the reason for very fast movements on the junctions. Once you get green you can proceed without any waiting for other traffic users that might be crossing your path as is usual in other countries.

More modern solutions

It is interesting that while other people question whether this design could work the Dutch actually have moved on to more modern solutions. The ‘simultaneous green for all directions’ David Hembrow shows in one of his videos is one more modern approach. But an even more radical change is that a lot of the junctions are being transformed into roundabouts. It turns out that these can handle more traffic in a quicker and safer way without even needing traffic lights.

This is still a cross-roads junction in Google Earth...

This is still a cross-roads junction in Google Earth…

modern roundabout

…but it was already transformed into a more modern roundabout as can be seen in Google Streetview

So that is the next step the Dutch are taking. I’ll look into roundabouts in more detail in later blog-posts.

There is a video that quite clearly shows the Dutch junction design in real life. In the blog post about riding past red lights.

And there is a 2014 post that sums up Dutch Junction Design.

Source: bicycledutch.wordpress.com



Part |||

Junction design in the Netherlands

One of my most viewed videos is an animation I made in 2011, showing that a common Dutch type of junction design with protected cycle tracks would in principle fit in American streets. To deal with many questions I showed real examples of that particular junction design in a second video. But there were still some unanswered questions that kept coming back and I had therefore planned to make a new follow-up to better explain this type of design. Then Dick van Veen, a Dutch senior city planner and traffic engineer at Mobycon asked me if he could use parts of both my videos for a project earlier this month in Canada. I then decided that the new video had to be made. My own ideas coupled with Dick’s professional expertise led to a new video which he has indeed used in a presentation. I heard it was very well received. I planned to publish a post with this new video on a later date.

junction-design01

A common Dutch junction with protected cycle tracks all around it.

But by sheer coincidence David Hembrow then published a follow-up, in which he states that this design is just one of many possible solutions for a junction and that people shouldn’t just focus on this particular solution alone. Then even more coincidental, my initial video got a lot of renewed attention when Nick Falbo published his interpretation of the design and the way it could be implemented in the US. After these publications a lot was written all over the internet in comments, tweets and forum discussions. Prof. Peter Furth from Boston’s Northeastern University showed me some of the questions he had received directly, with his answers that I fully agreed with. With such a commotion it is high time I publish my own follow-up video with an explaining post. So here we go!

Common Dutch Road Design

There are many questions about the status of this design. How common or standard is it? David Hembrow argues it is not the only solution and it is in fact not the most used solution in the area where he lives. I agree with the response of Prof. Peter Furth to this: “That’s true in smaller cities, which have few major traffic roads and where signalized intersections have been replaced with roundabouts in great numbers. But in larger cities, cycle tracks along the main arteries are routine, as are signalized intersections where such arteries meet. And wherever traffic arteries with cycle tracks meet at a signalized intersection, this is the routine, standard design. You can see scores of them in the Hague, Rotterdam, and Amsterdam.”

It is a fact that in the Dutch situation protected cycle tracks alongside main streets do not stop at junctions, but continue in one form or another on the junction itself, so that such a junction can be traversed by people of all ages and abilities (cycling or walking) in a safe and convenient way.

junction-design03

A still from Nick Falbo’s video shows the space for a car to wait for people cycling and walking out of the way of straight going motor traffic.

junction-design04

A real example of the same situation as portrayed in Nick Falbo’s video shows that he indeed got it right.

Some people misinterpreted the focus on the protective traffic island in the corners. I started with those in the animation because that was an easy way to explain the design. In reality that island is the last thing on a Dutch designer’s mind.

“These traffic islands are not always the same and not even symmetric, they are the result of the tight radius for right turning cars to decrease their speeds on the intersection and the decision to design the cycle track slightly bent away from the intersection”, explains Dick van Veen. “This not only creates a safe waiting place for people cycling, but also a waiting place for exactly one car in that turn. It is right before the crossing place for people walking and cycling, but it is at the same time out-of-the-way from straight going motor traffic. This is a most important fact that is easily overlooked: the location of the stop line for cyclists. Another reason for the bent out cycle path is to make the distance between the carriage way and the cycle path large enough for a wheel chair or a mother with a baby carriage to stand there and wait for a safe crossing moment.” The advantage of this design is threefold: you create a safe place for motor traffic, for people cycling and for people walking.

junction-design02

Left, a sketch by a Dutch road designer reveals that they do not start with the protective traffic island, but with good flowing cycle tracks without tight turns, on which you can cycle at high speed. Right, what a finished design looks like.

junction-design07

This interpretation from Christchurch in New Zealand has not gotten it right. There is too much focus on the corner traffic islands but the stop lines for cycling are in the wrong position. This way there is no protection against left-hooks (right hooks in the rest of world because in New Zealand traffic keeps left). Also, the right turn is impossible to make because you get on the wrong side of the traffic light in the far corner.

junction-design06

This junction proposal for Washington DC has not gotten it quite right either. The turns for people cycling are too tight. Here too, the stop lines are in the wrong position.

The one car length long waiting area in the turn makes that traffic lights can be arranged in a flexible way. In the Dutch situation a straight going cyclist as well as someone crossing the street on foot always have priority over the turning car. So even when the traffic signals are not working the car must wait and has a place to safely do so. When there are traffic signals the best solution is a separate green phase for straight going cyclists and turning cars. “But,” adds Dick van Veen, “no extra phase for cycling is needed. Dutch traffic signals work in a more sophisticated way and an intelligent and complex way of creating signal phases makes it possible that traffic in completely different directions, especially also people cycling, can have green at the same moment together with pedestrians, or cars turning in another direction. The total waiting times for any type of traffic are then almost always under one minute, which is to keep traffic flow high and to discourage red light jumping.”

Further developments

Dutch junction design has developed further and a more modern solution is the Dutch single lane roundabout. Dick van Veen says: “This has been proven to be much safer because first of all a roundabout reduces conflict between motor vehicles. The tight dimensions decrease the speeds and at 20km/h everything becomes much safer. These roundabouts eliminate high-speed right-angle collisions because only head-to-tail collisions at lower speeds can occur. And second, different types of traffic cross each other’s path exactly where the speeds are lowest instead of where they are highest, which is the case on a traditional crossroads. Space is not the issue. A roundabout does not need more space than a crossroads. A circle with a diameter of 15 or 16 metres is already within accepted standards.” That the Dutch roundabout, including the cycle tracks all around it, can be built in almost the same space of a traditional junction is the reason why so many are being converted.

junction-design05

A junction in ‘s-Hertogenbosch NL. Left Google shows the 2009 before situation. Right Bing maps shows the 2012 after situation. From a four arm crossroads to a roundabout in about the same space. Both with protected cycle tracks all around the outside.

There are other developments too. In streets with a maximum speed of 30km/h separated cycling infrastructure is not necessary. Since the Netherlands now has about 35,000 kilometres of streets with such a speed limit we don’t see the design there. What we do see a lot is unbundling of different types of traffic at route level. What mostly happens is that through motor traffic gets a new detour around a certain area and the original direct routes with a substantially decreased volume of motor traffic can then be changed into a through route for cycling. Possibly as fietsstraat (a cycle street where motor traffic is not allowed to overtake people cycling). Such cycle routes then only cross main motor traffic routes at fewer places. This makes the construction of grade separated solutions feasible in terms of cost and space needed.

Good solution for (signalised) junctions

So there is an array of measures from which Dutch road designers can choose what is best for a particular situation. But in busy and older down town areas in larger cities there is often no space for the more elaborate measures with detours and tunnels or overpasses. And although even there we see an increasing number of roundabouts, this type of junction design – a crossroads with cycle paths around it, most often signalised – will remain the safest solution for a lot of places in the Netherlands.

Since many cities in the world have such signalised junctions, this solution to make cycling safer might work there too. So it is great to see a good interpretation like the one Nick Falbo has made.


Source: bicycledutch.wordpress.com

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