Thursday, 16 July 2015

Notes on a City. How problems which could be seen 40 years ago have not been solved and how an obvious solution was overlooked

In this blog post I highlight problems in Wellington, New Zealand. Please don't turn away just because you don't live in Wellington because many cities across the world have exactly the same struggles to cope with the volumes of traffic. You may well recognise the problems that Wellington faced and is facing as being similar to those of your own city.

A few days ago I came across a very interesting 44 year old film about the problems caused by mass motoring. Participants in the film talked about planning to avoid future problems. The film was made in Wellington, New Zealand so this blog post is in large part about Wellington. But actually, the film could have been made almost anywhere because the problems which it presents and the suggested solutions are common to almost anywhere. This film could even have been made in a Dutch city at that time as Dutch cities faced very similar problems.

But first of all, let's remind ourselves of what many cities around the world look like now:


Wellington New Zealand  - February 2015

Now lets look at the 44 year old film which shows what many cities in the world looked like in the early 1970s. I recommend watching it all eventually, but it is quite long. Perhaps watch the first minute now and then return after reading  the blog post:

Wellington New Zealand - 1971

Traffic jam in 1971. What's changed ?
One of the comments under the youtube video says "40 plus years on we still have the same unresolved problems...", which is of course a problem common to many cities across the world.

Planner trying to work out how to
resolve traffic problems between
Wellington, Hutt Valley and Porirua
What makes the film particularly interesting to me is that it doesn't only show the problems, but that expert and sensible people have thought about the problems and make suggestions of ways to try to resolve some of them. However what absolutely no-one in the video ever does is suggest that non-motorized transport in the form of bicycles could be any part at all of the solution.

I suspect that many Wellingtonians believe, just like people all across the world, that their city is not one in which bicycles could be practical. There will be people who think that Wellington's hills, wind and rain make cycling impractical. These are common myths. However cycling in Wellington most certainly is possible for average people for at least some of their journeys and the film provides evidence that this is true: While no-one ever talks about bicycles in this film, and the focus of the film is certainly not to demonstrate that cycling is possible in Wellington, the film-makers couldn't help but include bicycles ridden by Wellingtonians in their film.

People rode practical everyday bicycles in Wellington in 1971. Upright position, three speed hub gearing, mudguards, carrier.
The people who we see cycling in Wellington in 1971 are not sport cyclists. They are going about their everyday life using a bicycle as a practical way of getting about. These bicycles are suitable for socializing, for shopping trips, for going to work, for going to school, for carrying children.

Some politicians in New Zealand may not remember that cycling was once relatively normal, but I do.
This shot of a supermarket showed cyclists, pedestrians and drivers as visiting for their shopping. Of course, if you plan only for motor vehicles, motor vehicles are what you will end up with.
When the camera showed busy roads like this, hostile to cycling, no bicycles were caught on film. As roads become busier, most people will cycle less or stop cycling altogether.
An aspirational picture of a new suburb includes a bicycle, but it is not spoken about.
In a real suburb of Wellington there is no comfortable cycling infrastructure. This leads to cyclists being under pressure. Cycling on the pavement is a symptom of that pressure
Pedestrianization: Streets which once accommodated all traffic are transformed so that they don't accommodate any. This can result in making good conditions for people who visit by motor vehicle and use the supplied car parking, at the expense of making the destination awkward to use for those who cycle. Pedestrianized areas can be designed to allow and encourage cycling.
New Zealand's cycling decline may have started before
that of the UK but there will have been a time when New-
Zealanders too cycled more than the Dutch do now.
In the photos above you'll see evidence that into the 1970s, New Zealanders still used the same practical everyday bicycles as are seen in the Netherlands these days. You'll also see some of the factors which were already putting pressure on cycling and which eventually would lead to it being something which only hardened "cyclists" would be involved with.

Cycling was once a popular means of transport in New Zealand: "Cycling became a popular mode of transport in many parts of New Zealand for half a century," but "in the 1950s and 60s government transport funding and policies favouring motor vehicles as the transport of the future". The same decline was seen worldwide, including here in the Netherlands. It is only by similar government action to that which made cycling decline that cycling can be made attractive once again.

Unfortunately, cycling was not valued sufficiently in 1971 even to be mentioned by planners in the film.

Making choices
There is an interesting quote at the beginning of the film: "It is an indication of the influence of the motor vehicle, that it makes us take stock of things, even to the extent of asking what sort of lives we want to lead." A choice needed to be made. The film-maker realised that many futures could be planned depending on how people wanted to live.

While the problems caused by mass motoring were already highly visible 44 years ago, a choice was made in most places to continue to favour the motor vehicle. That has not changed over the last four decades, and the problems caused by making that choice are still evident.

In the 1970s, the same policies were being followed everywhere. The Netherlands is no exception. These photos from Assen in the Netherlands in the 1970s are very similar to the photos of Wellington. Assen looks different now because a different decision was made. The result is that the city centre has been transformed so that even small children can ride their bicycles in from the suburbs and enjoy a great degree of freedom when they arrive. The links underneath each photo following show how these places have changed in the last 40 years:

A Dutch supermarket in the 1970s. The car-park is more than full, conditions for cycling were not particularly pleasant. Take a look at how this location has been transformed.
Dutch city centre street in the 1970s. No space was allocated for comfortable cycling and pedestrians had little space. See how this street looks now.
1970s Assen street. Cyclist in the middle of the road waiting for a second transport revolution which would result in a very different street scene

Assen early 1970s: An aspiration shown to encourage bikes in the picture above was reality in this location. This cyclist is entering a newly built suburb using a tunnel which avoids a large traffic light junction. It still exists and is very useful today. Note how this cyclist looks just like those in the old film from Wellington. In the Netherlands, these people continued riding. But there's one important difference. This new suburb, built between 1970 and 1975 and very much part of the solution to the problem, was planned like most Dutch suburbs to be pleasant to live in, low-rise and very spread out compared with the high density type of housing under consideration by participants in the Wellington film.
Facts and questions
Routes followed by commuters
in Wellington are exactly as
discussed in the 1971 film
(source, licence: wikipedia)
Wikipedia has a good page about Wellington. The city has a population of just under 400000 people. Property market speculation pushed up prices so that city centre living is expensive, the result being that "The typical central city apartment dweller was a New Zealand native aged 24 to 35 with a professional job in the downtown area, with household income higher than surrounding areas. Three quarters (73%) walked to work or university, 13% travelled by car, 6% by bus, 2% bicycled (although 31% own bicycles), and did not travel very far since 73% worked or studied in the central city". Note that even in the very centre of the city, and even with a demographic group which is the very easiest to attract to cycling, people are more likely to drive or to take public transport than to ride a bike.

Wellington has a mild climate. Neither summers nor winters reach the temperature extremes of Dutch cities. So we can't blame the weather for the low rate of cycling

Hills are also not an issue in for city centre cyclists. Indeed, the route out to the Hutt Valley is also quite flat, and where there were hills on the way to Porirua a reasonably flat route has been hewn out of rock for the motorway.

Some of the suburbs of Wellington are hilly - comparable with those of Trondheim, where of course the weather is genuinely a challenge in winter yet the aim is to achieve 15% of journeys by bike by 2025.
Read: population density and cycling

The population density of urban Wellington is slightly higher than that of Assen (890 vs. 780 people per square kilometre) while the metropolitan area density is very much higher than that of Trondheim (290 vs. 37 people per square kilometre).

None of these popular justifications for a low cycling modal share would appear to apply to Wellington (nor to many other places) so what is real reason why so few people cycle in the city these days ?

You get what you plan for
Here's my hypothesis about why it is that cycling is still so unpopular in and around Wellington: The city and the surrounding area are treating cycling no more seriously now than they were in 1971.

The same could of course be applied to very many cities around the world. Here are some examples of Wellington cycling infrastructure. The absolute minimum has been done. Would you enjoy cycling in these locations ? Would you encourage your children or your partner, your parents or anyone else that you cared about to cycle in these conditions ?

Near the city centre. Hills are not a problem, but look at the road. It's five lanes wide road with a three lane wide advanced stop box. Only the bravest of cyclists will be able to make use of this to turn right.
On a commuting route: Five lanes for cars and trucks + a pavement for walking on, which you can also cycle on, but watch out for the parked (and parking) cars and the lamp-posts. Not an attractive environment for cycling. The distance from Lower Hutt to Wellington is less than 17 km. It's not at all unusual for Dutch school children to cycle up to 20 km to get to school. Would you want your children to cycle this route ? See it on Google Maps.
Another commuting route: On the right, a cyclist. Fantastic brave human-being riding between a six lane motorway and rock face on a narrow strip of bumpy asphalt. Bigger view here.
Another view, another brave person. Note that the path is not only narrow but it has posts on it which cyclists have to swerve around. This does not make for pleasant or safe cycling.
Alternatives
Many people have uploaded videos of traffic jams in Wellington to Youtube. No-one likes being stuck in a traffic jam, but when planners have concentrated only on driving and provided no real alternative for most people, it doesn't really matter how terrible the experience of driving becomes, people will still find driving to be their least terrible option and so they will still drive.

Still from a video of a 13 km long commute by bike in Wellington. This is a shorter distance than many Dutch children cycle to get to school, but the video maker describes it as "intimidating even for confident bicyclists A 100 km/h multi-lane road with a painted stripe for cycling on the wrong side of the crash barrier is not nearly good enough to enable mass cycling. Please do watch this video and compare it with the conditions faced by drivers. By car it's slow and annoying, but it clearly doesn't feel so dangerous as cycling.
Google Maps suggestions for a similar journey, Wellington to Lower Hutt.
By car: Start now, takes 19 minutes                          
By bus: One bus every 60 minutes, takes 35 minutes
Without a good alternative, people will continue to drive. I like cycling, but like the 29% of people who live in the centre of Wellington who own bikes but don't cycle, if I lived and worked in Wellington or a city like Wellington, then I might well drive instead of cycling. The infrastructure could not be better designed to make this happen.

Conclusion
This blog post has concentrated on Wellington in New Zealand, but because the problems faced by Wellington are exactly the same as those faced by many other cities, the same applies to almost Anytown in almost Anycountry. Policy's just the same.

Until a genuine choice is made to favour something other than the automobile, more and more dependency on motor vehicles is the only likely outcome. Cycling is a very fragile mode of transport. Cyclists are very obviously exposed to danger when they ride on busy roads or on inadequate paths next to roads, and this is why cycling is extremely sensitive to subjective safety issues. It's not realistic to expect that people will take to cycling in any appreciable numbers when the experience of cycling is akin to that of taking part in an extreme sport.

Cycling was once popular in almost every country. Motor vehicle use rose not only due to cars being attractive in and of themselves, but also due to motoring being subsidized by government. This pushed cyclists aside both in plans and literally on the streets leaving those who still cycled in an increasingly precarious position. It took billions in investment and a lot of time for cycling to decline to the point it has reached now. For cycling to recover will also require considerable investment from government as well as time. There is no easily reached "tipping point" beyond which cycling will automatically increase. If such a thing existed then cycling would never have decreased past that point.

In recent years, the Netherlands has led the world in cycling investment. Even here, the government has never spent more than a fraction of the amount on cycling that they spend on roads for cars, but this has been adequate to stem the flow of people away from cycling and to lead to a modest increase, In the Netherlands, the majority of trips and the vast majority of kilometres travelled are by motor vehicle. It would take a lot more than the Dutch have done to change that. However, at least in the Netherlands cycling has been made both accessible to everyone and very safe. No helmets required.

Helmets
Cycle-helmet zealotry in New Zealand has no doubt done harm to cycling by making an already unpopular activity even less attractive. Much of the damage had already been done, in that cycling was already at a low ebb. However, helmets will make it more difficult even to grow cycling again and for that reason I oppose the mandatory wearing of helmets. In any case, any emphasis on helmets is in the wrong place. Successful campaigns to improve safety, especially of children, do not rely on secondary devices such as helmets to mitigate the results of crashes, but remove the source of danger so that crashes do not occur.
A grid of high quality go-everywhere cycle-paths is what keeps these children safe, not helmets. If New Zealand had done the same thing then Aaron Oaten's crash and resultant injury would almost certainly never have happened. Preventing collisions is far more effective than allowing them to occur and trying to prevent the worst injuries with safety equipment.
Compare the following two graphs showing the effect of both New Zealand's bicycle helmet law and the effect of Dutch cycle infrastructure:

Effect of New Zealand bicycle helmet law. ""Of particular concern are children and adolescents who have experienced the greatest increase in the risk of cycling injuries despite a substantial decline in the amount of cycling over the past two decades"

Effect of Dutch policy to make roads safer and build cycle-paths, especially concentrating on child safety. Between 1972 and 2013, fatalities on the roads dropped dramatically. Child road fatalities dropped by 98%.
The successful road safety policy removed the danger from where vulnerable people were. This led to a huge reduction in the number of people either injured or killed. The absolute number of child fatalities dropped by 98% over a period of time when the population size and the proportion of trips made by bicycle both rose significantly.

Monday, 6 July 2015

A "Pinch-Point" design which slows cars without "pinching" bikes

On-road cycle-lane approaching a pinch-point. A potentially dangerous situation for cyclists. Note how from this view the driving lanes appears to narrow at the pinch-point.
Pinch points are often installed on roads to slow motor vehicles and to provide crossing places for pedestrians. They are often dangerous for cyclists. Road lanes which suddenly narrowed to encourage drivers to slow down can force them to come too close to cyclists resulting in close and dangerous overtaking or even a collision. However pinch-points do not have to be built in this way. In this blog post I illustrate a "pinch point" which doesn't really pinch at all. While the pinch-point appears from a distance to restrict the space for cars, resulting in drivers slowing down at the junction, the driving lane actually widens through the pinch point. The cycle-lane has constant width.

Thorbeckelaan from ground level
Thorbeckelaan has a 50 km/h speed limit. These photos were both taken while riding along the road from west to east.
Before the pinch-point. The driving lane is 2.8 metres wide, the cycle-lane 2.1 m wide. Note reasonably wide parking bays and a 0.5 m wide drain. The width of the drain helps to reduce dooring incidents (explained here), as does this being relatively infrequently moving residential parking and not business parking.
At the pinch-point, the cycle-lane remains the same width while the driving lane increases to 3.5 m in width. This still causes drivers to slow down. The narrowing of the driving lane back to 2.8 metres is visible after the central reservation. At this point there is of course no space for car parking.

From the air
Aerial photos (from Google Maps and Ongelukken Kaart) provide another view of the same cycle and driving lanes. The photos above were taken facing east (i.e. view is from left to right on the photos below):



On-road cycle-lanes - not really a good idea
This blog post highlights a good example of how a pinch-point can be built which successfully reserves space for pedestrians crossing the road and also slows drivers, without squeezing cyclists. It's certainly an improvement over other pinch-points I've seen where cyclists are squeezed by drivers as they pass through pinch-points. However I don't mean to suggest that this road layout, with an on-road cycle-lane, is actually particularly good. Such infrastructure shouldn't be an aspiration.

On-road cycle-lanes are well known to cause a myriad of problems for cyclists worldwide, but context is always important. This arrangement works fairly well on this road because cyclists travelling west-east along this particular road are protected from conflict by several other factors which are specific to the character of this road:
  1. There are few destinations on this road so few clashes with drivers starting and stopping.
  2. Residential side streets do not provide through routes by car and therefore few cars turn into or out of the side roads.
  3. There are no bus-stops along this road.
  4. The cycle-lane is of a good width, providing wiggle room.
  5. The parking along the road is for residents, so those cars rarely move and the drain provides a gap where there are parked cars, reducing the risk of dooring.
Because of these factors, almost all motor traffic on this road travels all the way from one end to the other without stopping and there are few conflicts caused by drivers cutting across the cycle-lane. Note that both ends of this road have extremely safe junctions. At one end there is a very safe roundabout and the other has a very safe traffic light junction. Neither of those relatively large junctions have ever caused cyclist injury.

In other locations the problems would be greater. That is the reason why this layout is by no means a substitute for proper cycle-paths. Though it is overall quite well designed, this road (when riding west to east) is still one of the least pleasant along which to cycle within Assen. In particular, being overtaken by a bus or truck while riding side by side in the cycle-lane is not especially pleasant.

On the other side of the road there's a segregated cycle-path.
A video shows the popularity of the sports club on that side
The other side of the road
This road is unusual in that while there is an on-road lane for cyclists heading from west to east, cyclists heading in the east-west direction are provided with a kerb separated cycle-path on the other side of the road. The cycle-path not only feels far safer but due to being 2.5 metres wide and having a 0.5 metre buffer, it provides more space for cyclists further from motor vehicles.

On this side of the road, there is little or no discomfort due to being passed by a large vehicle.

Note that with a proper separate cycle-path, pinch-points have no effect whatsoever on cyclists so can be made quite narrow in order to reduce the speed of motor vehicles. However on this road the driving lane widens on both sides through the pinch-point.

Read about other examples of pinch points with cycle-paths and at village entrances.

This junction doesn't have a good safety record. Why ?
This road is a busy west-east route for both bicycles and motor vehicles. On its length there are three pinch points of a very similar design to that emphasized here. Two of these pinch points have a good safety record while this one has a relatively bad record by the standards of Assen. Why ? The reason is that this pinch point also happens to be a junction with a busy main cycle-route north-south which provides access from some suburban areas in the North to the city centre.

The red flag with "10" within it on the second aerial photograph tell us that this junction has seen ten incidents since 2007, four of which caused injuries to cyclists, one of which injured a moped rider and one of which caused the unfortunate death in 2009 of a 76 year old female moped rider, in collision with a large car.

A cropped version of the first photo in this blog post. Does
each participant in this scene know what the others are doing?
The most common recorded cause of crashes at this location is "no priority given". This suggests that people find it difficult to see each other well while maneuvering or find it difficult to judge whether they have time to complete a maneuvre. Turning across traffic from an on-road cycle-lane is always difficult because the cyclist's proximity to the driving lane results in having limited rear visibility. 180 degree head swiveling is required to see behind, which complicates control of the bicycle and makes correct decisions more difficult to make. The lack of gap between the cycle infrastructure and road also makes it more difficult for drivers to predict cyclist behaviour. Could you tell at a glance what everyone in the photo beside this paragraph was about to do ?

It has been known for many years that unsignalled crossings are far more dangerous than either well designed roundabouts or well designed traffic light junctions. Therefore it should not be surprising to us that the well designed junctions at both ends of this road (both of which are illustrated at the links in the previous sentence) have a far better safety record than this relatively minor junction half way along this road.

Due to the designed higher speed of this road (speed limit 50 km/h), the heavier traffic at this location and limited sight-lines compared with motor vehicle speed, this is not a suitable location for a cycle priority crossing like those which I looked at a few weeks ago.

How not to build a pinch-point
Pinch points which cause problems for cyclists are far more common than those which do not. Here are two examples which featured regularly on my commutes in Cambridge:

Don't copy this: Several narrow pinch points exist on the narrow but busy trunk road which passes through Harston in Cambridgeshire. Cyclists have no good alternative to using this road. Drivers habitually exceed the speed limit here, especially at the ends of the village where the speed limit drops sharply from 60 mph to 30 mph. I estimate the width of the road through this pinch point to be around 3 m. No additional space is provided for cycling. Note also dangerous steel railings which cyclists can be pushed against and that the paint pattern used in the middle of the road through almost the entire village also encourages drivers to give as little space as possible when overtaking cyclists.
Don't copy this: When the new development of Orchard Park was built in Cambridge, the re-design of roads near the development brought many new dangers for cyclists. Several crossings and other features were added to Kings Hedges Road and they were nearly all built with pinch points in widths known to encourage close passes by drivers. Orchard Park could have been built similarly to new Dutch developments. e.g. Kloosterveen
Both of the examples of pinch-points above increase danger to cyclists. They reserve no separate space for cyclists at all and they encourage bad overtaking behaviour by drivers, especially those who misjudge the speed of a cyclist and believe they have more time to overtake than in actually the case.

But it's not only in other countries that mistakes have been made. We don't have to look very far from home in the Netherlands to find bad examples from this country. For example, we also have these examples near the centre of Groningen and in a residential area in Assen:
Don't copy this: This very poor pinch-point in Groningen demonstrates nearly the opposite of what is shown in the good example above. The road lane decreases from 3.5 m to 2.8 m through the pinch point while the cycle-lane is an inadequate 1.2 m the whole time. This leaves a width which encourages close overtakes - e.g. by that bus. Just because something exists in the Netherlands, that doesn't mean it's a good example
Copy this only with caution: This is a residential street in Assen which has a relatively minor speeding and through traffic problem. These planters create a different type of pinch-point, potentially causing conflict between cyclists and drivers heading in both directions. Even when the same idea is used with a cycle bypass there is still potential for danger.
Just because something exists in the Netherlands, that doesn't mean it's a good example. Context is always important and ideas which may work well enough in one street in the Netherlands cannot necessarily be translated to a different place and work well there too. Older examples like this are perhaps more understandably sometimes of poor design, but there are also examples of less well thought through brand new infrastructure which work poorly.

Not enough space ?
One of many very narrow streets in
Assen which didn't have enough space
for a pinch-point or for motor vehicles
either. Assen moved the through
motor traffic
elsewhere.
I predict that some peoples' response will be there is not enough space in a given location for a safe pinch point to be built. This may be true for some locations, but if it is true then I would contend that before considering building a dangerous design of pinch point you should think very carefully about whether any pinch point at all is appropriate in that location.

Other ways of removing conflict are possible. For instance, moving motor vehicles onto completely different routes. This has resulted in many minor streets and roads in the Netherlands working extremely well for cyclists and pedestrians without the need for pinch points or other obvious physical infrastructure.

Learn more by seeing the real thing
Book now
We offer the only independent study tours of Dutch cycling infrastructure with a native English speaking guide to minimise the chance of "lost in translation" errors. On our study tours we take care to demonstrate not only many good examples of good infrastructure but also explain why the less good examples should not be emulated.

Monday, 29 June 2015

Study Tour round-up (June 2015 with Cambridge Cycling Campaign)

Study Tour participants from Cambridge riding on a canal-side cycle-path in Assen.
Our study tours in Assen and Groningen have been quite popular this year. The feedback section of the study tour website shows where most of the people have visited from and there are plans for more visitors. The photos below show some of what we currently demonstrate on study tours:

This photo may not appear to have much connection with cycling, but the top of this hill gives me a chance to illustrate how unraveling of cycling routes from driving routes creates excellent conditions for cycling.

While our bikes waited at the bottom of the hill, they were passed by a stream of cyclists. The intensity of this stream varies (more at rush hour) but true mass cycling means that there is almost always someone in sight on a bike, even at quiet times of the day.

Wide cycle-paths, separating people from motorized traffic as here emerging from a bicycle tunnel ,result in conditions where smiling is normal while riding a bike.

Room to spread out without getting in anyone's way.

Explaining and demonstrating how even residential streets which are very close to main roads are not affected by the noise of traffic, reducing everyone's stress and fostering good relationships between neighbours.

Cycle-parking for bus passengers and a bus-stop by-pass which is virtually invisible to cyclists. Note that the 3.8 m wide cycle-path is designed to facilitate efficient cycling and therefore does not narrow as it passes the bus-stop.

Assen city centre. Demonstrating a junction which used to have traffic lights to deal with high volumes of motorized traffic now no longer needs them because the centre no longer has through motorized traffic. See a photo of how this used to be.

The school run in Assen. Children ride their own bikes and have a great degree of freedom. Dutch children are recognized by UNICEF as having the best well-being in the world.
Indoor cycle-parking at a new primary school.
Not just pretty pictures
Pretty pictures do not make cycling normal. In order to make cycling attractive to everyone the infrastructure has to be designed such that it invites people to cycle. Cycling has to be efficient and convenient and also very safe (most importantly: very subjectively safe).

Therefore, as well as the more photogenic subjects, we also took a close look at in such things as the following:
  1. The safest roundabout design for cyclists. Design details are very important.
  2. The safest and most efficient traffic light design for cyclists as well as the quite different design used for most larger junctions.
  3. Traffic lights which default to green for cyclists
  4. Town centre from which through traffic has been removed
  5. Residential streets providing plenty of car parking spaces but on which moving cars are rare.
  6. Direct convenient and safe cycling routes to Assen city centre from suburbs, villages and even other cities.
A city which demonstrates much good practice
Everyone can reach everywhere in Assen by bicycle. Rather than being carried on parents' bicycles, even small children routinely ride to the city centre on their own bikes using the same well-designed fine grid of high quality cycle routes as everyone else uses, regardless of age or ability.

Why isn't everywhere like this ? All cities could plan in the same way. We can show you, your politicians and your planners what has been achieved and how it affects everyday life. Everyone stands to benefit from better living conditions. Even determined drivers benefit from better cycling infrastructure.

More information
More information, including video, is available on the study tour website.

Our next open tour is at the start of September. You can reserve a place on that tour now (private tours are also available).
Book a place on the next tour

Friday, 12 June 2015

The Slow-Turbo Roundabout. A promising new Dutch roundabout design and why you should NOT copy it

A few days ago a new Dutch "slow turbo" roundabout design appeared in images on Twitter. Ordinarily, turbo roundabouts are used in the Netherlands to deal with large volumes of high speed motor vehicles in locations such as motorway junctions, which are rarely visible to cyclists and pedestrians, but this new design is intended to be used in areas with high volumes of cyclists and pedestrians:
A promising design, but with unproven safety record so don't copy this yet.
This roundabout is interesting because it combines the safe layout of the proven safest Dutch roundabout design with priority for cyclists at the crossings, when similar layouts have previously only been used where drivers are given priority at the crossings. Extra care has been taken in the design to try to ensure cyclist safety at these priority crossings - a factor which has been proven in the past to lead to a sharp reduction in safety.

A particularly poor "with priority"
design. No sight-lines, no reaction time
Frequent injuries at this location.
This design attempts to reduce the safety problem for cyclists with priority at roundabout arm crossings by a number of measures:

  1. It slows both cyclists (by tight corner radii) and drivers (by use of narrow lanes with raised tables), giving both more time to react at the crossing.
  2. Good sight lines are ensured because cyclists and drivers cross at right angles to one another.
  3. While turbo-roundabouts require multiple lanes, this design keeps the cycle crossings far enough from the roundabout that cyclists are required to cross only one lane of motor vehicles at a time.
  4. A generously sized safe refuge is provided between the two streams of traffic.
  5. The crossings being placed at a considerable distance from the roundabout itself means that the moment in time when drivers negotiate with cyclists on the crossing is distinctly different from that when they have to negotiate with other drivers on the roundabout.

Why it may not be so safe as is hoped
I think there is great promise in this design but I must sound a note of caution.

Raised tables slow motor vehicles where
cyclists have priority at the crossings, but
they resemble less successful crossings.
I am enthusiastic about the possibilities for this type of roundabout because it follows the good design principles of the proven safe Dutch roundabout design as I discussed in the previous section and that it also gives cyclists priority (everyone wants priority), but I also see reasons why it may fail to be safe. For instance:
  1. The distance between the crossings and the roundabout is quite large, but for drivers entering the roundabout the distance between the crossing and the point where they need to choose a lane is very short. This may distract drivers such that they are less likely to notice cyclists.
  2. Raised tables on straight roads have only a slight effect of slowing drivers. When I looked at three different priority crossings a few days ago, the crossings where drivers were effectively slowed had more measures than just a raised table and the example which barely slowed drivers at all looked very much like these crossings.
  3. This isn't the first time that priority has been combined with a layout which provides better sight-lines. For example, one attempt to design a roundabout in Eindhoven combining good sight-lines with cyclist priority resulted in some injuries.
I remain hopeful about this design, but we must keep in mind that it is an experiment.

Experiments are not always successful
Without experimentation we can never discover new and perhaps better ways of doing things. The Netherlands leads the world in cycling infrastructure design, and experimentation continues here. This is a good thing. But ideas should only be adopted more widely if they have been proven to work safely and efficiently.

Experiments which didn't work out so well include an experimental cycle-path surface which was installed near Assen in 2009, but then replaced again in 2013 after it had proven not to provide an adequately comfortable surface for cycling.

There was also the Zwolle "fietsrotonde" for which bold claims were made in advance, but where poor design caused injuries within months of opening.

As of right now, there is precisely one roundabout of this new design in the world. It should be viewed as a brave and worthwhile experiment and it may eventually form the basis for yet safer conditions for cyclists in the Netherlands, but it should not yet form the basis for other experimentation elsewhere. We do not yet have long term accident statistics for this design and it is premature to make any claim about whether or not this new design is in fact safe.

Note also that the new design requires a very large footprint in order to provide the required sight-lines and space for the lanes of the turbo roundabout. As such, it's unlikely to be able to be applied everywhere.

What to adopt in other countries
For experimentation elsewhere it makes most sense to copy the proven safest Dutch designs. So far as roundabouts are concerned, this is it:
This design provides the best basis for emulation elsewhere. Such roundabouts have the the best safety record within the Netherlands and are likely to remain safe even if aspects of the design are compromised.
The safest design currently in use in the Netherlands, shown in this photo, places the emphasis on cyclists to look after their own safety rather than relying upon perfect driver behaviour to keep cyclists safe. This is one of the reasons why this design is successful. The same principles have also been shown to work on similarly designed roundabouts with considerably smaller footprints.

Awful roundabout design from London
widely described as "Dutch", but
actually nothing of the sort. This is
one of many awful recent proposals
from London, none of which are
similar to Dutch designs which they
claim to have copied.
The details of any design are important. Distance between roundabouts and crossings, heights of raised tables, lane widths, road camber, geometry are all important and none of these should be taken as being the sole reason why Dutch roundabout designs are safe for cyclists. It should also be noted that roundabouts are only used by cyclists in the Netherlands where traffic volumes and speeds are relatively low and are controlled. Unfortunately, it is not uncommon for designers elsewhere to completely misunderstand how Dutch roundabouts achieve their safety. "Cargo-cult" style copies of Dutch roundabouts built in the UK in Bedford, Cambridge and York without the safety features of the Dutch roundabouts which provided inspiration and as a result they are not so safe.

In order to try to assist planners and campaigners alike to make the right choices, we offer cycling study tours which take a unique, independent, view of Dutch cycling infrastructure and which explain everything in plain (native) English. Book a place to discover more about what works well and should inspire new infrastructure design elsewhere as well as what works less well and should not be copied.

Find out how how things really work in the Netherlands before trying to copy anything.