Building Blocks

Cargo trike

Think of transport infrastructure as a house. The component parts are items such as bricks, windows, and tiles. The quality of the finished product will be dependent not just on the quality of the components, but also how they are put together. This article will describe some of the important component parts of Dutch system infrastructure that are relevant to cycling, but not how the component parts are put together. It is important to understand that if the component parts are used outside of their proper context, they may well improve conditions for cyclists at the point where they are used, but they wont improve conditions overall. For example, if one places a clever junction design at the intersection of several roads, but then require cyclists to use the carriageway to get to the junction, the only people who are going to benefit from the junction are the few people who are sufficiently risk tolerant that they are prepared to ride on busy carriageways. Such a junction may result in existing cyclists taking advantage of it, it wont result in much, if any, increase in cycling. That said, if highways engineers don't take opportunities to implement the building blocks of cycle-friendly infrastructure, we will never make progress towards sustainable transport. That does not mean every junction needs to be cycle-friendly, because Dutch system infrastructure unravels modes of transport and some junctions will never see cycle traffic. Clearly it would be a waste of money building a junction to handle cycle traffic that never passes through that junction. But it is necessary to have a guiding plan that shows which junctions will need cycling infrastructure, and which will not.

Not everything Dutch is good. Sometimes the Dutch fail to follow their own rules and end up with something that doesn't work. Their failures look remarkably similar to British attempts at cycling infrastructure, such as lanes that are too narrow, bends that are far too severe, conflict-ridden shared paths, and junctions that require people to have eyes in the back of their heads. They also experiment with new ideas, and those ideas don't always work out too well. And there are many obsolete ideas, such as advanced stopped lines, that one can still find in use. This article limits itself to current best practice.

When reading this, keep in mind also that in the Netherlands cycle traffic is just one form of traffic using what is effectively a light transport network.

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Contrary to what British cyclists think, Dutch cyclists ride on the carriageway rather a lot. However, various methods are used to limit the activities of heavy vehicles on those carriageways that are shared with light vehicles, so the experience of cycling on the carriageway is very different to that in Britain.

Restricted access streetA method familiar to British people is to pedestrianise town centres. Roads in the pedestrian area will either be cul-de-sacs, or they will force drivers back along an adjacent road to the point at which they entered the pedestrian area, making them useless as through-routes. Vehicles (including bikes) still have a carriageway, and pedestrians have footways free of cycle traffic, so everyone understands how to use the area safely.

This method is often combined with making roads one way for heavy vehicles, but unlike in Britain the lane that is freed up is used to create cycle lanes that allow bidirectional travel. A cyclist can thus take the most direct route. The one-way streets will be arranged to make them difficult to use as through routes by heavy vehicles. Note that cycling contraflow to motorists is not dangerous, because there is so little heavy vehicular traffic. Consequently there wont always be marked lanes as shown in the photo.

A third technique is to simply close a road to heavy vehicles at some point, but leave it open to light vehicles. The simplest way to achieve this is with a line of bollards.

These techniques are known as filtered permeability.

Some roads in Britain and the Netherlands have “service roads”. These are short sections of carriageway parallel to the main road that effectively make a busy road quieter for residents. The Dutch join these together with cycle paths, creating a safe cycle route next to a busy road. Of course once car usage has been drastically cut, as it has been in the Netherlands as a result of promoting cycling, roads that were previously dual carriageways can be reduced to one carriageway, and the remaining carriageway closed at intervals along its length to through motorised traffic. This too creates a safe cycle route.

Shared carriageways always have a very low speed limit, but of course it's important not to make the road look and feel like a fast road or people will drive fast. Whilst purely visual effects are helpful, the best way to make a driver slow down is to give them something to steer around. On new roads this can be achieved simply by making the road sinuous. On existing roads that were built straight, this can be achieved by alternating the side on which parking is allowed. The alternated parking can be so arranged that at a crossroads the junction becomes staggered. Both the visual effect and the physical need to steer the car to cross the junction slows down drivers.

  Alternated parkingParking is alternated from one side of the street to the other, creating chicanes on an otherwise straight road.   Staggered junction created using alternated parkingThe parking alternation on two roads has been arranged so that the junction is staggered where originally the road simply went straight across.  

Bollards and Tight CornersSpeed cushions are not used; they are a distraction for drivers and encourage them to take up a road position that may disadvantage other road users. They also create maintenance issues. However, speed tables are used at junctions to encourage drivers to traverse junctions at a safe speed. Radii are kept tight, as the tighter the curve the slower the vehicle must be driven. Bollards are used to prevent corner-cutting.

Rural road closed to road vehicles to make it quiet and suitable for cyclingThe techniques used to calm and reduce heavy vehicular traffic on urban streets are used also in the country. Minor roads have literally been ripped up part way along their length so they are no longer through-routes for heavy vehicles, and where this has been done a bypass with an all-weather surface is provided for cyclists. With much reduced motor traffic, these roads become pleasant cycle routes. Farm machinery (which of course has off-road capability) can still use such roads as through-routes, so this arrangement doesn't conflict with the needs of farmers.

More major roads don't have all these features, of course, as they are designed for fast and efficient driving. However, every time a major road passes into an urban area there will be a speed limit reduction and a Chicanechicane. These are not the problem they are in the British context, where cyclists would find motorists racing them into the gap and / or tailgating them through the gap, because cyclists are provided with a segregated cycle path on such roads (this can be seen to the left of the carriageway in the photo). Chicanes are widely used in Germany for the same purpose.

Island bus stopCycle paths are designed to be free of anything that would interfere with the progress of a cyclist. There are no awkward barriers to negotiate, and even bollards are being removed because they have proved to be a danger to older cyclists. Cycle paths pass behind bus stops, and passengers wait on an island. This minimises conflict between pedestrians and cyclists, and completely eliminates conflict with buses. Buses never share the road with cycles, because the two modes of transport are totally incompatible and mixing the two causes problems for both.

Cycle paths are invariably wide, being an absolute minimum of 1.7m (unidirectional), but preferably 2m wide. Bidirectional paths are double that. This is necessary to ensure cyclists can pass each other safely. Paths are designed to be as straight and direct as possible, because sinuous paths just sap energy and make cycling slow. This contrasts with the UK, where paths are designed to slow down cyclists, making cycling slow, laborious, and unattractive.

Bevelled or forgiving kerbMore recent paths have bevelled kerb stones. These increase the effective width of the path, because there is no risk of a pedal hitting the kerb. Additionally any wheel that makes contact with the kerb will ride over it safely, rather than forcibly dismounting the rider. This is an example of objective safety, meaning it has a direct effect on injury rates.

Surfaces vary widely. Block paving is quite common in the Netherlands, but does not make for a good ride. Bitmac is much smoother, but it is not in fact the best surface, as the Dutch have developed a special low rolling-resistance concrete. This is laid in continuous sections (as much as can be laid in a day), and then an angle grinder is used to create expansion gaps that a wheel will pass over smoothly. The difference between this surface and bitmac is very noticeable as a change in the effort required to propel the bike. The light colour is also beneficial, as it makes it easier to see the path at night if it is unlit.

In urban areas cycle paths are lit. This may be standard street lighting, or it may have various clever features to reduce energy consumption and light pollution, such as automated or manually operated switching to increase the light level when cyclists are present. Where lighting might affect wildlife, special narrow-band lighting is used. To humans this appears to have a noticeable green tint, because human vision is most sensitive to green light. Thus giving the light a green tint allows a reduction in the brightness of the lighting, which reduces it's effect on nocturnal wildlife. Lighting increases subjective safety and social safety. Subjective safety is how safe something feels, and has an impact on whether people are willing to cycle or not. The poor subjective safety of British roads is the reason why hardly anyone cycles in the UK. Social safety refers to the likelihood of being attacked. Good street lighting reduces the number of places where an attacker can hide. All three forms of safety are important when designing infrastructure that fosters mass cycling.

Crossings

Side road crossingCycle paths typically have priority over side roads, if possible crossing a few metres behind the mouth of the junction to ensure good sight-lines and to provide space in which a car can stop for the crossing. The path may be on a raised platform to encourage vehicles on the carriageway to slow down in time, but if it isn't it will be at the same grade as the carriageway to ensure a smooth ride (there is not even a dropped kerb). Radii are made tight to encourage low speeds, and this also reduces the need to check behind when crossing a side road.

Central refuge on cycle crossingWhere a cycle path crosses the carriageway away from a road junction one of two types of crossing will be provided. Where a signalised crossing is not required a refuge will often be provided that is large enough for cyclists to wait in the middle, making it easier to cross the road. This might look like the pinch-point crossings hated by British cyclists, but cyclists never have to cycle through them on the carriageway so there is no possibility of drivers racing them into the gap.

If a signalised crossing is considered necessary, it will either idle in favour of cyclists, or it will switch the carriageway traffic phase to amber the instant it is triggered by a cyclist. Typically the trigger will be an induction loop, but manual operation is possible too. There will be one crossing for the entire width of the carriageway; cyclists do not have to slowly work their way across multi-stage crossings. Also unlike the UK, cyclists do not share the crossing with pedestrians, as that just causes conflict. The arrangements of the lights themselves is also more sensible. A standard size traffic light is provided before the crossing for approaching light traffic, and a repeater is provided for people waiting at the crossing. Note that this is positioned nearby, not on the opposite side of the road, or just a few centimetres from a cyclist's hip where it cannot be seen (the two standard arrangements in the UK).

Roundabouts

Plan view of a Dutch roundaboutWith the exception of turbo roundabouts (two lane high speed, high capacity roundabouts for motorised traffic), multi-lane roundabouts simply do not exist in the Netherlands (and are very rare in Germany), as they are considered too dangerous. All roundabouts are single lane, but whilst this would make them relatively easy to negotiate on a vehicle such as a bike, for the most part light vehicles do not share the carriageway with heavy vehicles. The best design of roundabout is shown here in plan view and from street level.

The bidirectional cycle path runs around the circumference, separated from the carriageway by a margin. Being bidirectional, those using it can take the shortest route around the roundabout. However, the paths joining it may be bidirectional or unidirectional. Light vehicles do not have priority where the paths cross the carriageway (because this tends to result in collisions), but various techniques have been adopted to aid crossing. Firstly the carriageway on the roundabout has an adverse camber, which discourages motorists from driving too fast. Secondly the radii are kept as tight as possible to stop motorists from exiting too fast. And thirdly an island large enough for the length of a bike is provided between the two carriageway lanes, allowing one lane to be crossed at a time. Note that the crossing point is set back from the roundabout itself, both to improve sight-lines and to provide a space in which a car can stop without blocking the roundabout. The net result is a roundabout that is very safe for all users, but which doesn't impede progress excessively. In practice many motorists will pause to allow people to cross the carriageway, no-one has to wait more than a very short time, and more often than not all that is required is a slight reduction in speed.

Street level view of a Dutch roundaboutStreet level view of a Dutch roundaboutStreet level view of a Dutch roundabout

High Capacity Junctions

Underpass with unobstructed view to the far sideExcepting cloverleaf junctions and turbo roundabouts, which are relevant only to heavy vehicles, junctions that require a higher capacity than can be achieved with a single lane roundabout are always signalised. If possible the junction will be designed so that cyclists do not have to wait at traffic lights, because stopping and re-starting a human-powered vehicle takes a lot of energy and reduces the range of cyclists. So at a T-junction, for example, cyclists who do not need to cross the carriageway will find the traffic lights are bypassed. At a more complex junction there may be grade separation. Typically this means an underpass, but these are designed to provide a clear view from the approach to the exit, both to eliminate collisions at blind corners, and to eliminate places where an attacker could hide (making Dutch underpasses feel safe to use, unlike British underpasses, where ninety degree turns are the norm). Note that in the photo the road rises slightly at this point to reduce the effort required by cyclists.

If a controlled junction is not bypassed, light vehicular traffic will always have its own phase, to ensure segregation. The arrangement most familiar to British people will be to have a crossing on every arm. However, unlike British crossings these will not be multi-stage toucan crossings, but single-stage dedicated crossings. Additional crossings will be provided for pedestrians. The disadvantage of this arrangement is that it requires cyclists turning right to wait twice. This problem becomes progressively worse as more arms are added. These problems are solved by the simultaneous green junction.

Simultaneous green cycle traffic flowAt a simultaneous green junction the heavy vehicular traffic will have conventional traffic light phasing, but if the system detects the presence of light vehicular traffic, a simultaneous green phase will be triggered for it. Simultaneous green means all directions are given a green light at the same time. This works because light vehicular traffic is moving relatively slowly through an area designed to be big enough for large, fast vehicles, so people can easily stop to wait for someone to pass, or steer behind one and other. More interestingly, when there is little traffic the paths that people take through the junction means that they tend not to meet each other. For example, those following the blue arrow in the picture will arrive at the point where they cross the yellow arrow after the people following the yellow arrow have crossed the junction, so they will never actually meet. Of course it doesn't always work out that neatly, but it does mean that there is nothing like the degree of conflict there would be if, say, everyone tried to pass across the junction diagonally (which would mean everyone would meet in the middle simultaneously). During the simultaneous green phase a hundred people can cross the junction in a few seconds, so the arrangement has little impact on the heavy vehicular traffic (indeed, it is the heavy vehicular traffic that limits the capacity of the junction). However, the capacity is further enhanced by allowing right-turning light vehicles to turn at all times. This is completely safe because these people are turning into a cycle lane that would otherwise be unoccupied. Simultaneous green junctions are highly scalable. The design will cope with any number of arms of any width, and as can be seen from the example shown, there are no problems catering for pedestrians (using a pedestrian phase). One simultaneous green junction in Groningen even has a bascule bridge on one arm, allowing yachts to pass by on the adjacent canal.

Cycle Parking

The sheer scale of cycle parking on the continent has to be seen to be believed. It is quite common for the parking in key places, such as stations and town centres, to accommodate many thousands of bikes. At these locations sensors determine if a bike has been abandoned, so it is known these parking places are in active use. However, the whole point of a bike is that it is door-to-door transport, so it is important to ensure that parking is widespread, and indeed it is. Every shopping centre, no matter how small, will have spaces for cycles. Every school will have cycle parking. Indeed anywhere where people come together, there will be cycle parking.

Cycle parking is a critical part of cycling infrastructure, because people do not want to leave their bike somewhere it might be stolen. If a destination lacks somewhere reasonably secure to leave a bike, people simply wont cycle there.

  Cycle Parking at Ikea, GroningenIn the Netherlands people cycle to Ikea. Large flat-bed cargo trikes are available for carrying home purchases (photo at top of page).   School cycle parking in AssenThis is part of the cycle parking for a recently built school in Assen. The infrastructure in many northern European countries enables safe, practical cycling.   Uncovered cycle parking in AssenA city like Groningen has and requires tens of thousands of parking spaces for bikes, and they are actively used.  
  Bus stop cycle parkingCycle parking at a rural bus stop allows people to cycle to the bus stop. This allows the bus to take a direct, fast route, making rural bus travel practical.   Cycle parking at a local shopping centre in AssenShops on the continent know their customers arrive by bike, not in a car, so even small shopping centres have cycle parking.   Covered cycle parking at Kiel HauptbahnhofCompared to other northern European countries the UK is unusual in not having mass cycling. This covered, secure cycle parking is at Kiel station, in Germany.  

Signposting

Signposting is important not just to help people who are cycling, but also to indicate to motorists that they could be making their journey by bike rather than sitting in a traffic jam. It has to be said that signposting for cyclists is at its best in Germany. The signs are plentiful and so detailed that it is often possible to locate a signpost using a photograph of it and a bit of time spent with Google maps. It's not that the sign posts are complicated or expensive though, as they are more simply engineered than in the UK. The Dutch do have similar signposts, but the more interesting design is the mushroom signpost. These have the great advantage that they will be illuminated at night by a cycle head lamp, whereas more traditional designs can be tricky to read.

  German signpost for cyclistsA simple but detailed and useful signpost in Germany   Dutch mushroom signpostA Dutch mushroom signpost  

 

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