Voorrangsplein! Part 1

My trip to the Netherlands in 2017 seems a long way in the past and I'm itching to go on another visit. I have no idea when it will be possible and so I have to rely on my photos, Google Streetview and reading up on innovations and there's another junction type which I didn't quite manage to see.

I like the Dutch approach to road junction design as it stems from their Sustainable Safety approach. Perhaps the most exotic and lesser known junctions is the wonderfully named "voorrangsplein", which translates as "priority square". It's for use in situations where there are quieter side roads which need connecting to busier main roads where the use of traffic signals and roundabouts are avoided.

A roundabout would operate where all of the arms had broadly similar traffic flows, whereas signals might be used where flows are unbalanced or there are several traffic lanes involved. Of course, grade separation remains for the busiest situations. 

The voorrangsplein usefully fills a gap. In the UK, you'll be familiar with right turn pockets for traffic. That is, right turning drivers enter a little right turn lane before completing the turn into the side road. This is sustainable safety in action. First we allow drivers to concentrate on entering the right turn pocket which takes them out of the general traffic stream, helpfully dealing with the risk of rear-end shunts. Once positioned in the right turn pocket, they can wait until there is a safe gap in oncoming traffic to actually make the turn.

It also follows that this arrangement is safer where there are single traffic lanes in each direction because there is always the risk of a driver not checking that all oncoming lanes are clear when turning. We have a lot of dual carriageway layouts in the UK where signalised junctions are used with right turn lanes, but where right turning drivers are completing turns over two oncoming lanes. It's far better to separate conflicting movements in time in these situations. It also explains why uncontrolled right turns from high speed dual-carriageway roads are gradually being removed because of the unsafe nature of the layouts.

The problem with the right turn pocket approach is that it can often be very difficult to turn right from the side road because one needs to deal with traffic from the right, then traffic in the right turning pocket and then joining through traffic from the left. We have solved one problem and created another. The voorrangsplein design breaks down all of the movements into steps so that the driver only has to cope with one thing at a time.

The image above from Dutch Urban Index shows a voorrangsplein to the south of Driemond, a town just to the southeast of Amsterdam. The main road is the N236, a regional road, providing a through route function for longer distance traffic and so can be quite busy. The junction has access to the town (top right) and local access either side of the canal - and it is local access, there is no route through for general traffic (below - I actually cycled through the junction when it was at the start of its rebuild).

It's a little complex to understand what is happening and so let's stop and think about how such a layout could be applied in the UK. For roads like the N236, we might look upon them like we would rural single carriageway A-roads. Even if we didn't formally look at them in that way, a similar design approach is likely and so many engineers would reach for the Design Manual for Roads & Bridges, notably CD123, Geometric design of at-grade priority and signal-controlled junctions.

At the basic level, the voorrangsplein takes a single carriageway road and locally duals it (known as Single Lane Dualling - SLD). I would caution the point again that for the voorrangsplein, the side road traffic won't be significant because otherwise we'd be looking at a roundabout or signals. Here's a DMRB layout;

It's fine if you're turning right into the side road because you've space to get out of the main traffic flow before you decide to cross oncoming traffic. In essence, the movement is broken down into two parts. However, the main problem here is turning right out of the side road which is going to be tricky, because as I mentioned above, there are essentially three traffic lanes to deal with.

In an earlier incarnation of the DBRB there was a method of regulating priority within the central reserve of a priority junction (TD42/95 for the geeks). This was an attempt to hold drivers turning right into the side road in order to assist drivers turning right out of the side road. There are still live versions of this confusing and risky layout out there, but it's not a safe design which is why I assume it is not in CD123.

The image above is the junction of the A1306 New Road and B1335 Sandy Lane on the London/ Thurrock border. It was a very confusing layout which was designed to help drivers turn right from Sandy Lane (off to the right). The problem was that the side road movements were pretty busy and despite island-separated lanes, gives ways and red hatching, the junction had a shocking casualty rate with many deaths and serious injuries. 

A few years ago, the junction was rebuilt as a roundabout and while there are still crashes occurring, they are far less frequent and of a lesser severity. This is down to providing a junction arrangement which is easier for people to understand and suitable for busy side road which is probably similar in terms of flows as the main road arms. This is an aside from the voorrangsplein, but merely shows that the old UK approach to managing right turns from side roads in this type of situation was a dangerous failure. A voorrangsplein would not have been suitable here because the side road is too busy.

So, what would a UK voorrangsplein look like? The image below gives a flavour and as I have drawn it with drivers on the left, it's going to be a bit easier to explain. I would state that we'd struggle to build one of these on a trunk road (as controlled by Highways England and the devolved governments) because it doesn't appear in the DMRB and innovation in layout doesn't seem to hold much interest. In theory, a local highway authority could build one though.

As you can see, we have an area of Single Lane Dualling to create space in the central reserve within which we manage right turns (Dutch left). Let's zoom in a bit. The green is verge and the light grey is an overrun area just in case we need to accommodate larger vehicles whilst keeping space tight for smaller vehicles.

This is quite different to the UK approach. Considering the right turn from the main road into the side road, we have a right turn pocket (the length of which will vary on how busy the right turn might be). Through traffic is encouraged to slow down with narrow lanes and the deflection created by the central reserve area and so those turning right have some protection from shunt collisions. You will probably want reduce the speed limit if it's an inter-urban route and I would say a maximum of 40mph is likely to be sensible.

Once a driver is in the protection of the central reserve, they have time to consider a gap in oncoming traffic before completing the turn into the side road. So far, so UK-conventional. The key to the voorrangsplein is how right turns out of the side road are managed and protected. An emerging driver doesn't have to worry about getting across three lanes. They do need to find a gap in oncoming traffic, but once they do, they actually turn left and move into the central reserve gap in one go.

As they reach the give way point, the driver again has time to assess a gap in the oncoming traffic without having to worry about anything else - the movement has been broken down into stages. The end of the manoeuvre is the original right turn. The beauty of the arrangement is that it works with all sorts of arrangements such as a left / right stagger (if you are driving from one side road to the other, you would turn left then right);

The CD123 version of this is as below which is perhaps the closest we get to a UK voorrrangsplein;

We can also provide the more complex right / left stagger which relies on traffic signals in CD123;

This works slightly differently. The driver turning right from the main road doesn't complete the turn into the side road, they essentially perform a U-turn before turning left into the side road; but we are still breaking down the manoeuvre. For drivers turning right out of the side road, it's as before. The right / left stagger clearly needs a longer central reserve.

We can also use a voorrangsplein at a crossroads (below). Crossroads can have a poor safety record because drivers are having to find a gap in two different traffic directions. Sustainable Safety breaks down the manoeuvre and so the voorrangsplein allows cross traffic to do so in two parts, as well as providing protected right turns for those wanting to get in or out of the side roads from the main road;

It is worth zooming in for a closer look, because like the right / left stagger we only want drivers emerging from the side road to have to cross one traffic lane and not both the through lane and the right turn pocket;

If we need a little more capacity in the central reserve, we can just lengthen the right pockets after the side road. For example, we may be in farming country and we need a little more space for tractors towing trailers;

With a crossroads, I think it would be a good idea to block the visibility between the two side roads just to try and avoid the potential for a driver to see the road opposite. We want concentration to be on breaking down the movement.

The other UK issue will be signing the layout. The Dutch don't use complicated traffic signs to explain what is happening (other than destination signs). From a UK perspective, we might need a little more help and I could see people wanting to use no entry signs and turn right turns to make sure people don't turn left up the wrong carriageway, but the layout really needs to do the hard work of explaining what to do. 

I can think of lots of locations where a voorrangsplein would be a good junction layout, even locations which are already roundabouts. Next week, I will continue to look at this form of junction to see how we can incorporate walking and cycling. I'll also show you a couple of more urban examples and also some links to other resources on the subject. 

I'll leave you with another Dutch layout, this time on a road running between areas of Langedijk. This is a crossroads with a more suburban feel and you'll see a walking and cycling route crossing the main road at the junction (but not running along it). You'll see that the side roads are opposite the start of the right turn pocket so drivers only need to cross one traffic lane and the deflection created by the central reserve acting as a device to keep things nice and slow.

The Development Management Engineer

One of the most powerful and little-known local highway authority roles is that of the "development management engineer".

It's a role that most people haven't heard of, but it can have such an impact on how developments interact with the highway network, it's something that people need to know more about. This is not to say that the role operates in isolation - that's too simplistic (although it can often operate within a silo).

"Development management" is the friendlier version of "development control", but from a highway authority point of view, there is a need for staff to be involved in the management of the development point of view from an initial enquiry by a developer, through the planning application process and through to the development being delivered on site.

My experience of this process has been from the viewpoint of a developer, a consultant and a highway authority (managing a team with the responsibility). My own experiences from the highway authority point of view were largely positive because my approach was to make sure that I and key members of the team were conversant with planning and transport policy so at the pre-application/ planning application stage, we could give decent and policy compliant advice to developers and planning colleagues (although it frequently irritated some councillors who disagreed with their own policies).

The approach meant that larger planning applications were not a surprise and if a developer decided to depart from policy, then we had the confidence to object. Of course, transport and highway matters are only part of the breadth of considerations needed to properly evaluate a planning application and consents being granted under delegated authority by the chief planner or by the planning committee didn't always go with our view.

Once planning consent was granted, we were there to help the developer get the scheme built where there was an interaction with the highway. This could range from giving some advice on traffic management to service the development all the way to new junctions and significant layout changes which were part of the planning consent.

On the other side of the fence, I have been frustrated by local authority staff who have acted as gatekeepers, but who haven't provided help in navigating the processes - I used to allocate a member of the team at the development phase so the developer only had to deal with one person. My team member would do the internal running around and approval seeking, even to the point where they would book road space for the developer. 

I have also worked with really good local authority staff who embrace the joint working ethic to reach a common aim. The fact that the process can be highly variable is, in my opinion, a barrier and generates inefficiencies for both the highway authority and the developer. The variability comes from how the role is set up within the local authority, the differences in how the same legal requirements processed in different areas and the motivation and support the staff have.

Some authorities have completely separate development management teams which aren't always plugged into the wider corporate policy considerations. Some unitary authorities have highways staff embedded in the planning department which is good from a development point of view, but they are sometimes distant from the projects and operational side of highways management. In some authorities, the development management role is left to junior staff because it can sometimes be repetitive work and some end up with time-served staff who frankly don't put in enough effort because they have a niche that nobody else understands.

I guess many people will be interested in the front end. Just who agreed to yet another awful roundabout which ignores walking and cycling? Why did that fast food outlet get planning consent for an awfully laid out drive-through lane? Why has a new set of traffic signals been built for a housing site with staggered pedestrian crossings?

It's a difficult one to generalise about, but the reasoning should always be rooted in policy. The other thing to look at is if the authority is unitary. Again, it's a generalisation, but with a unitary authority at least the highway and planning functions are in the same organisation. With two-tier arrangements you end up with potential for tension between the planning authority (district council) and highway authority (county council). This often seems worse in cities where a city council is trying to be progressive, but the county council acts as a brake - you certainly hear of stories about rural county councillors being very pro-car to the chagrin of the city councillors.

The development management engineer is also a person with the same prejudices and blinkers as anyone. Some (dare I say at county councils) can be very car-centric people which is shaped by their experiences and by the culture in the authority they work (which comes from the political leadership). These are the places that we see large roundabouts being built because of capacity concerns, rather than compact roundabouts which deal with safety concerns. In fact, the whole issue of ensuring new development doesn't create congestion seems to be driving ever larger highway schemes which attract government funding to enable development which mean places where car ownership is the only transport choice for those to can afford it.

It's unfair to lay all of this at the feet of the development management engineer, but they do have the ability to speak up early and to be right on top of policy. In my opinion, the function should absolutely be carried out by a senior member of staff in order to have clout and influence. For anyone who is interested in better outcomes, it is vital to understand how decisions are made locally and who makes them. This might require a bit of time reading through the consultation papers for a few larger planning applications, obtaining organisational charts from the authority and giving councillors some work in tracking down some of the more opaque parts of the process.

The Politics of Winter Service

I wasn't going to write about winter service this week because I had covered it in two posts during the winter of 2017/18, the latter being a little more of a deep dive.

But, I've changed my mind and it's always useful to think about events and what we can glean from them. In my corner of London we had some snow earlier this week. Under normal circumstances it would have played havoc with road and rail, but the lower demands from people travelling meant that there was resilience in the system. That's not to say that other parts of the UK didn't have problems, but in London we generally don't need to physically plough snow out of the way - our problems tend to be more about icy conditions.

Because I was working from home and I had no errands to run, I didn't go cycling until Friday because based on past experience, you can cycle when the snow starts, but the lack of winter service on shared paths and cycle tracks means that after a few days you've ice to contend with.

As you can see in the photos above, side streets are lower down the winter service pecking order and while main roads remain fully useable, it is only ever the carriageways which get treated. The shared path above still has some nasty patches of ice after several days of people walking across the snow and it getting compacted and refrozen into ice.

Why do we have it run like this? There is obviously a need to keep the carriageways of main roads clear for public transport, emergency response and freight, but this is also in part due the old network and planning hierarchy which places the movement of motor traffic at the top of the list. 

As well as necessary services, the lure of clear main roads also means that people will be trying to drive from their side street to reach these main roads. In quite a lot of cases, people will not be used to driving in icy conditions and so we get to see social media posts full of drivers sliding around - some dangerously risking themselves and others.

What options do people have though? In many ways cars insulate us. In freezing temperatures, it must be tempting for some people to use a car rather than walk or cycle because generally it feels safer to do so that having to cope with the ice. This brings me on to the politics of winter service. Who writes the service plans? Who decides on the priorities?

Thinking of a typical UK highway authority, I would lay odds that most of those involved in planning and operating winter service plans are men and probably men who drive. They see the problem from one of a highway network which has been developed by men over decades and even where there are demographic changes in the authority areas and within the authorities themselves, the network legacy has baked this in.

In high cycling countries and cities, winter service is a little different. Of course, highway network development will have followed a similar evolution as the UK to a point, but once cycling is prioritised, then the demographics of street users dramatically shifts and all of a sudden, prioritising people cycling in winter maintenance plans leads to different outcomes which enable a much more diverse and gender-balanced cohort of people travelling. I'll come back to this shortly.

Take Copenhagen (above). The city is famous for getting out and clearing its cycle tracks as soon as the snow falls. The city has of coursed moved from the chicken and egg debate of deciding to provide cycling infrastructure and with high levels of winter use, the city has also realised that it needs to keep them clear to keep people cycling. This also means equipment is available at the right scale for providing winter service for cycling infrastructure.

The photograph above is a small tractor with a brush for sweeping snow from the cycle tracks in Copenhagen. In the UK, we are gradually seeing investment in such kit in the places where we are building for cycling. Sometimes it's dedicated and sometimes it's added to existing street cleansing machines.

But even in the high cycling places, people walking come a distant third. Carriageways and cycle tracks are generally easy to to keep clear of snow and ice, but footways often have clutter, they are behind lines of parked vehicles, cars parked on footways and because of the way we construct footways, they are often uneven leading to water holding and freezing. In many winter services plans, footways on main roads do get attention, but if your side street footway is sheet ice, then it's little help.

The progressive end of winter service planning lies with the gender balanced approach. In 2015, the Swedish city of Stockholm reviewed its traditional winter maintenance approach and discovered that it disadvantaged women who tended to walk and favoured men who tended to drive - based on clearing carriageways first. They also that three times as many people where injured walking in icy conditions compared with driving. Here's more from Streetsblog USA, including a video.

Of course, the implications are more far-reaching than men vs women when we consider who travels and by which mode; and more importantly, the mix we want to see in the future. Could there be a wider argument that ensuring the footways within a kilometre of shops, schools and community facilities should be treated first to ensure that those without access to a car can satisfy their basic daily needs during cold weather?

This goes back to the politics. Who decides on how streets are developed and managed? Who leads the operational process on how streets are designed and managed? Who is valued as a result? Have a look at your local highway authority's winter service plan and I think you'll be able to answer those three questions with a high degree of confidence.

Better Streets & Camera Enforcement

The enforcement of traffic contraventions has evolved over the years. Once the preserve of traffic police, it has gradually moved over to local authorities, although it's still not universally applicable because of government inertia on moving contravention enforcement being rolled out universally.

As I have mentioned in other posts, the basic UK approach to road rules is that you can do what you like unless there is a legal restriction which is either at the national level (or devolved nations level) such as defining the national speed limits or the local level with traffic orders.

For many years, the enforcement of contraventions of traffic orders was the remit of the police. Parking-related matters were enforced by traffic wardens and moving offences by the police (usually the traffic division). Over the years this has gradually been decriminalised because in many cases contraventions are not seen as criminal.

On the whole, I think decriminalisation is a good thing, although I wish that the legislation had reserved police powers to issue fixed penalties on a civil basis. I won't give you a history lesson on how things have developed, but the change to a civil enforcement approach has taken over 30 years and it will probably continue to develop (in fact it needs to). 

One of the key tools for civil enforcement is closed circuit television (CCTV) with automatic number plate recognition (ANPR). Because of a populist and idiotic campaign by former Communities Secretary, Eric Pickles, councils lost the power to enforce most parking contraventions by CCTV, but the ability to use them for moving offences was retained, although only in theory because their use isn't allowed UK wide (London being a notable exception).

The use of cameras has reared its head again in recent months with the roll out of so-called Low Traffic Neighbourhoods (LTNs) in London. I say so-called, because like anything, the use of engineering measures to filter out motor traffic from side streets is nothing new, but we always need a shorthand to describe a thing, so LTNs are here to stay!

The photograph above was taken by me standing in the middle of a crossroads in the De Beauvoir Town neighbourhood in the London Borough of Hackney. This crossroads had bollards on each arm making the middle of it territory for walking and cycling and creating part of a wider LTN. This filtered crossroads was delivered over 40 years ago and after controversy which would be familiar today.

The De Beauvior Town crossroads filter was cheap to install, it's cheap to maintain. It's simple and effective with barely any impact on the aesthetic of the streets. Personally, I think it might be nice to depave some of the space which was reclaimed, but that's another issue altogether. Legislation and technology has moved on since the 1970s, but communities are once again pushing to reclaim side streets from the explosion of motor traffic we've seen in recent years and so the art of filtering streets is back.

In my view, the most effective schemes are those which use physical measures to make it impossible to drive a motor vehicle through a location where it is banned. Whether it's a line of bollards or some planters as have been used in Enfield (below). It makes it completely obvious to drivers that they cannot get through.

Personally, I am not particularly bothered about people taking motorcycles and mopeds through these filters. Despite them usually being banned, whenever I have seen people sneaking through it has usually been slowly and carefully because motorcyclists don't want to hit anything or anyone as they will come off badly too. I would rather see local deliveries made by cycle, but pizzas by moped are better than pizzas by car.

There are some situations where the filtering of traffic causes a genuine problem for the emergency services, bus operators or because of a particular and very localised issue. For some cases, the use of a removable/ over-runnable bollard or a gate (below) might be enough.

In most cases, this will be something for the fire brigade because if an incident develops, they may need to bring additional resources in. Imagine there's a house fire and there are fire engines in the street with crews fighting the fire. It might be easier to bring kit in from another direction. The way fire responses work is there will be a minimum turnout to a call and if multiple calls from the public are coming in, resources might be stepped up. 

When the fire brigade arrives, an officer will be in charge of making an assessment and further assistance might be called in further along the timeline and so by and large, fire access is not used for the initial response. Police and ambulance services generally don't carry keys to bollards/ gates and wouldn't take their vehicles over flexible bollards (photograph above) because of ground clearance. They would follow the "open" route into the LTN.

If we are left with situations otherwise not manageable, then we have cameras. They have enabled filtering which may have not been considered before. For example, a bus gate (above) can give public transport a direct route advantage with private car drivers having to go the long way around. We can using rising bollards, but they come with their own maintenance and operational issues. An exemption list can exclude known registrations from enforcement and because buses and emergency services vehicles aren't changed too often, it isn't that difficult to manage. For those which slip through, it's pretty obvious to an appeals processor what a bus or ambulance looks like!

Camera use does rely on having a street layout which makes it obvious to drivers that they cannot go through. The example above is really obvious but it doesn't sit well in the street scene. I think this is hard to get right. The photograph below is in Hackney. The red "road closed" is temporary and so the filter will eventually rely on people obeying the "no motor vehicles" signs. 

The planters help show something different is going on, but I think there is a better way to lay out a filter like this. If there's space, then having planters offset means a driver will have a planter right in front of them and will have to make a real and conscious effort to turn to get round it (you can leave a nearside gap for cycle traffic, but it's not entirely required.

The image above shows the offset arrangement (upper panel) which is easy enough to drive a fire engine around but it makes it more obvious to a driver they shouldn't go through (lower panel). It might just help deal a bit with the whine from people who say they didn't know.

ANPR cameras are not cheap, although it is always difficult to pin costs down because each local authority approaches things in a different way. I put in a FOI to my local authority for a school streets scheme. The capital (purchase) cost for the cameras was just under £10k each. If you add in costs for a mobile phone data connection, back office software for processing ANPR images, traffic signs, traffic orders, staffing costs to design and set up the project and so on, the costs came in at around £40k per site. Once set up, there are ongoing annual revenue costs of maintenance, staffing (processing of fines, managing those staff etc).

People will say that the costs are recouped through fines, but the problem with that is that we don't want people driving through because it defeats the object of having a filter in the first place even if it takes relatively few fines to actually balance the costs of running a site for a year. It also means that managing the camera is very sensitive to other pressures such as staffing costs/ cuts as well as telephone and software costs.

In a few cases, residents are agitating for exemptions. From a technical point of view this would mean obtaining the registrations of residents' vehicles and adding them to an automatically applied exemptions list. From a traffic order point of view, this would need to be a permit scheme (with signage reflecting this) and permits can be charged for which would (should) cover the costs. 

The problem for me with this is that these residents don't want other people driving through their area, but want the full convenience to drive out of their local LTN however so they choose. Even if this is a limited number of vehicle movements per day, it does nothing to nudge residents into taking more sustainable choices and it maintains a certain level of road danger for people not driving within the LTN. Lower traffic means everyone should be playing their part.

This can be challenging for blue badge holders (who can be drivers or passengers) where they absolutely rely on cars for their daily needs and who may be genuinely impacted by a scheme. The only solution here is engagement and it may be that swapping a physical filter for a well-designed ANPR filter is a reasonable adjustment to make, although in the case of non-driving blue badge holders, monitoring the vehicles that they are passengers in will take effort to get right. Of course like anyone, blue badge holders move away from an area and so having a process of periodic review is also needed.

The only way to do this fairly is to properly work through the issues. It may be that as we move to a lower traffic future, the disbenefits for some people disappear. For example, a general drop in traffic on main roads (through other policy and engineering changes) might mean that fears from emergency services are not realised or diminish to the point where a filter can be changed from a camera-enforced arrangement to a physical one. 

Cities are not set in stone and things change, but there needs to be boldness to break the cycle of car-dominance and I remain fully convinced that LTNs are a key catalyst for this, but if we are considering cameras, this needs to be properly and robustly assessed and not a first resort in order to avoid difficult conversations or engagement. 

One significant issue to leave you with is that camera enforcement is very much a London option because some 16 years after it was brought into force, Part 6 of the Traffic Management Act 2004 hasn't been enacted despite councils wanting it to be (England and Wales). For Scotland, I have had a dig around and although cameras can be used to enforce parking and low emission zones, it appears that moving traffic matters remain with the police - if anyone knows more, please do let me know. for Northern Ireland, it's even harder to work out what is going on, but it seems enforcement lies with the police. Again, any local knowledge would be gratefully accepted.