In a recent thread, “OrangeKiwi” posted this link to an aerial image of a roundabout in the Netherlands, which is also shown below. Looking at this aerial reminded me of just how much I love the Netherlands. Having recently returned to Auckland after living/studying in Amsterdam for a year I’m definitely feeling the transport culture shock.
Some of the nice design elements of this roundabout include:
- Pedestrian crossings on all approaches (O.M.G.)
- Dedicated cycle lanes approaching and around the roundabout (O.M.G.)
- Notably “non-flared” (i.e. straight) vehicle approaches, which encourage vehicles to slow down before entering the roundabout
- An abundance of street trees and landscaping
It’s the overwhelming attention to detail in Dutch street design that I find most impressive. And what I wanted to highlight in this post is just how all these design elements add up to define the amenity and safety associated with the wider pedestrian environment. To get things started, in the images below I’ve calculated some key dimensions for two roundabouts; the one shown above from the Netherlands and one from Auckland (Dannemora). Both are reasonably modern single lane roundabouts located in urban residential environments. In fact I’d probably suggest that the one in the Netherlands probably occupies a relatively strategic location in the wider street network, whereas the one in Auckland is much more sedate – hence should have a smaller footprint.
The reality is quite different. In the image below you can see that the roundabout geometry in the Netherlands is generally smaller, especially in terms of the width of the lanes approaching the roundabout, which are only approximately 3.1m wide in the Netherlands versus 5m in New Zealand. The increased width of approach lanes in the Auckland roundabout seems to be entirely attributable to the way that on-street parking has been accommodated within the street cross-section: As you approach the Dutch roundabout you find that on-street parking has been accommodated in a distinct tiled area located to the side of the approach lane, but in the Auckland roundabout we’ve just widened that puppy out. This effectively means that whenever there are no cars parked on-street (and often there won’t be), then Auckland’s drivers will have enough tarmac to launch themselves into orbit around the roundabout at Mach 3 speed, which means that the intersection will be that much less safe for everyone.
But how do these geometric differences impact on the wider pedestrian environment? One of the key parameters for pedestrians is what I call the “walk circumference” of the roundabout – that is the distance a pedestrian would have to walk to get around the roundabout (NB: No one would actually walk all the way around a roundabout, but all pedestrians will walk at least partway around). In the case of the Dutch roundabout we see that the walk circumference is 170m, whereas in the Auckland roundabout it blows out to 200m. So what this tells us is that our simple geometric choices have increased the distance pedestrians must walk by approximately 15% – and that’s even before additional delays associated with the lack of pedestrian crossings is included.
Perhaps as interesting as the difference in the lengths of the walk circumference between these two roundabouts is the difference in their underlying shapes. If you look at the walk circumference paths drawn above you can see that the Dutch roundabout traces out an almost perfect circle. This means that pedestrians navigating the Dutch roundabout will (at almost all times) feel more or less like they are travelling in the direction that they want to go. Contrast this with the Auckland roundabout, where the walk circumference traces out more of a “Prussian cross” like shape. Where the walk circumference bends away from the roundabout, pedestrians will feel like they are walking (curving) away from their intended direction of travel. While some of you might think this is a very subtle difference, I’m fairly confident that it is an important determinant of whether pedestrians will follow the path that was provided for them, or instead find their own path across the roundabout – where the latter is undesirable for all road users.
So it seems that the Dutch could teach us a thing or two about street design. One is that the physical footprint of our vehicle lanes is simply too wide, especially as one approaches intersections, and the other is that we should design our pedestrian paths so that they feel direct – even if we are asking people to deviate slightly for reasons of safety. Ultimately, this comparison went a long way to reaffirming why I felt so much at home in the Netherlands: As a pedestrian or cyclists you feel like the streets have been designed partly with your needs in mind.
That’s not to suggest that in the Netherlands pedestrians or cyclists always have right-of-way, because they most certainly don’t in some places (and for good reason), but it is to suggest that the needs of pedestrians and cyclists are at least almost always respected. As discussed in my last post, there are many intersections in Auckland City Centre itself where pedestrians could not cross the road even if they were prepared to wait for a signal, let alone enjoy the kinds of dedicated crossings available in the Netherlands, even at roundabouts located in residential neighbourhoods of small towns.
All this begs the questions of why pedestrian/cycle design in New Zealand lags so far behind many places and how we might do better? To get the ball rolling I’d suggest that we should consider the forced immigration of the entire Dutch women’s hockey team, along with the forced deportation of all traffic engineers over the age of 30. There may be other potential solutions – what do you think?