Saturday, 7 October 2017

I've seen things you people wouldn't believe: Part 4 - Time & Space

This week, my taste of Dutch cycling infrastructure has a little look at how space and time are used to get people cycling through busy junctions.

Just along from the side road I looked at last time, Middenweg intersects with Kruislaan to form a signalised crossroads. Middenweg runs southeast to northwest (towards central Amsterdam) and Kruislaan runs southwest to northeast. The northeastern arm connects to the University of Amsterdam Science Park and the southwestern arm is a distributor type road connecting with residential areas and other suburbs (but not as large a road as Middenweg). 

I should state that this is just one junction - others are available in terms of layout and operation and there are issues here which I'll cover later. Hindsight is wonderful as in researching this post, I have found out I could have seen another roundabout and some serious railway overpasses

But, it was a holiday and I was out for a cycle with my son who had to keep stopping for me to take photos!

The photo above shows Middenweg as we cycled northwest towards central Amsterdam. As we've come to expect on big roads, we've motor traffic in its own space (with a tram in the middle), a verge for trees and highway "stuff" (and to provide a safety buffer for people cycling), a smooth red cycletrack and footway, raised slightly above the cycle track. The kerb between the cycle track and the footway is not forgiving (sloped) which shows that even the Dutch can be behind their own best practice!

As we get closer to the junction, the verge becomes a narrower paved strip to give way for a left turn traffic lane.

As we get to the junction, we can see quite a lot going on;
  • Cycle track narrows and moves left to create pedestrian refuge,
  • The pedestrian crossing of the cycle track is a zebra, whereas the crossing of the carriageway is signalised (green man) with a push button demand,
  • Left hand motor traffic lane has a green signal (hard to see, but it's there) and left turning driver is waiting for the oncoming tram to pass,
  • Cycles have a green signal, so they're running at the same time as the ahead/ left motor traffic lane, but there's no "free" right turn for cycles,
  • Right hand motor traffic lane is held on red with a red arrow signal,
  • The right turn traffic signal has a low level signal.

The photo above is a panorama of the junction, taken from a different position from the previous photo. To the left is Kruislann (towards the science park), the cycle track running into the distance is Middenweg (looking at where the previous photo was taken from), middle right is the other arm of Kruislaan and to the right (where the bus is coming from) is Middenweg which continues into the city.

The photo above shows a closer view of a little island which is used on three corners of the junction. It's essentially a remnant of the space left when setting out cycle tracks around the junction with gaps for access. The idea of the layout is drivers turning right will see people crossing (where the signal arrangements mix in this way).

Let's watch a video - first we see people using the junction and then I film a left turn which has to take place in two stages because of the way the junction works.

You'll have noticed that ahead cycling runs with ahead traffic and on Middenweg (the road with the trams), right turning traffic is held to remove the risk of right hook. On the other hand, you'll see on the later section of the video (from a cycling position on Kruislaan), right turning traffic is not held, hence the 'Let Op' sign warning of right hooks as traffic and cycles move together. 

The layout (where traffic right turns are not held) does have the cycle stop line way beyond that of the driver. The theory is that drivers turning right will be doing so fairly tightly and so slowly and they will see people cycling as they make the turn. However, at this junction, there isn't really enough space for a driver to complete the turn and stop before the cycle/ pedestrian parallel crossing which is why I assume the sign is there.

You'll also note that there are some people cycling the wrong way or from strange directions - this is because the two stage left turn is less convenient (drivers don't have to put up with it) which means people don't all behave in accordance with the rules. Pedestrians do have to cross the cycle track which I know is a concern for visually impaired people (although the zebra does afford priority) and the refuge between the track and the carriageway is narrow. Much of this is down to the space being dominated by motor traffic.

I'd recommend reading posts on this type of junction from David Hembrow and Mark Wagenbuur. You might also like an older video of mine showing a simultaneous green for cycles by way of a contrast;

You can also catch up with Part 1 and Part 2 of this series.

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