So last week, I looked at ‘partially protected’ turns at a crossroads and this week, I thought it might be helpful to look at a T-junction variant.
The reason I looked at the crossroads was that on the side streets, there simply wasn’t space within which to build cycle tracks which would allow a fully protected junction and so people cycling into/ out of the side streets would have to join/ leave the carriageway.
Where we have one side street with the same issue, then we’ve a couple of options, but here’s a layout;
As before, cyclists move at the same time as pedestrians. Cyclists turning left will be held on a red low level cycle signal (LLCS) until the walking/ cycling stage ends and they will get a green just before side road traffic is released.
On the other side of the junction, you will see a little right turn ‘pocket’ inset from the main cycle track – for right turning cycle traffic of course. In the same way as people could turn right from the cycle track in last week’s example, people could turn right from the pocket at the same time as the cycle traffic.
People cycling from the side street would just turn left for the northbound cycle track and cycle to the far side and just turn right to head southbound. For any cyclists waiting at the right turn pocket, people leaving the side street would pass behind them. If it was a popular right turn, then space becomes a little more complicated and it may be that southbound cyclists have to have signals to allow people out of the side street (but this is quite heavy engineering for cycle traffic – circled red below);
This variant complicates matters a little, but it means that southbound cyclists are held on a red when the side street runs on green. This is of course far less convenient for cycling and perhaps overly cautious.
One other slight tweak of the first layout about can be seen on CS6 on Farringdon Road in London (which is not quite on Google Streetview). The right turn pocket has the stop line to the right of the cyclist and people coming from the side road have a little give way point as they join the southbound (in my example) cycle track;
The stop line is in an unusual position, but it’s still intuitive in my view – here’s a still from a video I made of this part of CS6;
The thing I’m tending to see with designs such as these is that the pedestrian crossings are often being installed as staggered 2-stage variants and often only on one arm of the main road. I’ve shown single stage and crossings on both main road arms. While I acknowledge the whole “don’t make perfect the enemy of good” argument, we should be pushing for single stage crossings; especially if the provision of cycle tracks upset the pedestrian desire lines as they sometimes do.
There are clearly lots of different ideas and elements at play and so it is important to work out where the main cycle traffic flows will be. If we have heavy movements from a side street to a main road, then we may well be looking at a different signalling arrangement than where cycle traffic is generally on the main road.