Better Junctions

Want to know more about Transport for London's Better Junctions scheme? Click here.

Well over 70% of serious injury or fatal collisions happen at major road junctions in the capital each year – a sobering statistic. A major cause of these injuries and deaths is left turning motor traffic, known as ‘left-hooks’ (referring to vehicles crossing a cyclist’s path).

Advanced stop lines (ASLs), which were first implemented with the intention of making cyclists more visible and reducing the risk of conflict with motor vehicles, do not eliminate the risk of left hooks. ASLs also can’t eliminate the risk of ‘shunts’ (when a vehicle hits a cyclist from behind), and ‘right-hooks’, which represent the next biggest threats to cyclists. Of course, one of the problems with ASLs is down to driver behaviour – research has suggested between 9 and 54% of motor vehicles encroach on ASLs by at least 25%. But the main problem is that ASLs can’t protect cyclists from being hit by motor vehicles – and they do absolutely nothing to help cyclists arriving when traffic lights are green.

The same issue applies to TfL's new "Early Release" ASLs. Here, a cycle-specific light gives those in the ASL a few seconds to get ahead and across the junction before any turning traffic. These have some value on the arms of junctions where traffic is held the majority of the time - so the vast bulk of people cycling end up in the ASL. But they still offer no protection for those riding up to lights on green. And of course both ASLs and Early Start ASLs don't feel safe or comfortable enough to entice anyone who doesn't currently cycle to start doing so.

So what is needed? Junctions that separate those cycling in time and/or space from those driving, junctions that feel safe and comfortable to navigate. LCC is a strong supporter of British Cycling's "Turning the Corner" campaign to change the law to enable "give way at turn" design and behaviour. If this campaign succeeds, then we'd see a lot more junction designs that resemble European approaches.

Until that comes along, TfL's best designs incorporate their "Hold The Left" approach of separating left-turning motor vehicle traffic from cycle flows with an extra signal. But these junction designs use up a lot of space and often introduce extra signal phases, cutting motor vehicle traffic capacity - which TfL are generally still far too scared of.

LCC activists also have a version of "Hold The Left" we think has real potential to improve on TfL's designs. The "Cycle Segregated Junction", versions of which are illustrated in diagrams below, has been championed by us for years. Variants of this junction exist for many types of junction.

Major junctions

Stage 1 and 2

In Stage 1 of the above diagram, traffic lights are red for traffic turning left and right, and green for traffic — drivers and cyclists — going straight ahead.

East and west-bound traffic can go at the same time and pedestrians can cross at the same time as the ahead traffic.

In phase 2, north and south-bound traffic can go. Result? No risk of traffic turning across the cyclists’ path — therefore no left-hook collisions. And because cyclists and pedestrians get the same amount of ‘green time’ as motor traffic, it’s more efficient for everyone.

 

Stage 3 & 4

In Stage 3, the traffic lights go green for north and south-bound left turns, and east and west-bound right turns. All this traffic can go at the same time.

And finally, in Stage 4, the traffic lights go green for north and south-bound right turns, and east and west-bound left turns. 

 

Crossroads where primary and secondary roads meet

Phase 1-2

On Stage 1, all north and south ahead traffic goes. At Stage 2, rights and lefts go together, and eastbound cyclists can go.

Phase 3&4

 At Stage 3, southbound rights and lefts go together, and westbound cyclists go ahead. During Stages 2 and 3 east and westbound pedestrians can cross safely at the same time. At Stage 4, east and westbound traffic can go. 

This model allows the same number of phases as currently, but gives more time for pedestrians and cycles to cross.

 

This type of junction can be seen at many locations in London, such as Ludgate Circus.

 

T junctions

 T junction

 

Duriring Stage 1, all straight ahead east and west bound traffic - vehicles, cycles and pedestrians - can go. Turning motor traffic is held; cyclists turning right do the first stage of a two stage right turn.

In Stage 2, right turning southbound traffic can go - cycles making the second stage of their two stage right turn.

T stage 3 of 3

During Stage 3, left turning southbound motor traffic, right turning eastbound traffic (including cycles), and cycles turning left to go west can all go at the same time.

T junctions of major and minor roads

 T junction major minor

 

During Stage 1, all east and westbound traffic goes. At Stage 2, right turning traffic goes (cyclists making the second stage of a two stage right turn). 

 

Stage 3 & 4

During Stage 3, traffic turning left into the minor road can go, and east and west bound cyclists with a bypass for left turning cycles. At Stage 4, motor traffic turning east or west onto the major road can go.

 Harford Street and Mile End Rd is an example of a junction like this:

 

Left and right turns
Left and right turns

Here are the left and right turns in more detail. Cyclists turning right will do so ahead of the pedestrian crossing, so there is no conflict.

For cyclists turning left: if a left filter for cyclists is installed, the flow will usually be fairly low - most cyclists go straight ahead, with only around 20% turning left. A mini-zebra across the cycle lane can be installed to enable pedestrians to cross. If the pedestrian flow is high it is possible to install traffic lights for pedestrians to cross, but in most cases this won't be necessary.