Junction design and interactions
Getting junction design right is key. Junctions are places of interaction among street users and provide important place and movement functions.
Junctions serve as hubs of accessibility and surveillance, making them prime locations for public amenities like shops and transportation stops. The interactions between different street users at junctions underscores the importance of balanced design to harmonise both functional and movement aspects.
A significant number of road traffic incidents involving cyclists and pedestrians occur at junctions. It is essential to separate and protect their movements from vehicular traffic, especially at busier intersections.
Junction placement
Effective junction design is supported by the strategic placement of surrounding buildings. The space and buildings around junctions can create landmarks and assist in wayfinding.
Prioritising building layout also informs subsequent junction design as junctions are tailored to fit available space constraints.
The spacing of junctions should align with the scale and type of urban blocks, with smaller blocks necessitating more frequent junctions. This enhances pedestrian and cyclist permeability while diffusing traffic impact over a broader area.
Junctions should be designed to prioritise the safety and comfort of active travel movements without undue delay or deviation.
The design of junctions should consider the speed and volume of motor traffic. Where traffic volume is higher, it is likely that a junction will need to be signal controlled to enable separation in time or space between active travel and motor vehicle movements.
The types of cycle facilities at traffic signals are provided in Cycle Infrastructure Design (LTN 1/20), which gives further detail on their application and appropriateness. These are:
- cycle bypasses
- separate cycle phases
- cycle and pedestrian-only stage
- hold the left
- two stage right turns
- cycle gate
- early release
- advanced stop lines
Protected junctions
Protected junctions, including CYCLOPS (Cycle Optimised Protected Signals) junctions, are increasingly being implemented to entirely separate the movements of all modes of transport within the junction. This approach reduces the likelihood of conflicts and simplifies the operation of the junction into fewer stages, resulting in a more efficient traffic flow.
