The province of South-Holland wants to improve comfort and flow for cyclists in the province through the bicycle program. At intersections regulated by traffic lights, there are opportunities to improve bicycle facilities. DTV Consultants mapped this out for the province. Measures have been devised for twenty intersections on provincial roads frequently used by cyclists.
The province of South-Holland currently manages approximately 130 intersections controlled by traffic lights; approximately half of these have bicycle crossings. Rolf Willems, infrastructure consultant for the province of South-Holland: “To stimulate cycling, the facilities must be in order. Comfortable cycling routes, on which it is easy to cycle at a constant speed, are the norm for us. We also want to focus on the possibilities of smart mobility. Because DTV Consultants’ extensive expertise in both cycling and the field of traffic lights, it was a logical choice for us to have them address this issue.
To determine the most effective measures, DTV has:
- done research into possible improvements for cyclists at intersections controlled by traffic lights.
- identified the twenty most frequently used intersections on provincial roads by cyclists. Based on data from the Quality Control Centre. These findings were verified in discussions with experts from the province.
- revealed which facilities are already present for cyclists at these intersections.
The result of the study is a matrix containing the possible measures for each intersection. The 34 identified possible measures can be divided into:
- Detection: Better detection of cyclists, for instance by anticipating traffic lights;
- Information: Inform cyclists regarding red or green light. To possibly influence behaviour;
- Optimising: Prioritise cyclists in the traffic light control or change sequence of handling;
- Safety: Anything that will improve road safety for cyclists;
- Comfort: Making intersections more comfortable for cyclists, for example by literally giving cyclists room to manoeuvre;
- Innovation: Innovative measures, with different results or goals.
Willems: “We considered the proposed measures. We looked at the benefits for cyclists, but also at the availability of short- and long-term budgets. Eventually, we divided the measures into three stages: some measures will be implemented immediately; others will first be trailed at a single intersection or the effect of the measure is calculated in depth before deciding on broader deployment. The remaining measures are entered in the cycle of regular maintenance at the intersections and the TCS’s.
Explanation of the measures:
Detection loops can be applied for both application and extension of green. A variation on a normal detection loop is an 8-shape loop. This creates more angles, making the loop more sensitive and therefore it detects cyclists better.
Remote detection loops
Remote or distant detection are loops located at a certain distance (preferably more than 25 meters) from the stop line. These loops detect cyclists earlier and therefore request a green light sooner or hold the green light to reduce the likelihood of cyclists having to stop.
Directional detection loops
Directional detection loops are two almost overlapping loops. Based on the order of detection these loops determine in which direction a cyclist is moving. Cyclists who move away from the traffic light, therefore, are filtered so that no false requests or prolongations are made.
With a thermal camera, it is easy to distinguish individual cyclists and a group of cyclists. Using a thermal camera, for example, priority can be given to cyclists when they are with a (large) group.
Bicycle Light Information Panel (BLIP)
When an intersection can be crossed in two directions on each arm, there are different ways for cyclists to cross the intersection. A BLIP informs cyclists about which of the two intersection routes is faster, namely to the left or to the right.
Follow Green is a system of (LED) lights along the bicycle path starting 25 metres from the stop line (in the detection area). All of the LED’s light up as soon as the traffic light turns green. Starting from the LED furthest from the intersection they switch of one by one. When the last light goes dark, the light turns red. Cyclists, therefore, know that as long as they are cycling next to a lit LED, they are going to pass through the green light.
Evergreen is a similar measure to Follow Green. The difference is that Evergreen indicates where and at what speed cyclists have to travel to make it to green, even during red. Follow Green only provides this information during a green light. Same as Follow Green, Evergreen provides the information to cyclists by a LED line. However, over a longer distance (200 metres).
Favourable phase sequence for cyclists turning left
By giving the users of an intersection green in a certain order, cyclists can make several crossings without having to stop or with a much shorter wait.
1st green after conflict
A form of prioritising is to give cyclists green light after every conflict. This means that as soon as a request is made by a cyclist, the direction they are going in will be given a green light after the conflicting direction is dealt with and evacuated. This measure must always be investigated first to determine whether it is still acceptable for other traffic.
Adjusting the lane layout
By adjusting the layout of the lanes or adding lanes, the number of cyclists’ conflicts can be adjusted.
Free linking between bike directions
In the case of a free link, the bicycle direction that is already green (and has no conflicting requests) remains green as soon as an application is made for a different direction. Cyclists in the direction that needs to become green can pass crossing after crossing without stopping.
Bike scout is a visual warning on an unregulated crossing that draws motorists’ attention to approaching cyclists who have priority. This measure reduces the chance of cyclists crossing the intersection unexpectedly in front of other road users.
Widening set-up space
The widening of the set-up space provides greater comfort for cyclists in the set-up and reduces obstruction for oncoming riders.
When using the ‘banana’, the positioning space also increases, but it is done by reducing the shoulder island in the bend. This measure makes more effective use of the available space. The disruption of parked cyclists for other cyclists as well as motorists will be minimized as a result.
With the ‘cone’, the space of a double-crossing is used more effectively. The dividing line in the middle is laid slanting, which provides more room to set up on both sides of the crossing. As cyclists cycle away at different speeds, less space in width is needed.
Shifting bicycle infrastructure
Moving a bicycle path can make a route more direct or safer. More direct bicycle paths reduce travel time for cyclists or make the situation more credible.
iTCS in combination with a bike app
An iTCS is an intelligent traffic control system that communicates with road users. The extra features of an iTCS can be used to inform, prioritize or optimize. Because an iTCS communicates with road users, road users can use an app to request green light at the iTCS.