Objective:
To encourage drivers to respect the 30 km/h speed limit using a simple, innovative method that avoids the drawbacks of traditional traffic-calming measures.
The Intervention:
- Two short traffic islands are placed 270 cm apart, preferentially mid-block.
- Though the gap appears narrow, it is perfectly fine for buses and large trucks due to sloped, driveable edges and a total clearance between bollards of 312 cm.
- This setup subtly “nudges” drivers to slow down. Compared to speed bumps or Berlin cushions, we observe a speed profile with less braking and accelerating, which results in reduced noise pollution and lower fuel consumption. In addition, the system does not generate vibrations for nearby residents.
Project Phases:
The system went through several testing phases, ranging from short sessions at 10 locations in two Brussels municipalities to 2-3 week trials with continuous speed monitoring and a survey of residents and street users. Based on this, Koekelberg became the first municipality in the Brussels Region to decide to make the Nudge30 intervention on Vande Sandestraat permanent as of September 2025.
Results:
This test in Schaerbeek clearly shows the speed-reduction effect of the Nudge30 system. Speeds were measured over two weeks, with and without Nudge30 halfway along the street segment. Only freely moving vehicles were included in this graph (not preceded by another vehicle in the past 5 seconds).
Learn more:
- A video from the Stakeholder workshop providing an extensive report of the testing phase.
- The pptx presentation used at the workshop.
Support:
The project was supported by Brussels Mobility.
