Multimodal Traffic Complex
A12 Londerzeel-Zuid
The Agency for Roads and Traffic (AWV) and the contractor group ViA12 have signed a public-private partnership agreement for the redevelopment of the Londerzeel-Zuid junction on the A12. Sweco, as the design office, is using its multidisciplinary expertise to make traffic at the on- and off-ramps safer, smoother, and more multimodal.
- Client
- ViA12
- Location
- A12 Londerzeel-Zuid
- Expertise
- Civil engineering construction, traffic & mobility, complex processes, strategic planning, urban management, climate adaptation and integrated water management
With the ‘Londerzeel-Zuid’ project, the appearance of the intersection will completely change. The A12 will be dug in and lowered. On top of it, there will be two bridges, one for local car traffic and one for cyclists and pedestrians. ViA12, a ‘temporary partnership’ of Jan De Nul Group and Willemen Group, will transform the current intersection into a safe junction with conflict-free on- and off-ramps.
The untangling of both active (cyclist, pedestrian) and hard (car) traffic flows fits within Flanders’ ambition to transform the A12 from Antwerp to Brussels into a full-fledged and safe highway with grade-separated crossings instead of the current level traffic lights. Along with solving the traffic knot, this is also a project of liveability and ecological connection.
Multidisciplinary Design for Liveable and Ecological Added Value
In 2023, Sweco supported ViA12 during the initial bidding phase and later in the BAFO (Best and Final Offer) phase of the procurement procedure. We are currently working on the final design and the environmental permit application. Once that permit is issued, the green light is given for the start of the works in the spring of 2026.
Due to the multidisciplinary nature of the project, various expertise within Sweco is involved in putting together this design puzzle: from civil engineering construction, traffic & mobility, and complex processes, to strategic planning and urban management, to climate adaptation and integrated water management.
Earlier design plans were refined to arrive at a more sustainable concept. This translates into, among other things, less material use and better water management in the project area. The user comfort for active road users also improves, partly thanks to a modified integration of the bicycle bridge.
Videos by Mode of Transport | Designed by Sweco – Splendid
Conflict-Free Traffic: Bridge Instead of Intersection
The A12 will be dug in so that it lies lower than today. Traffic that wants to enter or exit the A12 will use the new on- and off-ramps complex. A bridge (2×2 lanes) over the highway will be the conflict-free connection for local traffic between Londerzeel and Westrode (Meise). This allowing everyone to drive more smoothly and safely.
Safety and Comfort for Active Road Users
There will be a separate bridge for cyclists and pedestrians. This way, they can cross the A12 in complete safety and comfort. The bridge is 4.5 meters wide, allowing cyclists and pedestrians to safely pass each other. The slope of the bridge is 3.5%, so everyone can easily ride up the bridge. On the east side, the F28 cycle highway will be constructed in the project area, which will pass under the traffic complex through a tunnel.
Green-Blue Network
Green and water play a crucial role in the redesign of the project. There will be an abundance of planting and large, open buffer basins. After the infrastructural works, the area will be arranged in such a way that the native flora and fauna can recover and further develop.
These green and water-rich elements give the project a significant ecological added value. The buffer basins will be surrounded by native planting, which not only promotes biodiversity but also creates a beautiful, natural environment.
