EQUANS participates in the renovation of the longest tunnel in Belgium and designs the city of tomorrow.
Smoother traffic, improved user safety, less greenhouse gas emissions… It’s true: the city of tomorrow will be connected, sustainable, and safe. EQUANS is taking the lead in the Leopold II tunnel, a 2.6-km long tunnel in Brussels, and working to improve the infrastructure thanks to a combination of different techniques.
Emblematic tunnel
‘Leopold II’ is the tunnel connecting the Koekelberg Basilica with the inner ring road of Brussels. Every day, some 80,000 inhabitants of Brussels and commuters pass through, whose safety must be guaranteed. Unfortunately, after 30 years of good and faithful service, the structure and the electromechanical installations showed many signs of ageing, which raised fears of a possible closure, with the disastrous consequences this would have for mobility in and around Brussels. For this reason, EQUANS has been working on the modernisation of this tunnel since May 2018 on behalf of Brussels Mobility, in collaboration with BESIX and Jan De Nul, which are in charge of construction and road works.
Maximum safety
Over 80% of all electromechanical installations are safety systems so that the tunnel complies with the latest safety standards. This includes, for example, 250 cameras, which are managed and controlled by EQUANS to ensure the safety of users and technical teams. These are, on the one hand, smart cameras that automatically detect fires, pedestrians, and accidents and, on the other hand, cameras that play a role in the management of emergency exits and technical premises. In addition, ANPR cameras will map traffic flows as well as emissions and speeds. A fully redundant fibre-optic network consisting of 35 km of fibre-optic cables will support the transmission of the high-definition images. All electromechanical systems will be linked to a SCADA system, a centralised technical management system that will enable Mobiris (the ‘Brussels Mobility Centre’) and our maintenance teams to remotely manage the equipment and intervene in the event of dangerous situations or breakdowns in the safety systems.
Firefighting
In terms of fire protection, the former safety system is being thoroughly expanded and strengthened. Fires in the tunnel can be detected very quickly by the smart cameras that automatically detect smoke and thermal fibre-optic cables. After a fire has been detected, over 10 powerful extractor stations are ready to extract the smoke together with some 80 jet boosters so that the people in the tunnel can leave safely and the fire brigade can get to the scene of the fire. In order for an evacuation to proceed as quickly as possible, 17 new emergency exits will be added to the 13 existing ones. All emergency exits will be equipped with an automated emergency call system, flashlights, audible signals to attract attention, and overpressure systems. In order not to allow additional vehicles into the tunnel, it can be closed off by means of barriers at the tunnel entrance and inside the tunnel.
Comfort, design, and ecology
For greater driver comfort and safety, the signalling equipment will be revised with the installation of dynamic information panels. LED lighting will also be installed inside and at the tunnel entrances. This new lighting can adapt to the brightness from the outside thanks to the sensors located outside the tunnel. It will also give the structure a more modern appearance and reduce electricity consumption by over 70%. The air quality in the tunnel will be monitored by approximately twenty air quality sensors. If the threshold values are exceeded in certain areas of the tunnel, there is a complex regulation system that allows eighty jet boosters in the tunnel to blow the correct amount of fresh air through the tunnel.
Logistical challenge
Our teams are currently working day and night to complete the final phase of this gigantic construction site. The end of the renovations is planned for the spring of 2022. From that point on, our teams will be in charge of maintenance for 25 years. Throughout the entire duration of the works, EQUANS has taken measures to limit the impact on traffic and locals as much as possible. Other projects of this type are expected to take place in the capital in the coming years. Many tunnels in Brussels are indeed in need of improvement. The goal? Keeping Brussels, as the heart of Europe, in the spotlight as a city with sustainable mobility that improves citizens’ quality of life.
