The northern section of Brussels’ long-delayed Metro 3 project could take at least a decade to complete if the works are ever restarted, according to the construction consortia involved in the tender process, as reported by Bruzz.
During hearings held Tuesday before the Brussels Parliament’s special committee on Metro 3, representatives from the two candidate consortia described the future North Station–Bordet section as an "exceptionally complex" engineering challenge.
The warning further clouds the future of the controversial metro project, after the Brussels Government decided to suspend the second phase indefinitely in its coalition agreement.
'Six years is not realistic'
Pieter Schepers, bid manager at Besix, told MPs that the six-year construction timeline initially envisioned by the Region is unrealistic. "We think we will need ten years," he said during the hearing.
A rally and march to the Midi train station organized by the StopMetro3 collective, to protest against the metro line 3 project and its impact on the Palais du Midi and surrounding businesses, Friday 13 February 2026 in Brussels. Credit: Belga
That estimate means that even if Brussels were to relaunch the project after a decade-long pause – a scenario often mentioned in political discussions - the metro line would not be completed before around 2046.
Two consortia are currently still officially in the running for the project. One is led by Denys, while the other combines Besix and Jan De Nul.
'Like building cathedrals underground'
Despite competing for the contract, both groups delivered similar assessments of the technical challenges linked to the northern route. “I have thirty years of experience and I have never seen such a complex project,” Steven Van den Heede, manager at Denys, told the parliamentary committee.
Schepers used a similarly striking comparison: “We have to build cathedrals underground.” The main difficulty lies in Brussels’ highly layered underground structure, which has already complicated ongoing works on the first phase of Metro 3 between Albert and North Station.
The Metro 3 worksite. Credit : Belga/ Eric Lalmand
Unprecedented ground freezing
A major issue concerns the use of ground-freezing techniques needed to create waterproof underground walls before excavation work can begin.
According to the contractors, the freezing process would need to reach depths of up to 82 metres, something they say has never been attempted anywhere in the world.
The companies also stressed that the project relies heavily on highly specialised foreign subcontractors, particularly experts in underground freezing technologies.
