Copenhagen M4 metro extension to halve emissions
Copenhagen is taking another bold step in shaping the sustainable city of the future. The Copenhagen M4 Metro Extension will deliver two new metro stations extending the network into Nordhavn, one of the capital’s fastest-growing urban districts. The extension supports Copenhagen’s public transport system while supporting the city’s long-term vision for sustainable urban development.
A key ambition of the project is to achieve a 50 percent reduction in carbon footprint compared to the baseline established during the previous phase of the M4 line. This target is being pursued through integrated structural and geotechnical design, climate risk assessments, and the application of nature-based solutions wherever feasible. By embedding sustainability at every stage of the design process, the project aims to set new standards for low-carbon infrastructure delivery.
Strengthening connectivity and creating social value
The project is delivered through an Early Contractor Involvement (ECI) model, enabling strong collaboration from the outset. Ramboll and Cobe are engaged as consultants under the contractor, MT Højgaard Danmark, while maintaining a close and collaborative relationship with the client, Metroselskabet. This delivery model allows early alignment on design, cost, constructability, and sustainability objectives, making collaboration a central driver of the project’s success.
The collaboration began in October 2025 and will continue until June 2027, with an option to continue together into the next phase of detailed design and construction into completion in 2030. Ramboll, is drawing on its global expertise to ensure strong civil engineering capabilities across all phases of the delivery.
Beyond expanding transport infrastructure, the M4 extension aims to create social value, strengthen urban connectivity, and set new benchmarks for sustainable metro development. The project will deliver a resilient and future-ready transport solution that benefits both local communities and the wider city.
"The M4 project is a great example of what we can achieve when we position early with a multidisciplinary and geographically diverse team and the right partners to enable winning the design and build contracts, based on a form of collaboration we believe in."
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