After the awarding of the renovation of the Noordtunnel (A15), the tender for the renovation of the Drechttunnel (A16) was published on May 15, 2025. The Drechttunnel is over 45 years old and needs a significant renovation. Besides the lighting, which was replaced in early 2025, all technical installations will be replaced.
The structure and asphalt will also receive an upgrade. Maintaining during the execution and the maintenance until 2039 after the renovation of the tunnel is also part of the assignment. The contract for the Drechttunnel and the 2nd portfolio tunnel renovation in South Holland is expected to be awarded in the spring of 2026.
Bundling Tunnel Renovations in Portfolio
Rijkswaterstaat works with a portfolio approach, which stimulates a new way of collaborating with the market and contributes to more continuity and innovation. With this approach, we optimally deploy the available capacity and knowledge from both Rijkswaterstaat and market parties. This approach also allows us to gain learning experiences across projects and apply them to future tunnel renovations.
The tender for the renovation of the Drechttunnel offers the contractor the opportunity to later also carry out the renovation of the Sijtwendetunnel (N14). Rijkswaterstaat will award the follow-up assignment through a negotiation procedure without prior announcement. This will happen within 3 years after the tendering of the 1st assignment of the portfolio.
Understanding Phase
Renovation projects are less predictable and therefore require a different approach than construction projects and regular maintenance. Therefore, Rijkswaterstaat has chosen to add an understanding phase after discussions with the market.
In this phase, the selected contractor and Rijkswaterstaat will work closely together to further investigate the renovation challenges and jointly understand the approach, after which the final pricing will take place on risky components.
Tender Planning
Interested contractors (combinations) can register for the tender until June 18, 2025. The contract is expected to be awarded in the spring of 2026, after which the understanding phase begins. The execution of the renovation is expected in 2029-2030.
About the Drechttunnel
In the early 1970s, there were increasing traffic jams at the traffic bridge between Dordrecht and Zwijndrecht. Therefore, the decision was made to build a tunnel, resulting in a widened A16 and new connections to the highway. This allowed the business parks in Dordrecht and Zwijndrecht to develop fully. The construction of the tunnel started in 1972 and it was put into use in 1977.
The Drechttunnel was designed with 4x2 lanes, divided over 4 tunnel tubes, and is 596 m long towards Rotterdam, and 538 m towards Breda. The traffic tubes are separated by a central tunnel canal.
Collaboration with Market and Environment
Innovation, efficiency, craftsmanship, and trust are needed to carry out these tunnel renovations and the largest maintenance task ever on our infrastructure. And an environment that adapts during the execution of the tunnel renovations.
Therefore, Rijkswaterstaat works closely with municipalities, provinces, safety regions, and other stakeholders. In the run-up to and during the work, we inform residents and road users about the expected inconveniences and alternatives.
Major Renovation for Multiple Tunnels in South Holland
Many tunnels, viaducts, and bridges in the Netherlands are due for replacement. As part of the national renewal task, Rijkswaterstaat will renovate multiple tunnels in South Holland in the coming years. Within the Tunnel Renovations South Holland Project, we ensure that the Noordtunnel (A15), Drechttunnel (A16), Beneluxtunnel (A4), Second Heinenoord Tunnel (A29), and the Sijtwendetunnel (N14) remain safe and available in the future.