THE northern section of the HSL-South high-speed line in the Netherlands, which connects Amsterdam with the Belgian border, will close for three months in 2028 to allow major repair works to be carried out on four of the 10 defective viaducts. Trains are currently limited to 120km/h on the section between Rotterdam Central and Hoofddorp, which is designed for operation at up to 300km/h.
Infrastructure manager ProRail has confirmed that during the closure, IC Direct, EC Direct and Eurostar services will be diverted via Leiden and The Hague. Until then, current operating arrangements, including the speed restrictions, will remain in place. The northern section of HSL-South opened in October 2006.
Speed limits were imposed on the line in July 2023 following the discovery of cracks in 10 viaducts located between the northern portal of the 8.7km Green Heart tunnel and the junction at Hoofddorp where HSL-South joins the conventional network. The structures were found to be “too light” to handle 300km/h operation, with cracking caused by a combination of weak ground conditions, typical for the west of the Netherlands, and the forces exerted by passing trains.
The line is expected to remain subject to significant speed restrictions until at least 2031.
Repair works are estimated to cost around €580m. ProRail says it is aiming to reduce disruption by progressively restoring higher speeds section by section as works advance from south to north.
In September 2025, ProRail signed a six-year framework agreement worth €25m with three engineering companies to design repair solutions for nine of the 10 viaducts affected. The work began immediately due to the urgency of the situation, and designs are expected to be completed by the end of 2026. The contract includes options to address any additional infrastructure issues and to implement measures intended to avoid further corrective interventions for up to 80 years.
The 10th viaduct will be handled under a separate programme.
Legal proceedings
The Dutch Ministry of Infrastructure launched legal proceedings in August 2025 against construction consortium Hollandse Meren, which it holds responsible for the design and construction faults. The consortium includes Boskalis, Ballast Nedam, Volker Wessels Stevin and Vermeer. The ministry is seeking compensation not only for repair costs but also for wider damages, including compensation paid by operators to passengers for delays and cancellations.
Thierry Aartsen, caretaker state secretary for public transport and the environment, says the government does not want taxpayers to bear the cost of the failures and expressed hope that the consortium would cooperate to reach a settlement. Compensation claims from high-speed operators Netherlands Railways (NS) and Eurostar are estimated to run into several tens of millions of euros, although the final figure has yet to be determined.
