Austrian state railway ÖBB has submitted its plans for the quadruple-track expansion of the main line of Vienna's suburban rail (S-Bahn) network from Meidling to Mödling for environmental assessment. The line serves around 400 trains per day. The goal of the project is to separate faster REX regional services from local S-Bahn services in order to create more capacity for both. This will allow the S-Bahn to run every ten minutes and stop at two new stations. The plans to modernise the line have been developed over the last three years by ÖBB and the local authorities involved and have now been submitted to the Federal Ministry for Climate Action, Environment, Energy, Mobility, Innovation and Technology (BMK) for a mandatory environmental impact assessment. The BMK is expected to give its approval by the end of 2025 so that construction can begin in 2026. The project also includes the construction of two new stations and the modernisation of four existing stations. It envisages a total investment of €2.4 billion by 2034. Completion of the Vienna Meidling – Liesing section is planned for 2032, while the Liesing – Mödling section is scheduled for completion in 2034.
