Vienna Valley Relief Channel – WSKE West

In order to adapt Vienna's wastewater disposal system to the growing demands of the population and to ensure the protection of the Vienna River (Wienfluss), a new relief channel is being built along the western Vienna Valley – the Wientalsammelkanal‐Entlaster (WSKE) West. The hydraulic objective of this structure is to relieve the Vienna River by reducing sewer discharges during heavy rainfall events. In addition, this will enable maintenance work to be carried out on the existing sewer system. The WSKE West crosses three geological zones and, due to varying subsoil conditions, places different demands on construction methods and procedures. The channel is being constructed in the vicinity of the Vienna River using a tunnel with a closed construction method with an internal diameter of 3.00 m. The collection channels on the left and right banks of the Vienna River are connected to the WSKE West via some 40 overflow chambers, so that overflowing mixed water is discharged into the new channel.