Implenia To Build District Heating Tunnel Under the Elbe
In December 2021, Implenia was awarded a contract by project owner Wärme Hamburg to build a tunnel under the River Elbe for Hamburg’s new district heating network. The project is worth around E72 million euros, and Implenia is responsible for the detailed design and basic construction of the tunnel and the district heating pipe, as well as for planning and installing the required operating technology.
Digital 3D planning is being used to plan and optimise – technically and financially – the complex special foundations, tunnelling, civil engineering and pipe laying work. This 3D-model of the start shaft at Finkenwerder superimposes all the stages of work, including the above-ground construction site equipment for collision control
Credit/Quelle: Implenia
Implenia has been working on the design since October 2021 (Phase 1). It has now been given the contract for the further planning and construction, commencing at the start of 2022 (Phase 2).
District heating generation in Hamburg is set to change fundamentally over the next few years. Central power plants north of the Elbe are being decommissioned and replaced by an efficient and decentralised district heating network. Climate-neutral waste heat is being taken from various sources, including a waste recycling plant, the wastewater heat pump of a sewage treatment plant and other energy-intensive industrial operations south of the Elbe. The heat will be combined in a storage
circuit and brought to the required temperature. A new Elbe tunnel is needed to reach consumers north of the River Elbe. This will be drilled about two kilometres west of the Elbe Tunnel on the A7 motorway, from Köhlfleethafen near Finkenwerder to the Elbchaussee on the north bank.
Implenia’s Special Foundations department is creating diaphragm walls up to 42 m deep for the start and end shafts. A tunnel boring machine will drill a 1.16-km-long tunnel between the two shafts with a diameter of around 4.5 m and lined with precast concrete sections. Access and operating equipment will be built into the two shafts for future use. The contract also includes installation of the technical building equipment and the district heating pipe with supply and return flow. The work should be completed in the first quarter of 2025.
