Skip navigation

Sewer Heidelberg-Ziegelhausen, Wilhelmsfelder Straße

The suburb of Ziegelhausen is located in a valley near Heidelberg. A brook flows through it in the direction of the River Neckar. The inhabitants of Ziegelhausen had in some cases, their own domestic clarification plants, which were no longer fully functioning. Some of the waste flowed into the brook. A collector was necessary, to which the individual houses could be linked up. The most suitable course for its route was on the valley floor, partly under the brook. The application of heavy construction equipment for laying the collector by cut-and-cover could not be contemplated on account of the tricky local conditions. As a result, the City of Heidelberg decided to execute the project by mining means. The subsoil consists of loose sand and sandstone plates with an edge length of up to 80 cm, furthermore, fast-flowing groundwater and underground water are present. The total driven length of 830 m was split up into 4 part-sections, 2 of just fewer than 100 m, 1 of 210 m and 1 of 430 m. The sections partly run in a spherical curve with a radius of approx. 300 m. The columns have an overall difference in height of 50 m with an incline of up to 9 cm/m. 3 m long reinforced concrete jacking pipes were laid . An AVN 1200 tunnelling machine from the Herrenknecht GmbH, which is particularly suitable for long-section headings, because the hydraulic aggregate is installed directly behind the machine, was used. Only the electric power supply and the flushing conveying lines have to be carried. On account of the tricky soil conditions, a rock bore head was applied. The sections were driven accurately using the curve measuring system from the firm VMT. The domestic connections DN 150 were also completed by mining means. A specially developed domestic connection machine Type HCMP from the Herrenknecht GmbH was used. The machine was set at the connecting point in the collector, where it was braced. It then bored from the jacking pipe in the direction of the target pit. The difficult soil conditions were mastered through advance grouting with cement and bentonite and a suitable rock bore head.


  • Country: Germany
  • Region: Baden-Württemberg
  • Tunnel utilization: Utilities
  • Type of utilization: Sewage
  • Client: Stadt Heidelberg
  • Contractor: K-Boringen, Roland Spezialbau
  • Main construction method: Trenchless
  • Type of excavation: Pipe jacking
  • Lining: Reinforced concrete pipe
  • No. of tubes: 1
  • Tunnel total length: 830 m
  • Cross-section: Sewer DN 1200, domestic connections DN 150
  • Construction start/end: September 1995 to October 1996