Construction of main sewer using directional drilling for new public transport debot

Design

The existing Ruhrban depot was undersized and a new extension had been planned on the same site. Before this new-build project could be started, the current concrete sewers had to be diverted and their capacity had to be increased. As the sewers were situated 8 metres below ground level, we opted for directional drilling and concrete pipes with a steel core and a diameter of 800 mm. Part of the pipes were made of Polyethylene with an inner diameter of 300 mm. The various sewer pipes were connected to each other with precast concrete wells.

Excavating and building while the buses and trams keep running.

Every evening and night, the buses and trams were cleaned, serviced, refueled and prepared for the next day.  The work was also hindered by the presence of overhead lines above the planned route of the sewer. To avoid damaging the overhead lines and to safely perform our work, the overhead line grid was temporarily disconnected and diverted. The main challenge in this project was to schedule the work in such a way as to affect the bus and tram depot as little as possible. The continued drainage of wastewater from existing buildings was guaranteed by diverting it through a pumping station.