HOBAS Pipes Jacked 40 Meters beneath the Gardens of Prague Castle

After the successful completion of the Prague Sewer Project COIII in 2012, for which more than 1 kilometer HOBAS GRP Gravity Pipe DN 1800, SN 12500 has been installed in a tunneled duct, a follow-up project utilizing HOBAS Jacking Pipes was launched toward the end of 2013. Since the sewer was to be installed in 40 meters depth beneath the gardens of Prague Castle, jacking presented itself as sole solution for pipe installation. Company Energie – stavební a báňská a.s., the same contractor who had already been contracted for COIII was assigned for the job. Due to the light material and good experience with HOBAS, a total of 207 meters HOBAS Jacking Pipes De 1940, SN 50000, PN 1, were utilized on the project. Poor in situ soil conditions posed a challenge to the contractor for the so-called Letná-shale when crushed and mixed with water turned into sticky sludge that presented a challenge to the pumps. Apart from a resulting slight delay, installation progressed well, not least thanks to timely deliveries and the easy handling of HOBAS Jacking Pipes. As usual, HOBAS Experts shared their experience and offered advice from inception to completion.