Remuera branch 1 & 2 rehabilitation 2009

Pipeline rehabilitation has presented major challenges to owners and contractors as cities have developed. This paper illustrates how Watercare overcame these challenges to carry out repairs to their Remuera Branch 1 & 2 sewers. These sewers were built in 1910s. A century later, they were approaching the ends of their lives. Although they had been built under farmland, the districts they run through are now occupied by some of the most expensive real estate in NZ, and St Kentigern's School. These site factors dictated that a trenchless rehabilitation method would have to be used for the rehabilitation of both sewers. CIPP (cured-in-place-pipe) lining was identified as the most appropriate method for rehabilitation of the egg shaped sewers. A 250 litre /sec flow diversion was required to allow the use of this rehabilitation method, and a 17m deep temporary shaft had to be drilled in the grounds of St Kentigern's school to enable the lining installation to proceed. The contract team completed the work successfully with minimal inconvenience to the residents and commuters of Auckland’s eastern suburbs. The Branch 1 &2 sewers are now be expected to give at least another 100 years service.