This major project began in February 2012 with the objective to rehabilitate two major sewer trunk mains, one beginning in the suburbs leading to the north of the city and one starting from east of the Hume Freeway and heading to a pumping station in the centre of the city.
Andrew Craig, Albury City Council Contracts Coordinator, said “The smaller diameter main, first constructed around 100 years old ago, was suffering from gas degradation ranging from severe surface wear to complete loss of structural integrity. The larger diameter main is approximately 40 years old and had suffered from gas degradation ranging from surface wear to loss of structural integrity on two northern sections.”
Kembla Watertech’s extensive product offering allows the flexibility to offer the most appropriate lining methodology to suit the diameter, flow rates, time constraints, and geographic location of the pipeline requiring rehabilitation. In this instance, an expanding spiral liner using Kembla’s SWP DiaFit lining system was deemed the most appropriate solution.
Kembla Watertech’s DiaFit Project Manager, Damian Barnett said, “In total we rehabilitated nearly 5 km of sewer in Albury, including sections underneath the Hume Freeway and the Sydney to Melbourne railway line.”
Diameters relined as part of this project ranged from 300 to 600 mm, with the longest section being 180 m of 600 mm diameter pipe. A number of different spiral lining profiles were used to meet all design requirements.
Two major hurdles for the team were the traffic and the weather. A joint strategy between Kembla Watertech and Albury City Council was put into place to overcome these issues. Most of the project work was conducted at night to alleviate traffic disruptions, given that over 4 km of the sewer mains were located in the middle of the main road in Albury’s CBD.
Albury also recorded some of the heaviest winter rainfall ever experienced in the city while the works were being carried out. One of the benefits of the DiaFit system is that it does not normally require bypass pumping during installation. This minimises lost productive days due to wet weather and heavy infiltration.
Kembla Watertech’s DiaFit lining method allows sewer flow to be monitored via a plug and release method during installation, and neither the equipment nor the liner needs to be removed from the sewer at any time.
Key achievements during the project included the lining of two consecutive 300 mm diameter pipes located underneath a large commercial building. Severe gas degradation left the sewer with no invert and in some places no original pipe. Albury City Council was unable to use other contractors’ methods to successfully repair the pipes due to the great risk of collapse. Council was even considering the possibility of digging and laying a new sewer line when Kembla Watertech’s experienced DiaFit team devised a method to successfully conduct a CCTV survey.
“A CCTV camera boat was deployed to investigate the viability of lining such a dilapidated main and to confirm that adequate cleaning had been successful,” said Mr Craig. “This method was then used to view and guide the installation of the liner and reline the pipe.”
By successfully completing this project, Kembla Watertech has once again proved it is a company that can implement pipeline renewal solutions that succeed in the majority of conditions. The highest of safety and community standards were met on this project, with no lost time, injuries or complaints from the public recorded.
On behalf of Albury City Council, Mr Craig congratulated Kembla Watertech’s DiaFit team, saying “As this is the largest and most complex contract ever awarded by Albury City Council, Council would like to pass on our congratulations to Kembla Watertech in completing the contract in a timely manner, while recognising the professional staff that installed the liners.”