The NSW Civil Contractors Federation (CCF) Award Category 1 (Project value up to $1 million) has been awarded to Interflow for the delivery of the Sydney Water Double Bay ovoid sewer rehabilitation project.
The project involved the renewal of a large size ovoid shaped sewer in Sydney’s harbour side suburb of Double Bay. Because it was an ovoid shape, rather than a circular sewer, Expanda Pipe was not suitable. The sewer was extremely deep in an area with a high water table, meaning that the CIPP liner did not have enough strength to meet Sydney Water’s design specification.
The solution was identified as a fibreglass reinforced liner from Germany, cured by UV light rather than hot water, which was strong enough to meet design requirements.
However, to meet the requirements of this project, it needed to be thicker and heavier than the manufacturer had previously supplied for this size anywhere in the world. It also had to be installed to 14 metres depth in continuous lengths up to 185 metres, so the team worked with the manufacturer to develop suitable installation procedures for the project and then carried out training and trial installations at our Girraween workshop.
Most of the access chambers were located in private properties where excavation was not practical, one being inside an underground car park for an apartment block. Good planning and community relations was therefore an essential part of the project.
Armed with a well considered solution, a solid plan, and Sydney Water’s cooperation, the team went to work delivering this complex project without incident.
This Project now qualifies for consideration for the National CCF Awards.