The project required the lining of approximately 1,200 m of reinforced concrete ovoid sewers ranging between 380 x 226 mm and 685 x 460 mm in size, as well as 200 m of 610 mm diameter reinforced concrete circular sewers.
Rehabilitation work on access chambers along the route was also required.
With sections of the sewer constructed as far back as 1908, refurbishment was needed to ensure it continued to service customers.
For the project, ovoid sewers were lined with cured-in-place pipe (CIPP) liners ranging from 7 mm to 16 mm in thickness.Article continues below…
Liner wet-out and installation was mostly undertaken at night to avoid the summer heat, as well as to minimise disruption to traffic, and curing of the liners took place during the day.
Installation was possible through some of the intermediate access chambers, with the longest continuous liner installed reaching 213 m.
The installation of the liner blocked the pipe for some time, and therefore flow management was necessary so as to allow for services to be maintained for customers.
Interflow developed a flow management plan that included construction of a temporary wet well, installation of a bypass system, tankering, and closing down of sewer pumping stations for limited periods, in co-operation with the Water Corporation.
The main part of the bypass system used 1.2 km of DN315 polyethylene pipe work along a route chosen to minimise inconvenience to the community.
Where the bypass pipe work had to pass under the Canning Highway it was sleeved into an existing larger diameter stormwater pipe.
Thrust boring was used to install the pipe work under other roads and under driveways to minimise inconvenience to householders and road users.