Structural relining of gravity sewer mains – Interflow’s process
Byron Shire Council has engaged the services of specialist contractor Interflow to undertake various rectification works on the existing gravity sewer network throughout Mullumbimby.
Since 1991 Interflow has installed over 2,500 kilometres of their structural liner (Expanda Pipe) in Australia. The minimum useful life guarantee of this product is 50 years. Interflow has a documented process that is strictly followed and certified by the site engineer to ensure the integrity of this new asset meets Council’s needs well into the future.
The process is well trialled and tested with over 2,500km of this product being previously installed by Interflow.
The relining process involves:
- Initial cleaning via pressure water blasting of the existing gravity sewer main to remove all obstructions and dirt from the inner wall of the pipe.
- CCTV inspection of the existing gravity sewer main to ensure the path is clear for installation of the new structural liner.
- Insertion of the structural liner winding machine in the maintenance hole and connection of the liner to the winding machine.
- Installation of the liner until it reaches the next maintenance structure.
- Final CCTV inspection to ensure there are no defects or bulges in the liner.
- Cut out and sealing of all property connections and sealing of both ends at the maintenance hole.
Structurally relining a gravity sewer main typically takes between 1-2 days. This includes preparation of the existing main, installation of structural liner, cut out of all existing private properties, and connections at each maintenance hole.