Using a single 6m-deep central drill pit, Kerry Drainage & Civil delivered two trenchless stormwater pipeline installations in opposite directions, combining microtunnelling and HDPE pipe installation to minimise surface disruption along Pah Road.
Kerry Drainage & Civil was engaged by CDS as a specialist subcontractor for the Pah Road Stormwater Upgrade for Healthy Waters. KDCivil’s scope involved installing two sections of new stormwater pipeline using trenchless construction methods.
The project included 64m of DN700 GRP jacking pipe and 123m of 560mm OD HDPE pipe, both installed at a 0.6% grade. The works also required the construction of drill pits and manholes to depths of up to 6m.
A central drill pit was constructed to approximately 6m deep, providing the launch point for both trenchless drives. This approach allowed KDCivil to complete the two sections from the same excavation, reducing the number of major excavations required along the route.
The first drive installed the DN700 GRP pipe. A jacking bed was established at the receiving end, with the GRP pipe progressively jacked back towards the central drill pit.
Once the first drive was complete, the drilling equipment was repositioned for the second installation. KDCivil used a Cut & Pull methodology to install the 560mm OD HDPE pipe string, completing the second trenchless connection from the same central pit.
The combination of drilling, pipe jacking and Cut & Pull techniques provided a practical solution for installing the new stormwater infrastructure while working within the constraints of the existing road environment.
