We often take everyday services for granted, like turning on the tap or flushing the toilet, without ever thinking about what happens after. But underground drains don’t always run smoothly.
Over time, they can develop blockages or damage that need serious attention.
Blockages can be caused by tree roots pushing into sewer pipes, cracks or breaks in older drains, or even ground movement shifting the system. While some blockages can be cleared with temporary fixes, others require a more permanent solution to prevent the problem from returning.
One of the most common and important repairs we carry out is the excavation and replacement of the boundary trap and shaft.
HOW THE PROCESS WORKS
Accessing the Site
We begin by reaching the affected location, usually with an excavator. We dig down to the approximate depth of the drain.
Safe Excavation Methods
If it’s unsafe to use heavy machinery due to underground services, we use a Non-Destructive Digging Truck. This method uses high-pressure water and a vacuum to safely remove soil without damaging surrounding services.
Excavating to the Correct Depth
Sewer depths vary between properties. Sometimes the repair may be only a couple of meters down, while in other cases, we may need to dig several meters deep. The depth determines how we approach the job. To protect our team and comply with OHS standards, we install trench support and shoring systems when working at depth. This helps prevent trench collapse and ensures a safe working environment for those in the excavation.
Replacing the Damaged Section
Once exposed, we remove the affected section of drain and replace it with sewer-grade PVC, which is strong, durable, and designed to withstand future issues.
Stabilising the Repair
The new drain is carefully bedded with crushed rock and concrete. This helps lock it in place and reduces the risk of movement or future breaks once the trench is refilled.
Backfilling and Compacting
As we backfill, we compact the soil to minimise ground movement. It’s common for the area to settle slightly over the next 6 to 8 weeks, so we leave the surface slightly mounded to allow it to level out naturally.
Non-Destructive Digging Truck
Trench support systems to prevent collapse and protect workers during deep excavations
Completed Boundary Trap replacement