French Drain Case Study: Managing Runoff in Shellharbour

Resolving Water Ingress Challenges in Shellharbour

A homeowner in Shellharbour encountered a serious and worsening problem with water ingress. Water from two adjacent properties situated at a higher elevation began to flow into their garden and infiltrate beneath the house's foundation. This unwelcome water intrusion caused extensive damage to the flooring, promoted rising damp, and encouraged mould growth within the home, jeopardising recent renovations.

How Can You Identify Signs of Water Intrusion?

The water ingress issue originated from both surface runoff and subsurface water cascading downhill from the back and side yards of neighbouring properties. Without an effective drainage solution to intercept this water, it inevitably made its way beneath the house.

Creating an Effective Drainage Solution

CS Plumbing designed and implemented a gravity-fed French drain system aimed at capturing and redirecting water before it could reach the home’s foundation.

The project comprised several vital components:

A French drain system specifically designed to collect both surface and subsurface water from neighbouring properties, efficiently channelling it through gravity to a concrete pit.
A 100mm PVC pipe extending from the pit to the curb, equipped with strategically drilled holes to ensure optimal water discharge.
Three new, larger-diameter Colorbond metal downpipes, replacing the original smaller versions, connected to new 100mm PVC piping leading to the curb.
A retaining wall system constructed along the boundary, utilising concrete sleepers and galvanised steel posts, with auger holes drilled using an excavator to establish a solid barrier that holds back the adjacent yard.
Efficient on-site soil removal managed with a dumper to streamline the workflow.

What Measures Can You Implement for Effective Water Management?

The newly installed drainage system now effectively captures both surface and subsurface water at the property boundary, ensuring it is diverted away from the home. The homeowner has achieved a robust, low-maintenance solution that safeguards the foundation, flooring, and their investment in renovations.