French Drain Case Study: Managing Runoff in Shellharbour

Addressing Water Ingress Challenges in Shellharbour

In Shellharbour, a homeowner encountered a serious and worsening issue 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 water intrusion caused considerable damage to the flooring, contributed to rising damp, and promoted mould growth within the property, jeopardising recent renovations.

How Can You Identify Signs of Water Intrusion?

The issue arose from both surface runoff and subsurface water cascading downhill from the back and side yards of neighbouring properties. Without an effective drainage solution to capture this water, it inevitably flowed beneath the house.

Creating an Effective Drainage System

CS Plumbing designed and installed a gravity-fed French drain system that effectively captures and redirects water before it reaches the foundation of the home.

This project incorporated several crucial elements:

A French drain system meticulously designed to collect both surface and subsurface water from surrounding properties, efficiently guiding it through gravity to a concrete pit.
A 100mm PVC pipe extending from the pit to the curb, featuring strategically drilled holes to ensure efficient water discharge.
Three newly installed, larger-diameter Colorbond metal downpipes, replacing the original smaller pipes, connected to new 100mm PVC piping leading to the curb.
A retaining wall system constructed along the boundary, using concrete sleepers and galvanised steel posts, with auger holes drilled via an excavator to create a solid barrier that holds back the adjacent yard.
Efficient on-site soil removal conducted with a dumper to ensure smooth management of the work area.

What Measures Can You Implement for Effective Water Management?

The newly installed 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 durable and low-maintenance solution that safeguards the foundation, flooring, and their investment in renovations.