French Drain Case Study: Managing Runoff in Shellharbour

Addressing Water Ingress Challenges in Shellharbour

In Shellharbour, a homeowner encountered a pressing 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 intrusion of water caused substantial damage to the flooring, promoted rising damp, and contributed to mould growth within the property, jeopardising recent renovations.

How Can You Identify Signs of Water Intrusion?

The issue originated from both surface runoff and subsurface water flowing downhill from the back and side yards of neighbouring properties. Without an effective drainage solution to intercept this water, it inevitably travelled beneath the house, leading to significant concerns.

Creating an Effective Drainage System

CS Plumbing designed and implemented a gravity-fed French drain system aimed at capturing and redirecting water before it reached the foundation of the home.

This project comprised several critical components:

• A French drain system specifically tailored to collect both surface and subsurface water from neighbouring properties, effectively channeling it through gravity to a concrete pit.
• A 100mm PVC pipe running from the pit to the curb, featuring strategically drilled holes in the curb to ensure optimal water discharge.
• Three new, larger-diameter Colorbond metal downpipes that replaced the original smaller versions, connected to new 100mm PVC piping leading to the curb.
• A retaining wall system constructed along the boundary, employing concrete sleepers and galvanised steel posts, with auger holes drilled using an excavator to form a solid barrier that holds back the adjacent yard.
• Efficient onsite soil removal conducted with a dumper to ensure streamlined management of the worksite.

What Actions Can You Implement for Efficient 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 secured a reliable, low-maintenance solution that safeguards the foundation, flooring, and their investment in renovations.

Shellharbour French Drain Case Study: Practical Solutions for Managing Neighbour Runoff and Subsurface Water