French Drain Case Study: Managing Runoff in Shellharbour

Resolving Water Ingress Challenges in Shellharbour

In Shellharbour, one homeowner encountered a serious and worsening problem with water ingress. Water from two adjacent properties, situated on higher ground, began to flow into their garden and infiltrate beneath the foundation of their house. This water intrusion caused considerable damage to the flooring, encouraged 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 flowing downhill from the rear and side yards of neighbouring properties. In the absence of an effective drainage solution to intercept this water, it inevitably made its way beneath the house.

Creating an Effective Drainage System

CS Plumbing designed and installed a gravity-fed French drain system intended to collect and redirect water before it could reach the home's foundation.

The project included several critical elements:

A French drain system specifically designed to gather both surface and subsurface water from adjacent properties, efficiently channeling it via gravity to a concrete pit.
A 100mm PVC pipe extending from the pit to the curb, with strategically drilled holes in the curb 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, using concrete sleepers and galvanised steel posts, with auger holes excavated to create a solid barrier that holds back the adjacent yard.
Efficient soil removal conducted on-site with a dumper, ensuring streamlined management of the worksite.

What Measures Can You Implement for Effective Water Management?

The newly established system now efficiently captures both surface and subsurface water at the property's boundary, directing it away from the home. The homeowner has secured a durable, low-maintenance solution that safeguards the foundation, flooring, and their investment in renovations.