French Drain Case Study: Runoff Management in Shellharbour

Addressing Water Ingress Issues in Shellharbour

A homeowner in Shellharbour faced a significant and escalating issue with water ingress. Water from two adjacent properties at higher elevations began to flow into their yard and seep beneath the foundation. This infiltration resulted in damage to the flooring, encouraged rising damp, and triggered mould growth within the home, jeopardising the integrity of recent renovations.

Identifying the Root Causes of Water Intrusion

The water ingress stemmed from surface runoff and subsurface water flowing downhill from the back and side yards of neighbouring properties. Without sufficient drainage to intercept this flow, the water inevitably made its way beneath the house.

Creating a Reliable Drainage Solution

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

The project included several essential components:

• A French drain system designed to gather both surface and subsurface water from neighbouring properties, directing it through gravity to a concrete pit.
• A 100mm PVC pipe extending from the pit to the curb, featuring strategically drilled holes to ensure effective water discharge.
• Three new, larger-diameter Colorbond metal downpipes that replaced the original smaller ones, connected to the new 100mm PVC piping leading to the curb.
• A robust retaining wall system constructed along the boundary using concrete sleepers and galvanised steel posts, with auger holes excavated to form a secure barrier to hold back the adjacent yard.
• Efficient soil removal conducted on-site using a dumper for streamlined site management.

Ensuring Efficient Water Management

The newly implemented system successfully captures surface and subsurface water at the property boundary, diverting it effectively away from the home. The homeowner now enjoys a durable, low-maintenance solution that safeguards their foundation, flooring, and investment in renovations.