Infiltration and Inflow to the Wastewater System
Infiltration is rainwater and ground water that seeps into the sewerage system through defective pipes and joints.
Inflow is stormwater and surface water that enters the sewerage system directly - usually from local flooding into low-lying gully traps, and roof downpipes directly connected to the sewer.
In periods of heavy rain, increased inflow to the sewerage reticulation network can cause overflows, which can lead to contamination of private properties, watercourses and lakes. The overloaded system may also mean reduced levels of treatment at the wastewater treatment plant.
For more information on our Inflow and Infilteration program contact the Utilities Department.