Notification of wastewater overflow and bypasses

Sydney Water provides notification of overflows or bypasses. These tables list all events that have occurred in the last seven days.

If you see an overflow, please phone Sydney Water on 13 20 90.

Greater Sydney Region including Blue Mountains

Event type	Link to description
Waterways	Dry weather overflow into Waterway at Northmead  04/02/12
Wastewater treatment plant bypass	No Dry Weather WWTP bypass Notification

Illawarra

Event type	Link to description
Waterways	No Dry Weather Waterway Notification
Wastewater treatment plant bypass	No Dry Weather WWTP bypass Notification

Why it happens

Sydney Water's wastewater system transports and treats wastewater through a network of pipes, wastewater pumping stations and wastewater treatment plants (WWTPs).

In dry weather, overflows of wastewater can occur for many reasons. For instance, when there is a blockage in a wastewater pipe caused by tree roots or other material (PDF - 1.26MB) , or if a pump fails at a pumping station. At treatment plants, bypasses may result from a power failure.

In wet weather, stormwater flows into the wastewater system and may exceed the system's capacity and result in overflows from our pipe network and/or the diversion (bypassing) of one or more process units at the treatment plant. These events are recognised within the Environment Protection Licences set by Department of Environment, Climate Change and Water (NSW).

Sydney Water is committed to reducing overflows from our wastewater systems through our SewerFix, maintenance and improvement activities.

Property owners are responsible for maintaining the wastewater pipes and downpipes on their property to ensure plant roots and stormwater does not enter the wastewater system.

Definitions

Bypass	A wastewater treatment plant bypass occurs when flows exceed the hydraulic design capacity of one or more process units, and are diverted by means of a civil structure. Bypassed flows may rejoin fully treated flows and receive further treatment in down stream processes.	Bypass click image to enlarge
Overflow	A wastewater treatment plant overflow occurs when the flows received at the treatment plant exceed the hydraulic design capacity of the disinfection process unit. Despite exceeding the hydraulic design capacity, flows are still partially disinfected.	Overflow click image to enlarge
Tree roots	Roots can damage wastewater pipes, obstruct the flow and eventually cause blockage. Root damage can also let stormwater into pipes. During heavy rain this extra water can overload the wastewater system causing it to overflow into waterways and the environment. If the problem occurs in your private wastewater pipes, it is your responsibility to have it fixed.	Tree Roots click image to enlarge