Smoke Testing of Sewer Infrastructure  

Interflow Pty Ltd will be conducting Smoke Testing of sewer infrastructure in areas of the Lithgow Government Area for a 4-week period commencing on 8th July 2024. 

Smoke testing is carried out to locate defects in the public sewage network and in house service lines.  These defects can result in stormwater runoff entering the sewer system, resulting in additional load to the system. 

 Lithgow City Council has engaged the services of Interflow Pty to conduct smoke testing of over 250 properties in the Lithgow areas along Main Street and Landa Street, in addition to 15 properties to be retested around extension estate.  

 This will require Interflow staff to enter outdoor areas of your property.  

Interflow will provide two days’ notice before smoke testing in your area. You do not need to be present, however please contact the Interflow Construction Manager should you wish to arrange a time for testing on your property.   

 Following completion of the testing, property owners will receive written correspondence from Council containing the results and the steps that will need to be taken in order to rectify any problems within that property including the responsibility of Council and the residents in this work. 

 Ensuring the sewerage capacity of the region for sustainable growth and development has been identified as measure to enhance the natural environment in the 2013 – 2026 Community Strategic Plan. 


What is smoke testing?

This is where our contractor pumps a vapour-like smoke into local sewer pipes as a way of discovering sewerage system faults and non-compliant household stormwater connections. 

Sewerage system faults and non-compliant stormwater connections can lead to sewer spills, public health risks, serious environmental impacts, and losses for the local marine and lake industries.

What is a non-compliant stormwater connection?

This is where household stormwater plumbing is found to be connected to a Council-owned sewer instead of a stormwater drain. This is a breach of Clause 638 of the Local Government Act.  

What happens if my property is found to have a non-compliant connection?

We will send a notification providing details of what the property owner needs to do next. The property owner is responsible for all rectification costs.  

When will you be testing in my area?

Smoke Testing in the Lithgow City LGA will be performed between8 July and 8 August 2024.  

What is the smoke? Is it harmful?

The smoke is non-toxic, non-staining and odorless. However, we recommend people with respiratory problems to avoid direct exposure to the smoke. To minimise the risk of smoke entering your home, please ensure showers, toilets, sinks and floor drainage have been recently used. 


Main St Sewer Map
Landa St Sewer Map

Project Timeline

  • Project start – 8 July 2024 

  • Expected completion – 8 August 2024