Emergency Information

Wastewater and COVID-19 information

20 November 2020

We understand that there are some questions regarding the discovery of traces of COVID-19 in Benalla's wastewater.
Here's some timely information from the Department of Health and Human Services you may find of interest.
What is wastewater and why is it being tested?
Wastewater is used water from toilets, showers, baths, basins, sinks and laundries that passes through the sewerage system.
Wastewater across Victoria is being tested because the presence of viral fragments shows that SARS-CoV-2 – the virus that causes coronavirus (COVID-19) – has been recently shed in the geographical area of the sewerage system catchment.
Fragments of the virus detected in untreated wastewater in locations where there have been no recent known cases of coronavirus (COVID-19) may indicate visitors or people within that community have coronavirus (COVID-19) and may still be infectious. This early warning can lead to increased local vigilance and clinical testing, and allow health authorities to target public health advice to prevent transmission.
How do traces of coronavirus (COVID-19) get into wastewater?
People who have or recently had coronavirus (COVID-19) may shed the virus on used tissues, off their hands and skin when washing and in their stool. It can take several weeks for someone to stop shedding the virus. Over time the virus breaks down and small non-infectious pieces of the virus (called ‘viral fragments’) can enter wastewater and travel through the sewer network.
How are wastewater samples taken and tested?
Samples of untreated wastewater are collected from sites across the metropolitan and regional sewerage network including from the inlet to wastewater treatment plants. The samples are taken to a laboratory and analysed for fragments of SARS-CoV-2 – the specific coronavirus associated with COVID-19.
Poliovirus, norovirus and adenovirus are also routinely monitored in wastewater around the world.
How are sample sites chosen?
The wastewater surveillance program is adaptive. The Department of Health and Human Services chooses sampling sites based on a number of factors including population size and feasibility to access samples, with the main aim to provide the most useful data in the context of the Victorian coronavirus (COVID-19) response.
Does a positive wastewater test result always mean that there is an active case of coronavirus (COVID-19) in a local area?
No. A positive wastewater test result may be due to a person or people with coronavirus (COVID-19) being in the early active infectious phase but it may also be due to someone or people who are no longer infectious continuing to shed the virus. The person or people shedding the virus may be local or visitors to the community.
Can I get coronavirus (COVID-19) from wastewater?
No. There’s no evidence that the virus causing coronavirus (COVID-19) can be transmitted through wastewater, either before or after treatment. The viral fragments themselves are not infectious.
Wastewater is treated to kill a wide variety of microorganisms, including viruses, before it is returned to the environment. There is no evidence that coronavirus (COVID-19) can be spread via recycled water nor via treated wastewater released to waterways.
Is my drinking water safe?
There is no impact on your local water supply from wastewater testing. Drinking water supplied by water utilities is safe to drink and for normal household uses.
Who is involved in the wastewater surveillance project?
The Department of Health and Human Services is overseeing the Victorian wastewater surveillance program with support from Victorian water utilities in the collection of wastewater samples. Victoria is a member of the collaboration for sewage surveillance for SARS-CoV-2 (ColoSSoS). Coordinated by Water Research Australia, the ColoSSoS project brings together health departments, water utilities, laboratories and researchers from Australia and New Zealand to share advances in this rapidly evolving field.
Laboratories and researchers involved in developing testing methods include Australian Laboratory Services, the University of Melbourne, Melbourne Water, Monash University, Victorian Infectious Disease Reference Laboratory, Walter and Eliza Hall Institute, SA Water and Sydney Water.
For more information
Visit DHHS.vic – Wastewater testing <https://www.dhhs.vic.gov.au/wastewater-testing-covid-19>.

< Return