This is the third detection at the Eden sewage treatment plant.

Bega Valley Shire Mayor, Russell Fitzpatrick said undetected COVID-19 cases within the Bega Valley Shire remains a strong possibility.

"As more fragments are found across the shire, the possibility of there being unknown local cases increases," Cr Fitzpatrick said.

"If you live in Eden or the surrounding areas, or in fact anywhere in the shire, and you have the slightest hint of cold-like symptoms, you need to get tested.

"This means if you are experiencing symptoms such as headache, nausea, sore throat, runny nose, cough, loss of smell or taste, or fever, you must get tested and isolate until a negative result is received.

Cr. Fitzpatrick said he encourages people across the shire to get vaccinated.

"A walk-in Indigenous vaccination day organised by local health professionals was held in Eden on Saturday, September 25.

"The clinic is a great initiative and a wonderful service to the community," Cr Fitzpatrick said.

The Eden sewage treatment plant serves approximately 3000 people.

Council is sending samples from the sewage treatment plants in Eden, Bermagui, Merimbula and Bega, twice weekly to NSW Health for testing.

Testing facilities and hours can be found at www.snswlhd.health.nsw.gov.au/our-services/infectious-disease/covid-19-testing

COVID-19 cases and venues of concern are published on the Southern NSW Local Health District website at www.snswlhd.health.nsw.gov.au/our-services/infectious-disease/covid-19-venues-of-concern

For the latest COVID-19 updates and advice, go to www.nsw.gov.au/covid-19