It's part of the reason why the regional lockdown will continue until midnight September 10, NSW Premier Gladys Berejiklian confirmed as NSW cases hit four figures in Thursday's update.

NSW Health's sewage surveillance program detected fragments of the virus at the Tamworth sewage plant that serves about 45,000 people.

Read also:

Everyone in this area is urged to monitor for the onset of symptoms, and if they appear, to immediately be tested and isolate until a negative result is received.

Ms Berejiklian said the government would offer its schools plan on Friday, but from September 13 that local government areas of concern in Sydney would be offered anhour of recreation on top of their hour of exercise - if they were vaccinated.

"A family will be able to go out and sit in the park, as long as the adults are vaccinated," Ms Berejiklian said.

Outside those areas, five people can gather outdoors as long as all adults are vaccinated.

"That five can include children, but as long as it's adults all of them will need to be vaccinated," Ms Berejiklian said.

"We know that people coming together is what people miss the most."

NSw recorded 1029 cases in NSW, with three deaths, including a man in his 30s, in the 24 hours to 8pm on Wednesday.

"Unfortunately all three were unvaccinated," Ms Berejiklian said.

The Sydney local government areas comprise 80 per cent of cases, Ms Berejiklian said, and urged people in those areas to adhere to the health advice.

"As far as western NSW is concerned we have seen obviously the concern level there continue ... however there has been a stabilisation of cases across the regions with the exception of western NSW."

Our journalists work hard to provide local, up-to-date news to the community. This is how you can access our trusted content: