Lifesavers have pleaded for people to wear flotation devices when trying to save others from waterways after two fathers died rescuing their children from rips.
Sergeant Peter Stone lost his life rescuing his son caught in a rip at a NSW south coast beach near Narooma on New Year's Day.
Another father, aged 42, died while rescuing his teenage daughter from a rip on Back Beach near Forster on January 3.
The two fathers are among six people to have died in NSW waters over the summer holiday period - all on unpatrolled beaches.
Surf Life Saving NSW chief executive Steven Pearce said he understood people would seek refuge from the crowds in patrolled locations but pleaded for them to think ahead.
"Know what a rip looks like and more importantly, plan what you are going to do if you or someone does get caught in a rip in an unpatrolled location," he said on Thursday.
"Anyone entering the ocean to perform a rescue - if they have to at all - should use a flotation device. This can be an item they have brought with them like a surfboard or body board."
In some cases, authorities could scramble help to unpatrolled locations when alerted via a triple zero call "so it is imperatively important to ring triple zero in the first instance".
He urged people not swim alone in inland waterways and ensure people were "very confident with your swimming capabilities".
Like in the ocean, only enter the water with a flotation device if trying a rescue.
"But importantly if you are swimming in an inland location and you do see someone in trouble, please ring triple zero," he said.
More than 1200 people were rescued from NSW beaches between Christmas Day and January 2 in what was one of the busiest periods in the past six years, Mr Peace said.
"Not one drowning has occurred between the red and yellow flags (in that period). All drownings have occurred in unpatrolled locations," Mr Peace said.
"We have an abundant amount of resources there to protect the community over the summer period with our drones, our helicopters, dozens of jetskis and obviously thousands of life savers."
Marine police inspector Dave Carlin said the death of Sgt Stone was a "tragic accident".
"He's a father. I'm a father. It was his fatherly instinct when he went in there. It's what he does for a job as well," he said.
He reminded the public to check water conditions before going swimming or boating.
"A key point in water safety is to make an assessment of the conditions before you're going in and putting in some precautions to minimise those risks," he said.
Life jackets are advised for boaters and rock fishers, while the legal blood alcohol limit for those driving boats is 0.05.
The warnings come as Queensland authorities issue a similar message after a woman almost drowned at Coolum Beach on Wednesday nihgt.
She was taken to Sunshine Coast University Hospital in a critical condition.
Prime Minister Anthony Albanese said life savers deserved thanks for working so hard to keep Australians safe over the summer.
"The best way to thank them is to listen to their directions, swim between the flags and stay safe," he wrote on Twitter.