A man has drowned on a popular beach in Adelaide after trying to rescue his young daughter who had been swept off the coast.

Witnesses say the 49-year-old Seaton man swam out to sea at Grange Beach in the west of Adelaide to save his daughter after she was blown offshore on an inflatable pipe on Thursday morning.

Michael Napper, 70, was playing with his grandchildren on bodyboards when he saw the man on his way into the water to save his daughter.

“I ran out to get to him,” Mr. Napper said.

“Before I got there, the little daughter jumped off the pipe and into his arms in deep water, and he tried to save her.”

He then said the pipe was taken away from the pair by a strong wind.

“I managed to get her on the board,” he said.

“When I reached him, he was underwater, and the next thing he floated, and that was when I grabbed him by the pants and turned him over and got him over the water.

The man was pulled unconscious out of the water along with his distressed daughter with the help of other beachgoers.

“I think I could have reached them before, and I’m sorry I did not.”

Despite CPR attempts by members of the public and paramedics, the father could not be resuscitated.

Surf Life Saving SA’s Daniel Willetts said there had been four coastal drownings in six weeks in southern Australia.

He warned against using inflatable toys offshore.

“Already today we have seen two incidents of that nature today and it has resulted in assistance from emergency services. So we urge people not to take your pool toys to the beach,” said Mr. Willetts.

“If you find yourself in a sudden offshore wind, you will be swept out to sea and you will find yourself in trouble.”

He urged people to be extra careful in the coming weeks.

“With the hot weather on the way and school holidays … the beaches are getting busier … please swim between the flags, swim in a patrolled area”.