KNOWING a mother and her two children were just metres away as they sunk to the bottom of the Tweed River has devastated a former police officer who tried to rescue them.

A mother and her daughter and son were trapped after the car they were travelling in flipped into waters made murky by recent flooding at 1.40pm yesterday.

A nine-year-old girl miraculously escaped from upturned vehicle after it ran off Dulguigan Road at Tumbulgum.

As the car sank with her mother and siblings trapped inside the girl ran to a nearby home where her family are believed to have been staying to raise the alarm.

Three dead in Tweed River tragedy.
Three dead in Tweed River tragedy. Glenn Hampson

But by the time they had returned to the river's edge the car had disappeared from sight and all that remained was a trail of bubbles.

"They had no chance, no chance," said former highway patrol officer Matt Grinham, who tried to rescue the family along with two other men.

Mr Grinham, who retired last year after 23 in the job, spoke of the anguish he felt at not being able to reach the family.

"It's never easy. It was just the helplessness of not being able to find the car," he said.

"The bubbles were there. We could find the bubbles. We just couldn't get to the car.

"It was just too deep, too cold, as soon as you opened your eyes underwater it was horrendous. It was freezing cold."


A would-be rescuer has described how he desperately tried to save three people trapped in a sinking car at Tumbulgum yesterday.
A would-be rescuer has described how he desperately tried to save three people trapped in a sinking car at Tumbulgum yesterday. Glenn Hampson

Mr Grinham said he was travelling to help clean up flood damage at a relative's property across the river from the accident with his two children Thomas, 15, and Sophie, 12.

He said he didn't know what had happened until a woman nearby told him. That's when he saw the skid marks leading to the water.

"She just looked so frantic," Mr Grinham said. "Then I saw the skid marks on the road."

He said recent rains had made the search almost impossible. "It was hard to keep swimming against the current, you had to keep coming up and all you could see was the bubbles," he said.

"At first we were going feet first just pushing down to try and see if we could feel it with our feet. I tried a couple of times.

"(But the bubbles) They trailed away. They just got less and less."


Three feared dead after car plunges into Tweed river at Tumbulgum Northern NSW.
Three feared dead after car plunges into Tweed river at Tumbulgum Northern NSW. Glenn Hampson

The child who managed to escape from the car was taken to Tweed Heads District Hospital with cuts and lacerations to her lower legs as well as neck pain.

The occupants of the house where she raised the alarm, Ben Darcy and his partner Sabrina Colomb, also spoke of their deep shock at what had happened.

Mr Darcy and his brother-in-law also leapt into the murky, flood-swollen river to try to rescue the family.

"It was just too deep; we couldn't get down far enough," Mr Darcy said. "We swam around and dived down but we couldn't see a thing."

Mr Darcy said he and his partner were cleaning up mud from ex-Cyclone Debbie when the girl turned up dazed and bleeding early yesterday afternoon.

"She was clearly in shock," Mr Darcy said. "She said 'our car just went into the river'. She said her mum was still in it.

"We just bolted up there as fast as we could."

The scene of the tragedy at Tumbulgum.
The scene of the tragedy at Tumbulgum.

Police said divers would begin their search to retrieve the bodies in the car today after poor conditions and dying light hampered yesterday's search.

Despite this Mr Grinham took his tinnie out into the water with a depth sounder to make sure the car hadn't moved late yesterday.

"We fish the area regularly, we know there isn't really anything else through there," he said.

NSW Police Assistant Commissioner Jeff Loy said the road the car was travelling on was closed.

"That road was actually closed because of the debris and the mud on the road," he said.

"We really understand that people want to get to where they need to be and live their lives normally, but this is an extreme event.

"This is about heeding the warnings of the road closures.

"This has been a major event and the emergency services don't take those closures lightly."