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A young woman washed out to sea while whitebaiting on a South Island river says she forced herself to stay calm as she waited to be rescued.
Michelle Pitcher, 21, and her partner, Jake Greenlaw, 21, were caught in a current at the Rakaia River mouth, about 50km southwest of Christchurch, when the river floor disappeared beneath them.
"Little known to us there was a nice drop-off, which was hidden by the high tide," Mr Greenlaw said.
"We were standing a couple of metres from it and one of the waves ... just forced us back a couple of steps, and then the gravel sucked out underneath us."
It took all of his strength to struggle back to shore, but Ms Pitcher could not fight the pull of the water and was carried almost 100m out to sea.
"I didn't really start panicking until I was caught in the current and I realised I wasn't going to be able to get back ... to the shore," she said.
"It all happened so quickly. But once I was out of the current and just drifting in the ocean, I sort of calmed down and got rid of my [whitebaiting] bucket.
"I dropped the net and just lay there and tried to relax. I just had to wait and keep calm."
Mr Greenlaw said seeing Ms Pitcher getting pulled out to sea was a terrible sight.
"It was quite hard to keep a cool head and not dive in after her."
Ms Pitcher had no idea how long she would be stranded but after about 10 minutes a nearby boat was able to get to her.
She said the boat's arrival was "sweet relief - just a great feeling. I sat there stunned while they drove me back to shore".
The pair were lucky the sea on Sunday was calm so the boat was able to get to Ms Pitcher. They were both wearing lifejackets.
"Without a lifejacket, I wouldn't have liked our chances," Mr Greenlaw said. "It's a real strong current. It took a full-out effort to get anywhere. To swim sideways out of the current was just all you could muster to get out of it."
Mary Hood was riding her four-wheel-drive motorbike nearby when she saw the pair fall into the river.
She had seen the same thing happen before and said it was a frightening sight.
She rushed to find help from those in the boat and then called police, who were on the way but were not needed.