Lifeguards at Waitarere Beach have been kept busy rescuing people from surf due to flash rips appearing at low tide, prompting a warning from those tasked with beach safety.
A majority of incidents at the beach resulting in rescue in recent weeks have occurred at low tide, when strong undercurrents created by channels in the sand have caught swimmers by surprise.
There had been multiple incidents in the last week where swimmers had been assisted from the surf by lifeguards after becoming distressed.
Levin-Waitarere Beach Surf Lifesaving Club committee member and lifeguard supervisor Brian Forth said the channels that caused the flash rips were low spots created before low tide by surf.
"We work really hard to be preventative but on occasion there is a surprise, like a flash rip," he said.
Recognising a flash rip at low tide one afternoon last week, lifeguards moved the flags accordingly to a more safer spot, he said.
"There's been a bit of a wave and you usually get a stronger undertow and the channels seem to be on the outgoing low tide. It can move very quickly and drag people out," he said.
Although the message was reinforced every summer, Forth said he couldn't emphasise enough how important it was to swim between the flags.
The club patrols the long stretch of beach between the Hokio stream and Manawatū River. They simply couldn't watch every swimmer scattered along the 11km beach.
Forth said if a swimmer did get into trouble they had a greater chance of being rescued between the flags.
But flash rips weren't the only thing keeping lifeguards busy at the beach, with a variety of other rescues taking place away from the flagged area, in what was a busy time for the Waitarere crew.
One rescue was further out at sea and involved a jetski that had flipped. The driver had become distanced from the craft and was unable to climb back aboard.
Another rescue involved three people who were floating on a tyre inner tube and were swept out beyond the breakers, at the mercy of the sea with no means of propelling themselves back to shore.
It wasn't just incidents on the water, either. Lifeguards also attended a quad bike accident where the driver had rolled the bike after hitting soft sand.
The club has three paid lifeguards on patrol on weekdays between 11am and 6pm, aided by a grant from Horowhenua District Council, while it relied on volunteer guards to patrol the beach on weekends.
At their disposal were a range of rescue methods, either using the IRB, a kneeboard or swimming out with an buoyancy device.
Often time was of the essence and lifeguards used whichever method best suited the rescue, depending on the situation and the conditions.
Modesty was dangerous, too, as anyone wearing clothes in the surf was more likely to strike difficulty as clothes acted like a dead weight on a struggling swimmer.