Three young swimmers sucked into a rip and separated during a night swim at Bethells Beach were minutes from going under before off-duty lifeguards went to help.

The incident unfolded after 8.30pm yesterday, more than three hours after patrols had finished for the day.

The trio had spent the day at the beach celebrating an 18th birthday and decided to go for another dip when disaster struck.

Bethells Beach Surf Life Saving Patrol president Daniel Harvey said two off-duty lifeguards were alerted to the emergency by members of the public and initiated the rescue efforts.

“If there was a delay, the outcome would have been a lot different,” Harvey said.

“By this time the sun had already set and it’s quite dangerous to be driving when there’s low light.”

Four lifeguards attended in two inflatable rescue boats, identified the rip and followed it out.

The swimmers who were “spread over a wide area” were recovered individually and brought ashore within 20 minutes of the initial emergency call.

A second wave of responding lifeguards received them on the beach and provided medical treatment.

“We chucked them straight in the surf ute and put the heaters on because they were hypothermic,” Harvey said.

“Our first aid room is not the biggest so to have three patients in there, that involves temperature checks, blood glucose and listening to their chest.

“It took a while for them to become stable and to bring those emotions down because it’s a life-and-death situation, they’re obviously quite distressed.”

Two were transported to Waitākere Hospital by ambulance and the other was able to go home with whānau.

The team at Bethells Beach Surf Life Saving Patrol worked after hours to rescue three swimmers. Photo / Bethells Beach Surf Life Saving Patrol

Harvey said the team of 13 lifeguards involved in the rescue effort “performed very well under pressure”.

“We are just volunteers, so when the phone goes we’re either having our dinner, or just finished work, or with our families.

“But we train regularly and we’re used to these sorts of situations.”

Harvey said there has been a concerning rise in after-hours callouts at Bethells; five in the past three weeks, compared to 12 all last year.

“We strongly urge, with the really hot weather at the moment, that people do the right thing and really assess the situation, make good decisions so you can come home to your whānau.”

Harvey said he “completely” advises against swimming at night.

“Or if you do, pick a beach that is not the wild west coast.

“Never swim alone, always have family with you, and as much as possible, swim when there is a patrolled area on location and operating.”