Surf Lifesaving New Zealand (SLSNZ) is warning beachgoers to swim between the flags after lifeguards rescued four people at Christchurch beaches over the weekend.
And at Piha, an entire family was rescued by surfers after they were spotted in trouble at the West Auckland beach outside lifeguard patrol hours on Sunday.
SLSNZ general manager of lifesaving Andy Kent said two swimmers became caught in strong winds outside the flags at Waimairi Beach in Christchurch on Saturday and had to be rescued.
On Sunday another couple had to be rescued at New Brighton's North Beach when they got into trouble swimming outside the flags.
He said in the Piha incident, off-duty lifeguards met the group on the beach and provided first aid care until the ambulance arrived.
Meanwhile, volunteer surf lifeguards put in more than 200 hours at Raglan as the Soundsplash Festival attracted 4000 visitors to the Waikato beach on Saturday.
"Despite the numbers, surf lifeguards reported that most people were sensible. Surf lifeguards performed three assists and responded to four first aid incidents."
Kent said while he was pleased most people around the country swam between the flags and while lifeguards were on duty, those who didn't were taking their lives into their hands.
"The flagged area is the safest place to swim and where lifeguards put most of their focus.
"If you swim outside of the flags or outside of duty hours you're leaving an awful lot up to chance."
He said there had been 28 water rescues around the country so far this summer.
With January traditionally being New Zealand's most dangerous month in the water, Kent urged beachgoers to think about the impact of their drowning on those around them.
"Losing a life due to drowning is devastating for friends and whānau, the person's community and the lifeguards involved in the incident.
"Please weigh up the benefit of swimming outside of the flags or outside lifeguard hours with the risk you're taking and the impact it would have on your friends and whānau if your luck were to run out."
Beachgoers can check which beaches in their area have lifeguards and the hours surf lifeguards are on duty online or by using the Swimsafe app.
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