An 8-year-old boy was saved from beneath a capsized boat in one of two river mouth incidents at the weekend.
The incidents come as the Coastguard warns about sandbars amid increasing boat usage with Covid-19 restrictions eased.
Tragedy was narrowly averted in two separate incidents on Sunday - one at the mouth of the Manawatū River and one just kilometres away near the Ōtaki River mouth - after rough sea caused the boats to capsize.
On each occasion there was someone trapped underneath each boat, lucky to survive.
In the first incident, two men were credited with helping save the lives of an Ōtaki family whose boat capsized in rough sea earlier in the day.
The two men, who want to remain nameless, were near Ōtaki River mouth when they spied what looked like a boat in trouble.
"It was horrendous. They were merciless to the sea," one of the men said.
Next minute, they saw the boat flip over in big surf. They raised the alarm, stripped down to their underwear, and took to the freezing water.
The water was over their head as they swam to the boat. There, they found an 8-year-old boy trapped under the boat, much to his distress, and that of his parents.
The boy was breathing through an air-pocket near the front of the overturned boat as waves continued to batter the vessel.
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With the help of a policeman, the boat was overturned and the family were able to be dragged back to shore where they received treatment for minor injuries.
Later that afternoon, another boat, this time with a Levin father and his teenage son on board, got into trouble and flipped on the a notorious sandbar at the Manawatū River mouth.
The man was trapped underneath his vessel for a time.
Manawatū Volunteer Coastguard was alerted and deployed jet skis to the scene. The Coastguard rescue boat was used to take the pair back to the boat club where emergency services were waiting.
The man was taken by helicopter to Palmerston North Hospital where he still remains today, receiving treatment for concussion and injuries that included a suspected broken sternum.
The boy was taken to hospital by ambulance for observation and treatment to cuts and bruises.
Manawatū Volunteer Coastguard president Eddie Bambury said the boat got into trouble due to rough sea that drove it into the sandbar, forcing it to roll.
"There are always people that want to stay out a bit later when the fishing is good. But the weather conditions can change too. You have to read the conditions and read the water," he said.
It was due to swift action of people onshore in alerting emergency services that the occupants of the boat were rescued and able to get urgent medical attention.
"They were very lucky," he said. "It cut up rough."
Bambury said the incident highlighted the dangers of the sandbar for any boat coming in from the sea, up river to the boat ramp outside the Manawatū Boating Club, where boats were launched.
There were markers to guide boats in and out through a channel, but the channel could change course over time. The sandbar, which made the river mouth very shallow at low tide, moved over time.
Boats were advised to cross the sandbar two hours before high tide and come back to the river two hours after to minimise risk.
A team of volunteers manned a radio at the club. Boats were required to radio through to the Foxton Sports Radio channel (VHF60) before they had crossed the bar, and again when they were safely over it, and repeat the practice when returning.
The radio operators are all volunteers who work on a roster and "do a bloody good job", he said.
Bambury said there was a large increase in the amount of boats taking to the water after the Covid-19 restrictions were lifted. There were as many as 30 boats out on the water at one time at the weekend.
"After lockdown was over every man and his dog was out there," he said.
Meanwhile, Manawatū Volunteer Coastguard was called to another event at the weekend from a broken down boat. The crew were trying to return to shore, but couldn't get their motor going after flooding the engine.