Lucky escape as boat flips at 'treacherous' Tairua bar

A boatload of people had a lucky escape after rough seas flipped their vessel on a "treacherous" bar at Tairua on the Coromandel Peninsula.

Video provided to the Herald shows the Coastguard towing the submerged, upside-down boat before a crowd of people helped right it.

Andrew Gibson, president of the Tairua-Pauanui Coastguard unit, said it was low tide at the time the boat capsized. There was a 1.5-2m swell when the unit was called out around 12.45pm.

The Pauanui surf lifesaving club had picked up the boat's passengers, none of whom were injured, but the boat had been upturned and was on the inside of the bar.

Coastguard worked together with the surf club to tow the upturned boat to Pauanui to Royal Billy Point, where with the help of the public they righted the boat, pumped it out and got it over the sand bar back to its owner.

"It just had a little bit of damage but the engine would be full of water - that's never good for a boat."

He did not know the circumstances of the boat flipping, and said it was "thankfully" not a frequent occurrence.

"But it is a treacherous bar, especially at low tide," he said. "Some people do [cross at low tide] but it depends on the size of the swell. It's just nice to see the people weren't injured."

Meanwhile, a man has died off the Canterbury coast while another person is unaccounted for in Hamilton after a host of issues on the water around New Zealand today.

Police said a man died in the sea south off Motunau Island off the Canterbury coast today. The island, uninhabited but a refuge for sea birds, is close to the coastline of Pegasus Bay, north of Christchurch. The man was reportedly diving.

In a separate incident, emergency services are responding to a water-related incident at Hamilton Gardens. Police say their first report was received shortly after 6pm. One person is unaccounted for in the water.

Two people have also been taken to hospital this afternoon after separate water incidents at holiday hotspots on the Coromandel Peninsula.

At 1.53pm St John was called to an incident at Waihī Beach, with one ambulance, one first response unit and one rapid response unit sent to the scene.

A St John spokeswoman said one patient was treated in a serious condition and was transported to Tauranga Hospital.

Emergency services were called at 2.01pm to an incident on Hahei Beach Rd, the spokeswoman said. Around 2.30pm a Westpac rescue helicopter was at the scene but an ambulance crew and the fire service were still en route.

St John treated one patient in a minor condition and transported them to hospital.

Hahei Beach sits between the popular Cathedral Cove and Hot Water Beach. The town of Hahei normally has just a few hundred residents but this can swell to several thousand over summer.