The Coastguard is urging boaties to stick to common safety practices during the city's 173rd Anniversary Day Regatta today after a plywood runabout sank in the Motuihe Channel yesterday.

Two men who were heading out to fish were plucked from the water about 7am by a passing boatie. What could have been a very nasty situation was changed by the pair heeding safety messages, Coastguard spokeswoman Georgie Smith said.

"They've come off a wave and noticed a hole and that they've been taking on water very quickly. They spent 10 minutes in the water hanging on to chillybins.

"These people were wearing lifejackets and they've greatly increased their chances of survival and they've done the right thing by both having them on. As the boat sank, they were able to be seen by a member of the public, who has picked them up.


"It was absolutely heartening they'd taken heed of the safety messages," Ms Smith said.

Staff on a Coastguard vessel were on the scene within 20 minutes. They assessed the men - one aged in his 40s and the other in his 50s - and dropped them back at Half Moon Bay, from where they had launched.

Ms Smith said the service wanted everyone to have a happy public holiday out on the water. Traditionally one of busiest days of the year on the Waitemata, it will draw hundreds of boats either to compete in events or as spectator craft, making it imperative that people check the marine forecast this morning, be courteous and make sure they had two forms of waterproof communications such as a VHF marine radio and a cellphone in a plastic bag.

Today also marks a year since Jill Hetherington was seriously injured when the classic boat she was on, the 10.4m Gypsy, split in half after another yacht, the Antaeus - skippered by businessman Charles St Clair Brown - hit it.

Then aged 60, she suffered a fractured pelvis, nerve damage and deep bruising.

Her partner, John Pryor, who was also on board, told the Herald Ms Hetherington would be competing in the regatta in a tugboat race.

She was unavailable for comment but Mr Pryor, who has been critical that Mr St Clair Brown received a $200 harbourmaster fine and nothing else, said the amount of traffic in the harbour today should make people wary.

Where and when

Starts at 8.30am

Best viewing points

Bastion Point, North Head, East Coast Bays, Tamaki Drive, Orakei Wharf, Princes Wharf