Northland's deputy harbourmaster has urged people heading out to the waters to take care to keep themselves and their loved ones safe.
Chidambaram Surendran said there were a number of steps boaties could take, including ensuring boats were well maintained and serviced.
"Avoiding alcohol, wearing lifejackets, checking the weather forecast, letting someone know where you are going and ensuring you have proper means of communication on board in case something goes wrong all make for safe boating," he said.
Of particular concern to the Northland Regional Council was the incorrect use of dive flags.
He said in recent months a number of skippers had been forced to take evasive action to avoid divers because flags were nowhere to be seen or dive boats were not near their divers.
Under council bylaws, a dive flag must be displayed so it was clearly visible from another vessel 200 metres away.
Damage to navigation aid should be immediately reported otherwise other vessels may be in danger.