"I'm not anti-port, I'm pro-port, I'm pro-reclamation, I'm pro-progress, but Auckland harbour, where they are reclaiming, is less than half the width it used to be - it's turned from a harbour into a river," he said on Newstalk ZB this morning.
"It's dangerous, it's unsightly. You can't take a little boat around that corner any more, it's a tidal rip there's so much water going through. Enough is enough.
"They're stealing a harbour to make a carpark, we've had enough."
His outrage was backed by Moa Brewing boss Geoff Ross, who said he believed the port authority could continue to work and expand "in a better way".
"We proudly show visitors our city and we say, 'look at this beautiful harbour, it's a unique asset for our city, just lift your vision a little bit so you can see over that huge car yard'," he said.
"I think as a city we can do a little bit better than that."
He too claimed he was "not anti-port", saying he "love[ed] to see containers leaving that port every day".
"I think that's very valuable, but do it in a better way. There are parts of that port that could be used that give Aucklanders access to the harbour and look a hell of a lot better than it is, which is a pretty poor car yard at the minute."
Businesswoman, TV personality and former model Sara Tetro said she opposed the expansion because Ports of Auckland had not followed the proper processes.
"I'm not anti-port and I'm not anti-progress, but I am pro-process, and these guys haven't followed the process. It was extremely arrogant," she said on Newstalk ZB.
"I grew up on the harbour, like a lot of people did. It's not about big boats, it's about little boats, and it's about people enjoying the city and why we live in Auckland, and they're ruining it."
Stop Stealing Our Harbour spokesman Michael Goldwater said it was a "really important" issue for Aucklanders to get behind.
"I think people will take note," he said of the prominent Kiwis who have jumped on board the campaign. "And I think the ports need to take note, more importantly."
Auckland mayor Len Brown had promised to carry out a study of the port, and postpone any expansion until that had been completed, Mr Goldwater said.
"That study hasn't been done."
He added: "I think if they went through that process they would discover that they actually have tonnes of land there."
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- additional reporting NZME. News Service