"Auckland harbour is not a motorway. It is not a roadway. It is not a cycleway. It is a waterway and enough is enough," said Dickson, who has been sailing on the harbour for 45 years.
Rugby great Bryan Williams said the beauty of Auckland's harbour was something to cherish. He did not like the idea of another 100m of encroachment into the picturesque waterway, particularly to park cars.
"I love the beaches and the harbour and the aesthetics of Auckland. I feel passionate about it," Williams said.
Auckland Council, which owns the port, granted resource consent late last year for two large wharf extensions from the end of Bledisloe Wharf. They extend out about 100m, are 33m wide and cover 7590sq m.
The port company plans to start construction next month and says it will need to reclaim 3ha of seabed between them over time.
An advertisement in today's Herald contains the open letter to the port company signed by 110 Aucklanders.
"C'mon Ports of Auckland, stop stealing our harbour!" it says.
The letter says the wharf extensions will destroy views from Queens Wharf that Aucklanders paid $40 million for, and that the eventual reclamation will be for parking thousands of cars and stacks of containers.
"We are not against Ports of Auckland operating in the city, but we are against you grabbing more space, narrowing an already congested Waitemata Harbour and blocking connections," the letter says
The Stop Stealing Our Harbour lobby group wants a stop to all expansion work until a study of the social, cultural, environmental and economic effects of the port's place in the wider city is completed.
Auckland Mayor Len Brown has declined an invitation to speak at Sunday's protest.
The port company said it had an urgent need for more berth space to accommodate longer ships, and was committed to building the berth extensions.
"The extensions will be an incredibly useful asset to the city with minimal impact on the harbour."
Sunday's protest, which will include boaties taking to the harbour, is on Queens Wharf at 3.30pm.
More details: www.stopstealingourharbour.co.nz
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