Architects, urban designers and boaties are lining up behind Heart of the City to oppose the port company's expansion plans.
The Heart of the City lobby group and the Auckland Architecture Association have each produced images to show the impact of the plans.
The images by the lobby group - at sea level and an elevated level - show the extension of Bledisloe Wharf by 250m and Fergusson Wharf by 50m.
Images produced by the Auckland Architecture Association show the impact of the view from the port at present and the impact from extending Bledisloe Wharf by 250m in the future.
Association spokesman Adam Mercer said that from Queens Wharf, Aucklanders could look all the way down the harbour to Browns Island and beyond, but that view would disappear if the expansion plans proceeded.
Mr Mercer said that by reconfiguring the expansion plans, the views Aucklanders enjoyed from Queens Wharf and elsewhere could be kept.
Port infrastructure general manager Ben Chrystall said the Heart of the City images were not of a standard that would be acceptable in the Environment Court, and gave a misleading impression of the visual impact of the proposed expansion.
"This is an important debate and it is disappointing to see unprofessional and unbalanced visual information being given credence."
Mr Chrystall was not shown the architects' images, which were part of a submission on the Auckland Plan.
Barry Holton, deputy chairman of the Westhaven Marina Users Association, said he was shocked to learn of the port's plans in late December.
"We are completely opposed to the plans. They will significantly narrow the entrance to the harbour and will affect tidal flows and wind patterns ... They will have a grave effect on the harbour."
Graeme Scott, of the Urban Design Forum, also views the plans with considerable concern.
"I think the port has filled in enough of the harbour already. Where do you draw the line?" he said.
Heart of the City chief executive Alex Swney said the Waitemata was the jewel in Auckland's crown.
"It's our playground as well as a commercial pathway. We all share a responsibility to enhance and protect our natural assets and pass them on as best we can to future generations."