Sports Minister Trevor Mallard has accused the opponents of the waterfront stadium of mounting a "viral" campaign against it.
The Government is backing a 60,000 seat stadium on Auckland's waterfront to host the Rugby World Cup in 2011.
But polls - including by the Herald - have turned largely against the stadium.
Mr Mallard said on National Radio he was not putting much weight on "unscientific" phone-in polls showing a public preference for Eden Park.
He said the polls may have been swayed by individuals at Eden Park's contracted engineering firm Beca and public relations firm Sweeney Vesty mounting a "viral" email campaign against the waterfront option.
"What I'm referring to is what I think can be described as unofficial action on staff's part, sending out things that contain misinformation."
One of the emails from a Beca staff member had urged people to vote against the waterfront option in phone-in polls.
Mr Mallard said Eden Park remained the "first fall-back" for the Government.
"I think it's a poor second option. I think it shows a lack of imagination. It shows a city that doesn't have a vision, but that might be what Aucklanders want," he said today on National Radio.
Mr Mallard said he had also received advice that the base of volcanic rock under Eden Park could create piling problems and that access to the site would be difficult.
Mr Mallard said he had been receiving advice from Fletcher Construction, which would build the waterfront option if it goes ahead.
But he downplayed any bias in their advice, as Fletchers were also likely to win the Eden Park contract, he said.
Eden Park development committee chairman Rob Fisher today said he would be asking Fletchers why they were advising Mr Mallard there would be problems with Eden Park.
Tests had been done on the ground under Eden Park and there were no problems.
A lot of Eden Park's design work had already been done and a timetable for redeveloping the stadium was far more achievable than one on the waterfront.
"It's at least nine months ahead of where the waterfront is and it's designed for the foundation properties which we know are there -- tested by actual drill holes," he said on National Radio.
Fletcher Infrastructure chief Mark Binns said his team had identified the volcanic rock underlying Eden Park as an issue, but had not told Mr Mallard it would cause any real problems.
He said Fletchers had not had any real access to Eden Park's latest design and had not given advice on how the proposed 360 degree design would affect access to the site for builders.
The Government has told the Auckland City Council and Auckland Regional Council to decide between the waterfront and Eden Park by November 24.
If Auckland could not make up its mind, Jade Stadium was the back-up option.
Beca declined to comment and Sweeney Vesty was not available.
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