A Waiheke Island local board member was among a group of six protesters who has spent the afternoon in police cells.
Police dragged a dozen people from the water during a protest over the arrival of two prefabricated units at a building site at Wharetana Bay, of which six were arrested.
Some residents, including neighbours, don't want any development within the coastal yard at Wharetana Bay which they say is archaeologically, historically and culturally significant.
They are also angry about a perceived "lack of transparency" by Auckland Council who they believe should have notified the public of the development.
Local board member Paul Walden, who had voted against the transit permit, was one of those arrested.
"Police had to wade into the water to arrest us. It was completely unprecedented," he said.
"They had absolutely no right trespass anybody because it was a public beach."
Protesters spent a few hours in the police cell before being released without charge.
Walden said police treated them well, even offering cups of coffee.
Although the group failed to halt the development, Walden said he hoped developers got the message that their precious coastline was protected.
Auckland Council publicly notified the closing of the reserve from 12am to 6pm to allow the units to be transported, yet protest organisers said it was only the Waiheke Local Board which had to power to limit access to a reserve on the island.
"The Waiheke Local Board has not done this and any closure of the reserve or subsequent trespassing of protesters [is] illegal," organisers said.
Board chairwoman Faye Storer said the board was not able to stop the "sad and sorry saga".
Auckland councillor Mike Lee and Green MP Denise Roche are among those against the development.
Roche turned up to support the protesters.
Drumming and waiata greeted the barge from 3.30am. Protesters gathered before dawn and by day-break several had slipped through the fence and stood waist deep in the sea and the chilly rain in front of the SeaLink barge that was about to dock.
Former Rainbow Warrior crew member Susi Newborn was one of several protesters to be carried back through the fence by police.
"It's Heritage Week and we are protecting our heritage just like Auckland Council wants us to," she said.
"But where's Len Brown?"
Historian Paul Monin described it as "the saddest day for Waiheke Island".
- Auckland Now
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