Sand mining at Pakiri Beach has been extended for a further 14 years by the Environment Court.
In a reserved decision, the court has dismissed objections to continued mining from the Auckland Regional Council and Friends of Pakiri made on the grounds of serious environmental effects.
McCallum Bros and Sea Tow appealed to the court after the council turned down their application to take 76,000cu m of sand a year for 20 years near the shore at Pakiri.
The companies sought to renew consents to take the sand from where the water was 5m to 10m deep in the Mangawhai-Pakiri bay area.
In court, the firms disputed the claim of the council and experts that the bays formed a closed system and no new sand was coming in.
The ARC said continued extraction would eventually lead to beach and dune erosion and would spoil the significant natural character of the coastline.
But the companies said that despite huge volumes of sand having been extracted from the Pakiri inshore area over the past 85 years, no significant erosion or change to the coastline could be blamed on the extraction.
The firms sought 20-year terms because of the quality and value of the Pakiri sand, which is needed for Auckland construction projects.
It has also been used to replenish the beaches at Mission Bay, Kohimarama and St Heliers.
Judge David Sheppard said no link between sand extraction and environmental damage had been shown. He authorised coastal permits for the mining for 14 years.
ARC environment chairman Dianne Glenn said last night she was disappointed by the decision.
In December, the council paid $20 million to create a regional park at Pakiri and the dunes there have two threatened bird species - the NZ fairy tern and the NZ dotterel.
The ARC hearing drew 678 submissions about the proposal - 658 were against and 20 for.
Friends of Pakiri chairman Nick Williams said the group would consider its option of appealing against the decision to the High Court on points of law.
"We opposed mining because Pakiri is a great place for lots of people to go to and enjoy its unspoiled white sand."
The decision created an absurd situation, he said, because mining was banned in the Mangawhai part of the bay system, which was under the Northland Regional Council.
The Mangawhai Harbour Restoration Society chairman, Graham Mackenzie, said near-shore mining was disgraceful and posed a serious risk to the rebuilding of the town's sandspit.