MHRS legal representative James Carnie and Richard Bull.
A map showing Kaipara’s proposed consent area in hatched red.
The Mangawhai Harbour Restoration Society (MHRS) argued that controversial sand mining near Pakiri should be shifted to the Kaipara Harbour or substituted for other sources at a hearing in the Warkworth Town Hall last week.
The hearing comes in the wake of Kaipara Ltd’s application to renew its consent to extract two million cubic metres of sand offshore from Pakiri and Mangawhai over 20 years.
It contends that Pakiri’s sand is required to prevent a shortage of supply for the production of concrete in the Auckland market.
MRHS legal representative James Carnie contested this at the hearing, saying that the Kaipara Harbour could fulfil Auckland’s sand needs.
He said the Kaipara Harbour was shown to be replenished with 2.6 million cubic metres of sand each year, providing for sustainable extraction.
He added that inland quarries already provided 66 per cent of sand used in production of concrete and could make up any shortfall.
MHRS also presented a report by environmental scientist Dr Shaw Mead, which alleged that Kaipara Ltd had breached its current consent conditions by extracting sand 1000 metres north of where it was permitted.
Mr Carnie said this explained why sand dunes at Mangawhai had been observed eroding, despite constant work to replenish them by the society.
Further, the report alleged that Kaipara Ltd had been caught extracting sand closer to shore than is permitted.
However, commissioner Les Simmons said the allegations against Kaipara were being contested and could not be considered as part of the hearing.
“This panel does not have the ability to enforce breaches. My understanding is that we are to consider the application aside from the alleged breaches,” he said.
Dr Mead’s investigation also suggested that Kaipara Ltd had been extracting as close to shore as possible within the permitted area, causing environmental damage.
Mr Carnie said Kaipara Ltd had focused extraction on an area representing less than one per cent of the total permitted area.
It is alleged that consistent extraction of a particular stretch had resulted in a kilometres-long trench on the seafloor.
Kaipara Ltd has acknowledged the formation of 7.5 kilometres of “swales”, 2.4 metres deep, and has suggested a 100-metre exclusion zone as part of the consent conditions.
But MHRS wanted more, asking commissioners to require that Kaipara Ltd extract at a minimum distance of five kilometres from shore and at a minimum depth of 35 metres, if the consent was accepted.
Commissioner Les Simmons asked Mr Carnie whether he thought the panel had the authority to require the extraction to take place outside of the area in the application.
The pair agreed that they did not know if it was legally possible.
Meanwhile, it is expected that McCallum Bros will also seek to renew its consent for nearshore sand extraction, which has expired.
Both McCallum Bros nearshore extraction and Kaipara Ltd’s offshore extraction has been undertaken by McCallum Bros’ vessel, the William Fraser.