Mr Wagener said every bore was monitored by the Northland Regional Council, and the existing take did not appear to be having any effect on the aquifer's water level, although the view that the current take was "probably sustainable" was a "best guess".
"We need an assurance that the figures that are being bandied about are credible," he said.
Ian Broadhurst, who has been growing avocados for 30 years, and a spokesman for the Waiharara/Motutangi applicants, said current and future avocado growers were not going to spend a lot of money if they thought they might run out of water or contaminate the aquifer with salt water.
The group had applied for what the NRC said could be taken, the 16,775 cubic metres representing what would be needed in a one in 10-year drought. Outside severe drought conditions, growers would not use a fraction of what was being applied for.
"We don't want to rape and pillage the peninsula," Mr Broadhurst said.
"We live here too. We have as much at stake as you do."
Avocado growers, he added, spared no effort in mitigating water loss, if only to reduce the cost of a "very expensive business".
All the work done to date indicated that the requested take would be sustainable, he said, adding that while the group was reliant on NRC advice, in 30 years of growing avocados he had never seen the aquifer level fall.
Regional councillor Mike Finlayson said the Aupouri aquifer was one of the most studied in the country. Current consents allowed for the taking of around 12,000 cubic metres daily, which he believed was sustainable, although he did not know how much more the aquifer could yield.
Meanwhile, some expressed concerns regarding the avocado industry generally and its expected expansion. One said orchards tended to be corporate-owned, and in time would no doubt be sold to "the Chinese".
"It will be people living in this community who will be working those orchards," Mr Broadhurst replied.
He also rejected claims the industry was responsible for chemical and other damage to Houhora Harbour.
