Opponents' concerns fell into eight broad categories — the volume of the proposed take, its effect on existing bores, water quality, ecological issues, salt water intrusion, lack of consultation, inadequacy of assessment and monitoring, and cultural issues.
Independent commissioners David Hill (chairman) and Peter Callander, who heard the applications on behalf of the Northland Regional Council, including a three-day sitting in Kaitāia in March, accepted that submitters had expressed a reasonable concern the safety and security of the aquifer, which was the sole source of groundwater for communities on the peninsula.
Based on evidence from the applicant, council experts and submitters, they were well aware that the aquifer was potentially vulnerable, "due to its connection to the sea and the variable amounts of rainfall recharge related to climatic changes and the clearing and planting of forestry blocks".
Lowering groundwater levels by increased abstraction posed a risk of sea water intrusion and a risk to the ability of existing users to abstract groundwater and to the health of the Kaimaumau wetland.
However, based on technical information from the applicant and council experts, they agreed that the rate of recharge could comfortably sustain the level of abstraction proposed.
The commissioners noted that "as with many groundwater development scenarios," there was a degree of uncertainty about the magnitude of change that might occur.
"This can be adequately addressed through an adaptive management strategy, as set out in the groundwater monitoring and contingency plan, and a staged approach to taking the maximum consented volumes of water," they said.
They also acknowledged the Department of Conservation's "quite proper concerns" about the value and importance of the Kaimaumau wetland, and its national status, and fears that the proposed abstraction could affect it.
"After having regard to the actual and potential effects on the environment of allowing the proposed activity, and taking into account the relevant statutory provisions, we find that consent for the proposed activities should be granted…," they said.
They found that the proposal was consistent with the provisions of the relevant statutory document(s), and that the conditions imposed would avoid, remedy or mitigate any adverse effects.
"Any risk to or potential effect on the Kaimaumau Wetland can be averted and avoided through the adaptive management conditions imposed," they said.
The amount of water to be abstracted was well within the parameters established by the best information currently available.
The commissioners' decision — which, including conditions, can be seen at www.nrc.govt.nz/consentdecisions — is open to appeal for 15 working days.
DoC may appeal
The Department of Conservation is considering whether to appeal the decision to allow 17 applicants to take more than two million cubic metres of groundwater on the Aupouri Peninsula per annum.
The Northland Regional Council commissioners' decision is also of concern within the local community. In March We Are Water spokeswoman Karen Nikora-Kerr said not only was such a large take unnecessary, but potentially risked the continued use of shallow bores and saltwater intrusion into the aquifer.
Local people and environmental groups have also complained of a lack of consultation, and the destruction of archaeological sites, dune systems and other natural features during the applicants' avocado orchard development.
Fiona Furrell, from the Northland Environmental Protection Society, said the consent amounted to "wait and see if a worst-case scenario occurs, then try to do something about it." She also claimed that the orchard developments had destroyed an entire dune system, land had been flattened right up to a pa site, and archaeological sites had been "annihilated."