Aupōuri Aquifer consents granted

1 Sep 2021, 8:08 AM

Independent commissioners have granted two dozen consent applications by mainly Far North avocado growers to take millions of litres of water to irrigate their crops subject to a raft of conditions designed to protect the aquifer resources they will be taking water from.

In a lengthy and complex decision running to dozens of pages, Independent Hearings Commissioner David Hill (Chair) and Peter Callander grant the applications to the Northland Regional Council (NRC) by 22 people referred to as the Aupōuri Aquifer Water User Group (AAWUG).

The total volume of groundwater being sought by the applications was 4,606,260 cubic metres annually, expert evidence suggesting that was only 1.9% of the estimated 238 million cubic metres that is used by NRC to allocate water from the overall Aupouri aquifer system.

Similarly, the proposed groundwater take was only 0.16% of the estimated 2850 million cubic metres of groundwater stored within the aquifer in an average year.

(In the end the Commissioners granted a total of 4,519,984 cubic metres a year.)

At the time when submissions closed, on 1 November 2019, 113 submissions were received – 92 opposed; seven neutral; two in support, and 12 non-specific. (Eighteen late submissions were received and NRC had accepted those.)

Key issues raised in submissions included long-term impacts on the aquifer, effect on existing bores, water quality and contamination, ecological impacts, salt water intrusion, cultural considerations and a number of other issues.

“We acknowledge the concerns raised by many submitters regarding the risks of these applications abstracting too much water creating risks to surface waterways, lakes, wetlands, drinking-water wells, causing subsidence or threatening the whole viability of the Aupōuri Aquifer.” “These are all valid issues that must be guarded against.”

However, the commissioners said while the sum total abstraction sought was large in terms of quantity, “the evidence clearly indicates that it is relatively small in comparison to the annually available ‘throughput’ of the aquifer and is sustainable from that point of view”.

“Furthermore, we are satisfied on the evidence that any localised connectivity between the (aquifer) layers can be adequately monitored in real time with appropriately peer reviewed and set trigger levels that will alert parties and council to unanticipated variations in groundwater level in sufficient time to avoid adverse surface effects.”

While the applications did justify the quantities of water set out in their decision, the commissioners set conditions whereby ‘regular checks are made on the way in which the water is used to ensure that occurs in a proper and efficient manner and the submitter concerns around water “value banking” negated’.

The commissioners’ view was that the staged development of the aquifer and a required ‘trigger level’ system would manage the effects on the resource to address the uncertainties that are of significant concern to many water users and their technical advisers

Two independent review panels would also be established. One, made up of two irrigation experts, would ensure that water is used efficiently and not in a wasteful manner.

“If their assessments show that the quantity allocated to users in these consents is more than what is reasonably required to meet the water demand in 9 years out of 10, then they should recommend to NRC that a reduction in water allocation should occur.”

Similarly, a second independent review panel will review the monitoring information of effects on the water resources (including pumping tests) to ensure that no unacceptable adverse effects are occurring.

This panel will comprise a hydrogeologist and an ecologist, to “adequately cover concerns regarding wetlands”.

“They can make recommendations to NRC if changes are required to the monitoring regime, to the trigger level values, or if reductions in abstraction rates are required to avoid unacceptable effects.”

“Both these review panels must confirm that acceptable effects are occurring before consent holders can progress to their next stage of development.”

As granted, the consents run for 12 years until November 2033, which coincides with the expiry dates of the previously granted MWWUG groundwater take consents. This will allow for a comprehensive review of the aquifer to be undertaken when the renewals are made, if sought, and any emergent effects to be taken into account based on the comprehensive monitoring data collected during the term of the consents.

The commissioners’ decision is open to appeal for 15 working days.