About the MAR project
Gisborne District Council's Makauri aquifer Managed Aquifer Recharge (MAR) trial.
Project progress - April 2018
The stage one trial has proved the feasibility of MAR and we're moving to stage 2.
A trial will be conducted to provide the information needed to develop a full recharge scheme and ensure appropriate environmental safeguards are in place. It's proposed to run the stage 2 trial over 2 years – injecting up to 400,000m3/year (depending on river flows).
The information gained in the Stage 2 trial will be used to develop a full MAR scheme and enable greater water security for the horticultural sector.
Resource consent has been granted to construct 2 new monitoring bores. A resource consent variation has been lodged to increase the volumes of water abstracted from the Waipaoa River and inject into the Makauri Aquifer. The application will be subject to limited notification and a hearing is likely. Resource consent is not now expected before June 2018.
About the MAR project
Council is evaluating Managed Aquifer Recharge (MAR) as one of several tools to help resolve declines in groundwater levels and storage. MAR is a proven technology used throughout the world to actively manage the replenishment of groundwater systems. The term ‘MAR’ represents a wide range of physical, regulatory and economic tools that are used to develop and operate groundwater recharge schemes. These schemes are often most effective when MAR is integrated with other water management tools such as surface storage, water conveyance systems and planning processes where surface and groundwater resources are evaluated as part of an overall sustainable water management framework.
Newsletter updates on the project's progress
April 2017 - 2 bores have been drilled at Kaiaponi Farms Ltd. The purpose of the pilot bore is to confirm the depth, thickness and other physical characteristics of the Makauri Aquifer at the trial site.
Read more in the April newsletter [PDF, 1.4 MB]
Why are we doing the trial?
The water levels in the Makauri Aquifer are declining.
The aquifer is a much needed source of water for irrigating crops - it’s an estimated $20m value to our industry. If we have to reduce or stop irrigators taking water from the aquifer it will have a significant impact on local economy.
The aim of the trial is to see if it’s possible to use Managed Aquifer Recharge (MAR) technology to increase the water levels in the aquifer.
The trial is funded by grants from Ministry for Primary Industries and the Eastland Community Trust. Much of the total cost is the initial extensive water modelling and research with expert consultants.
A detailed business case would be completed for ongoing costs if the trial was successful.
The trial will also provide Council with other useful information about how the groundwater interacts and provides baseflow to the rivers during dry summers, and to inform water use and quality questions for our region.
Pre-feasibility assessment findings
A MAR pre-feasibility assessment for the Poverty Bay aquifer system has been completed by Golder, (an international consultancy with leading expertise in Managed Aquifer Recharge). The findings from this assessment indicate that a trial for injecting water into the Makauri aquifer has favourable conditions in which to operate, including:
A degrading groundwater storage situation has been clearly identified, together with the potential impacts on economic development and environmental sustainability in the region.
The Makauri aquifer appears ideally suited to injection and the pilot trial. The associated monitoring of effects will provide a wealth of information that will characterise the way the aquifer behaves with water injection.
Approximately 100,000 m3 of treated water is considered to be potentially available during the winter, when the city water storage dams are overflowing to support a MAR pilot trial.
A MAR pilot trial also provides an opportunity to explore the potential opportunities for MAR as part of an integrated water strategy that is sustainable for the aquifer and surface water. It will provide a comparison between options that are available to manage water source sustainability.
The proposed MAR pilot trial can sit alongside other studies, such as: A masterate thesis on the potential for using infiltration basins in the upper aquifer area to replenish groundwater and an economic study that will update earlier Ministry of Works reports that compared several storage dam sites in the foothills around Poverty Bay.
Leading on from the pre-feasibility study applications to Eastern Community Trust and to Ministry for Primary Industries have been made. Grant funds, of up to $460,000 have been secured to finance an injection well pilot.
Questions and answers
Q&As about the Makauri aquifer MAR trial