Clean alpine water from the Rangitata River is delivered to the MAR site via irrigation races and pipes. The silts carried by the water settle in the forebay before the water flows through to the main infiltration basin. From there, the clean water seeps down to recharge the groundwater system.
The entire system is carefully monitored for water quality, quantity and ecological health.
Water is not recharged during times of significant rainfall to reduce the risk of lowland flooding and when there is a high demand for water, recharge operations stop.
The trial’s first official report (late August 2017) showed groundwater levels around the trial recharge site had risen around five metres and nitrate concentrations decreased.By the conclusion of the third year of operations the project had increased the number of active recharge sites from one to twelve and increased the annual recharge volume from 1.85 million cubic metres to 6.15 million cubic meters.