Two of the Carew Storage ponds. Three ponds, covering an area of 150ha, store up to 6.1 million cubic metres (61,000,000,000 litres). It increases the reliability of the Mayfield Hinds Irrigation Scheme by supplying water when wtaer taken from the Rangitata has to be reduced. The entire area of the ponds is lined with HDPE plastic that is welded into a continuous sheet.