Watercare's state-of-the-art land-based wastewater treatment facility at Mangere has undergone extensive upgrades in the past decade in response to growth in volumes and to improve environmental outcomes.
The Mangere Wastewater Treatment Plant is the result of five years of consultation and a further five years of construction. The plant’s advanced technology means the treatment cycle takes just 13 hours.
The plant no longer uses oxidation ponds to treat wastewater. New land-based technology has allowed 500 hectares of oxidation ponds to return to the Manukau Harbour and restoration of 13 kilometres of shoreline. The old secondary and tertiary treatment processes at the plant have been replaced with new technology (reactor clarifiers and ultraviolet filtration) while other areas of the plant have either been replaced or comprehensively upgraded.
Much of the operation at the Mangere plant has been computer automated. The Wastewater Business Unit has also completed a three-year programme of sophisticated computer modeling of the entire network performance.