In the 1960s huge sewage oxidation ponds were built in Manukau Harbour at Māngere (left). Covering 600 hectares, they provided secondary treatment (aeration to reduce the biological content) for most of Auckland city’s sewage. By 2002 the oxidation ponds had become obsolete, and were replaced by a land-based treatment station and a small storage basin which holds treated water for release on high tides (right). Land-based treatment is of a higher standard, and takes up less space in the estuary than oxidation ponds.
Te whakamahi i tēnei tūemi
This item has been provided for private study purposes (such as school projects, family and local history research) and any published reproduction (print or electronic) may infringe copyright law. It is the responsibility of the user of any material to obtain clearance from the copyright holder.