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Work began yesterday on a $50 million sewer project to help boost water quality at Auckland City beaches and harbours.
The project will see 935 properties Kingsland, Eden Terrace, parts of Mt Eden and Morningside separated from the combined drainage system.
It is one of 30 projects planned over 20 years designed to prevent an estimated two billion litres of polluted water overflowing into the harbour every year.
Metrowater chief executive Jim Bentley said the Kingsland plan would help reduce an estimated 70 million litres of polluted water overflowing every year into the Waitemata harbour around the Western Bays by 2011.
"As the city continues to grow, we need to consider the future sustainability of our water and wastewater services," Mr Bentley said. "This is a vital investment in reducing Auckland City's environmental footprint."
The 20-year investment plan by Metrowater and Auckland City Council is aimed at modernising the city's ageing combined drainage systems (meaning wastewater and stormwater flowing through the same pipe).
The combined pipe network is already unable to cope at times of heavy rain, resulting in overflows including diluted raw sewage into open waterways, streams and harbour waters.
With about 15 per cent of Auckland City's drainage system currently combined, Mr Bentley said a "do nothing approach" based on current 20-year growth projections would see more than two billion litres of polluted water overflow into the harbour annually.
The sewer separation work is expected to close 30 overflow points.
