Auckland water shortage crisis over

11:32 am on 3 April 2017

Auckland's water supplier is now confident it can meet the city's normal demand and is ending calls for residents to conserve water.

The Ardmore water treament plant

Ardmore water treatment plant is operating at 70 percent capacity. Photo: Supplied / Watercare

The main water treatment plant at Ardmore was swamped with silt and debris from slips into the Hunua storage lakes during torrential rain early last month, knocking it back to half its processing capacity.

The council-owned water company, Watercare, asked residents to cut water use by 20 litres a day or risk a boil water notice.

Spokesperson Mark Bourne said this morning the company had been increasing the capacity of the Ardmore plant gradually over the past few weeks.

It was now operating at 70 percent capacity and, together with the city's four other plants, was producing 100 million litres above what was being used each day.

Watercare did not foresee any issues with the further wild weather expected this week.

Cosseys Dam

Torrential rain in early March caused massive slips in the Hunua Ranges, filling the city's water supply dams with silt, including Cosseys Dam (pictured). Photo: WaterCare

Mr Bourne said Auckland's water system was resilient but the volume of rain that fell on 7-8 March was unprecedented.

"Two months' rainfall in 12 hours would test the best infrastructure in the world."

The company was working with Auckland Council to identify measures for managing slips in the Hunua Ranges and investigating how could adapt its Ardmore plant so it can treat water with high levels of silt more easily.

Mr Bourne said Watercare will invest more than $1.9 billion over the next 10 years on water infrastructure.

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