Watercare is planning to spend $57.5 million to recommission a mothballed dam in Hūnua to help in the fight against Auckland's water shortages.
The Hays Creek Dam was built in 1967. It is the smallest of the Hūnua dams and was originally designed solely to supply water to Papakura. It has a lake area of 18.2 hectares and can hold 1.1 gigalitres of water.
A spokesperson for Watercare said the total cost of the Hays Creek Dam project (including integration with existing water supply network) is $57.5 million and will include the construction of a new water treatment plant.
"We stopped drawing drinking water from Hays Creek dam in 2005 because the Papakura Water treatment plant needed significant upgrades and at that time we didn't need it from a supply point of view."
While it had been out of service for the past 15 years it would help with the current crisis, they said, and could be expected to provide up to six million litres a day when it was up and running in December.
A separate new reservoir on the outskirts of Pukekohe which can handle 50 million litres of water is also scheduled to be up and running by August.
The two South Auckland projects, along with a new treatment plant at Ōnehunga, a new Pukekohe bore and plans to increase the amount of water Auckland gets from the Waikato, are expected to provide an additional 40 million litres a day to the region.
According to Watercare they will slow the decline of lake levels in Auckland's nine dams in the Waitākere and Hūnua Ranges, which normally supply about two thirds of the city's water.
"To put that in perspective, that 40 million litres a day would supply a city the size of Dunedin," Watercare chief executive Raveen Jaduram said.
Watercare said this week's rain has seen the city's dam levels increase from just under 45 percent to over 47 percent on Thursday.
A welcome respite, but still not enough to stop ongoing water restrictions. Auckland's total dam storage would normally be at about 78 percent for this time of year.
From November 2019 to May 2020, Auckland received less than half the normal rainfall, which has led to outdoor water restrictions being put in place for the first time since the 1993/1994 drought.
According to MetService meteorologist Georgina Griffiths the long-range weather forecasts for drought-stricken Auckland don't look good.
"The long-range models are sending a clear signal for a much drier-than-normal spring period, between August and November, with a strong ridge of high pressure preventing the rain makers from crossing Auckland very often.
"This is the driest outlook for the spring season we've seen since 2013, when a major drought affected the upper North Island."
In February 2020 the Minister of Agriculture Damien O'Connor declared an agricultural drought north of the Auckland Harbour Bridge and in March 2020 extended that to the rest of Auckland.
Large parts of the rest of the North Island are also experiencing both agricultural and hydrological droughts.
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