A mothballed dam in the Hūnua Ranges will start supplying six million litres of water a day to the Auckland network from next week as part of a $68 million dollar Watercare project.
The Hays Creek Dam was completed in 1967 and can hold 1.1 gigalitres of water. It is the smallest of the Hūnua dams and was originally designed solely to supply water to Papakura.
In June 2020 Watercare announced it planned to upgrade the dam and build a new water treatment plant in nearby Red Hill so it could reintegrate it into the Auckland water supply network.
It said it had stopped drawing water from the catchment in 2005 because the Papakura treatment plant needed to be upgraded and at the time it wasn't seen as necessary for Auckland's water supply.
It said while it had been out of service for the past 15 years, it would help with the region's drought when it was up and running.
Watercare head of operations Priyan Perera said work on the project started in August.
Perera said stage one of the works involved a temporary water treatment plant in Red Hill taking water from the Hays Creek Dam, as well as a pipeline to connect it to the network. They are both expected to go live next week.
"That will provide six million litres of water a day," he said.
Stage two will boost capacity further
Stage two is a larger, permanent water treatment plant that will start operating from the end of the year and produce 12 million litres per day.
Perera said the work was being done in stages so Aucklanders can access the water sooner.
He said the new treatment plant is one of the most advanced of its kind in the country.
In February 2020, an agricultural drought was declared north of the Auckland Harbour Bridge and in March it was extended to cover the rest of the city. It was the longest dry spell on record for the City of Sails and saw the lake storage levels drop to just 42 percent by May.
But despite the introduction of water restrictions, according to Watercare, even a continued dry spell no longer poses the same risks which led to the crackdown in autumn.
While the city's storage dams have continued to decline, new water sources are now bolstering supplies, and consumption is 10 percent lower than a year ago.
Auckland storage lake levels are still more than 20 percent below where they normally would be, but a $224 million funding package has allowed Watercare to re-commission smaller disused water sources like the Hayes Creek Dam.
That, coupled with an agreement to increase the water Auckland gets from the Waikato River by 50m litres a day has meant a larger water crisis has been averted.
Other projects which are part of the Auckland drought response include a Waikato water plant and boost pump station ($145m), Pukekohe water treatment plant and works ($7m) and upgrades to the Waitakere and Onehunga water treatment plants ($4m).
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