Auckland's water management company Watercare has been granted consent to take an extra 100 million litres of water daily from the Waikato River.

It comes amid fears of a severe water shortage following Auckland's worst recorded drought and the prospect of looming water restrictions this summer.

In a statement tonight, Waikato Regional Council said it had granted two consents allowing Watercare to maximise the amount of water it can treat for Aucklanders now and into the future.

With the river currently above median flow, Watercare already has consents to take 175 million litres a day (MLD) from the river, which is the maximum its Waikato Water Treatment Plant in Tūākau can currently treat and deliver.

An application Watercare lodged in May for an additional 100 MLD has now been granted by Waikato Regional Council. It enables Watercare to take the extra water between May and September (inclusive), and at other times of the year when the river is above median flow.

Waikato Regional Council has also granted consent for Watercare to use the 25 MLD shared by Hamilton City Council.

"This is a real example of local solutions being created by local people," said Waikato Regional Council chief executive Vaughan Payne.

"My staff have been working closely with Watercare on a workable resolution since late last year. It's good to see Watercare engaging well with tangata whenua, which has enabled this significant progress to be made in line with two actions identified in the relationship agreement," Payne said.

In the past week Waikato Regional Council, Watercare, Auckland Council and Waikato-Tainui have signed a relationship agreement, with Waikato River Authority to consider it over the next few days, committing all parties to work together to protect the river and the people it provides for in both the Waikato and Auckland regions.

Watercare chief executive Raveen Jaduram said while the 100 MLD application was lodged in May this year, work to prepare the application began in November 2019.

"We lodged the application for a seasonal take of 100 MLD to give us confidence to invest in infrastructure that will enable us to treat more water from the Waikato River.

"With this consent in place, we are able to move full steam ahead with building an additional treatment plant on our existing site in Tūākau."

The consent covering the 25 MLD Hamilton City Council is sharing with Watercare on a temporary basis means Watercare can continue to treat up to 175 MLD at the current plant year-round, regardless of the river flow.

Payne said a robust process has been followed in preparing this consent.

"We needed to agree a process which would give the public and other water users confidence that Watercare's agreement with Hamilton City Council didn't result in more water being used than was actually available."

Jaduram said the agreement with Hamilton City Council was particularly valuable to Aucklanders in the short term, as the city recovers from this year's drought.

"Our total dam storage level is currently 67 per cent, where normally it would be nearing 90 per cent at this time of year. We are working hard to bring on new water sources for Auckland by Christmas. To be able to use the extra 25 MLD from Hamilton City Council regardless of river flow puts us in a strong position over summer, when water consumption traditionally goes up."

Jaduram resigned last month after he came under pressure over Auckland's water crisis. He finishes up on October 31.