Waikato Regional Council's chair has called for an urgent summit to help find a "pragmatic solution" to Auckland's water crisis without it taking what it describes as a "back-door approach".
But Auckland Council and Watercare say they are double booked to have a full council meeting about the water crisis and won't be attending the meeting with just three days' notice.
Instead Auckland Council and Watercare claim they had already agreed to a date in two weeks' time to discuss the matter.
The two councils have been at loggerheads over Auckland Council and Watercare's attempts to take hundreds of millions of litres more water each day from the Waikato River to address its dire water shortage.
Auckland's current water storage levels currently sit at 53.85 per cent - 25 per cent lower than the average for this time of year.
Waikato Regional Council chairman Russ Rimmington last week slammed the council and Watercare for surprising them and taking a "back-door approach" by asking the Government to fast-track its 2013 water consult to allow it take 200 million litres a day.
Rimmington said the purpose of the urgent water summit - which he only invited Waikato River Authority, Waikato-Tainui, Auckland Council, Watercare and the Environment Minister David Parker to on Saturday night - was not to relitigate history, but to find a positive pathway to avert Auckland's water supply crisis.
But a spokesperson for Auckland mayor Phil Goff's office said the late night request had come as a surprise as it already agreed along with the chairs and chief executives of Waikato Regional Council, the Waikato River Authority, Watercare to attend a meeting in two weeks time. Waikato-Tainui's confirmation was still pending.
"Unfortunately, both Watercare and the council's governing body are having a preplanned workshop on Auckland's water crisis on Wednesday and therefore will not be able to go to Hamilton at such short notice."
However Watercare and Auckland Council were more than happy to attend on the previously agreed date or work to find a date that suited all parties, he said.
Meanwhile Rimmington said he was supportive of Watercare's most recent application lodged in May for 100 million litres per day to only be taken during high winter flows.
The previous 2013 application was to take a further 200 million litres of water for future needs and Rimmington said it could tie up the water for about a decade preventing Waikato Regional Council from allocating it to others if Auckland didn't need it.
"With this 100 million litres per day there can be more reliance on the Waikato River and in turn the use of the reservoirs can ease over winter, enabling the dams time to recover ahead of the high-demand summer months. This would increase Auckland's resilience."
Watercare is currently working on its infrastructure to allow it to treat that much water and is expected to be able to process more by August.
Waikato Regional Council chief executive Vaughan Payne said the application was on hold while it consulted with mana whenua, but he believed the May application fitted the conditions to be granted.
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