Many in Auckland are to pay significantly less for their water under a new pricing system introduced as part of the super city reforms.
Watercare Services, which provides the region's water, says a single price will apply, similar to the cheapest water now provided by seven of the present councils.
The charge will be $1.30 for every 1000 litres of water they use, compared with more than $2.30 in some parts of the region.
The biggest savings of 44% are for households in Orewa and Whangaparaoa, with 28% savings in Auckland City, 25% in Waitakere and 21% on the North Shore. Manukau City presently has the region's lowest prices and will notice little difference.
Charges for waste water are not due to change for nearly two years, and matching the different pricing systems will be more complicated.
The new Auckland Council will come into being on 1 November. It comprises eight existing councils.
Waitakere City deputy mayor Penny Hulse says while cheaper water under the super city reforms is good, she is concerned about water conservation.
At the start of this winter, Watercare Services warned Aucklanders about falling supply lake levels.
Ms Hulse says she hopes the price is not so low that Watercare cannot afford to continue conservation programmes.
However, Watercare chairman Graham Hawkins says there will be measures to encourage water savings.