Auckland Mayor Phil Goff says the council will consider a proposal to invest a further $1.7 billion in water infrastructure.
A review of Watercare by the Water Industry Commission for Scotland (WICS), has found it performs better than other water companies but needs to invest more to reach its potential.
The report said Watercare may have to spend $4.7 billion by 2032, of which $1.7b is unbudgeted.
WICS chief executive Alan Sutherland explained the report's findings to councillors today where Watercare outlined its updated Asset Management Plan.
Goff said the council will seriously consider the recommendations but noted there are constraints on the ability by the council and council-controlled organisations, which include Watercare, to borrow more money.
The council's borrowing limit of 270 per cent of debt to revenue has risen to 290 per cent this year due to Covid, but must come back to 270 per cent or lower next year to preserve the council's cherished AA+ credit rating.
Goff welcomed the finding by WICS that Watercare is by a significant margin the most efficient and effective water provider in New Zealand.