A $28 billion price tag has been put on maintaining New Zealand's water supply and waste water disposal.
The total figure is calculated from 2009 council plans identifying the cost of capital and maintenance work required on the water system over the next 10 years.
A spokesperson for the lobby group Water New Zealand, Murray Gibb, says councils may need to borrow in order to maintain a working water system.
Mr Gibb says New Zealand's use of domestic water is significantly higher than most other countries.
