Wellington City Council is set to consider a rates rise of up to 23 percent.
Photo: RNZ / Richard Tindiller
RNZ understands a discussion document about next year's rates has been presented to councillors.
The council is working through a draft 10-year strategy and documents raise the possibility of a hefty rates rise.
But the city's mayor, Andy Foster, said no decision has been made and the council is months away from deciding on a rates increase for 2021-2022.
"This will be one of the most challenging budgets ever considered by council," he said.
Foster said it was far too early to speculate on the size of a rate increase.
The council is facing a bill for several large projects, including upgrading the city's ageing infrastructure, strengthening the central library and its plan to Get Wellington Moving.
Councillors Rebecca Matthews and Fleur Fitzsimons say that huge bill is an enormous task but necessary.
Fitzsimons said the cost should not fall on just ratepayers and other partnerships should be considered.