The Government and Auckland Council are considering a "toilet tax" to pay for a $1 billion sewer tunnel.
The tax is proving controversial and would involve a change in law, and potentially raising the overall cost of the project.
Flushing money down the toilet is about to take on a whole new, very real, meaning.
Auckland Council has plans to pass the cost of waste water treatment onto ratepayers.
National MP Judith Collins has criticised the discussion.
"It seems to be a very dodgy way to go. I mean what's next - a rate for footpaths? I mean the whole thing's just bizarre."
The tax would fund the central interceptor, a 13-kilometre-long pipe from Western Springs to Māngere Wastewater Treatment Plant - an overdue project.
Auckland Councillor Daniel Newman says it comes down to pollution as well.
"We can't have our beaches and our waterways polluted with untreated waste water.
"I would argue that Watercare can absolutely afford it. They've got a conservative balance sheet, lots of head room, and the problem is, you could say, the consolidated council balance sheet is struggling."
Meaning, the council can't afford to carry the debt. In order to get around it, the Government could step in with a law change and create a Special Purpose Vehicle (SPV) that would have rating powers. The SPV would own the pipe and pass on the cost to ratepayers over the next 25 to 40 years.
"Presumably without Aucklanders having a mechanism to challenge and remove these people who are responsible for rating them for this project," says Mr Newman.
That's where the controversy comes in, because for the first time a non-elected agency would be charging rates, which is a precedent other local authorities would be extremely interested in.
"If they do it for Auckland they're going to have to do it for every other council, so for those people who live outside of Auckland who think, well it doesn't affect me, don't worry - it's coming to you" says Ms Collins.
Ms Collins says it's time the Mayor took public accountability for the cash-strapped council's financial issues.
How much further the plan gets now relies on the Government's next move. The Mayor could not be reached for comment on Saturday.