The Nelson City Council has narrowly voted to raise the issue of fluoridation with the district health board despite one councillor calling the move “bizarre”.

Councillors were deliberating on the draft annual plan and have no responsibility for deciding on fluoridation, which the Government has said it intends to hand to DHBs. But it had received 45 annual plan submissions opposing any plans to fluoridate the water supply and last week it heard from a string of anti-fluoride citizens.

On Wednesday they were  supplied with new information from the staff saying if the council were responsible for fluoridating Nelson’s water, they estimated a one-off $250,000 capital cost and operational costs of $80,000 a year.

The council has already sent the written submissions to the DHB and councillors were told in writing that staff would also send the minutes of hearings and encourage the board to engage with the community on this issue.

This was not enough for councillor Ruth Copeland. She wanted the council to express the concerns of the submitters to the board at its May 24 meeting, specifically the potential cost to ratepayers of water treatment and infrastructure changes, the discharge of fluoride to the environment and its unknown long-term effects on the water catchment, and the lack of opportunity for a public “interface” with the board’s process.

Her motion was seconded by councillor Gaile Noonan and led to a spirited debate and a series of amendments.

Copeland said fluoridation wasn’t on the DHB’s May 24 agenda but she was going to make sure that it was put there.

“There’s an opportunity there for the council to present.”

She told Mayor Rachel Reese that she hadn’t yet arranged the presentation but was aware of the meeting and the opportunity for the council to speak at the public forum.

“I think it’s our obligation as leaders of the city to convey the concerns of the submitters, given that they don’t have that same option to interface with the DHB.”

Councillor Luke Acland said he was sure that all the people who’d submitted to the council would “wander up” to the DHB on May 24 and present the same viewpoint.

“It does strike me as bizarre that we’re even getting involved in this … I want to make it expressly clear that this is not a viewpoint of council … and we wouldn’t be providing any such feedback without any consultation with our community on this issue.”

It later emerged that Copeland’s intentions weren’t clear and at one point Reese asked: “What’s going on here, councillor Copeland?”

“What makes it possible for council to speak to the DHB? You’ll have to explain what’s going on.”

Copeland said several of the submitters had made it plain that they were not able to be heard by the DHB.

The mayor said she’d relied on Copeland’s earlier statement that there was a public forum opportunity.

“Now I want that clarified.”

It wasn’t, at least not publicly, but after the lunch break Copeland withdrew her motion. She said she wanted to personally submit to the DHB and was told that meant she shouldn’t vote on a new council motion.

After a moment’s reflection she decided she wouldn’t make a personal submission after all and rejoined the debate.

Noonan then moved that the council ask to be heard at the DHB meeting, to express the concerns of the anti-fluoride submitters, noting that it was not feedback on the council’s position, “the point of concern being the lack of opportunities for public interface with the DHB”.

Reese was her seconder. She said the council was just giving feedback on what it had heard in the chamber, “and I’d like them to be aware of that”.

Deputy mayor Paul Matheson spoke in favour, saying he hoped the issue of cost would also arise.

Acland said he was “hugely opposed”.

“Having not consulted in our draft annual plan on this issue, we’re now taking up the cause of submitters on something completely irrelevant to the business of this council.”

The motion was passed on a division. For: Reese, Copeland, Noonan, Matheson, Mike Ward, Kate Fulton. Against: Acland, Ian Barker, Matt Lawrey, Brian McGurk, Pete Rainey. Councillor Tim Skinner was absent for the vote – at the dentist – and councillor Eric Davy had put in an apology.