This may cause problems if the vote is closely run, said Mr Wilson, a vocal supporter of water fluoridation.
"It would be a full council that would decide and that's made very easy if there's a clear majority, it becomes slightly less clear if it's a 50/50 split," he said.
Mr Wilson described the situation as "that's democracy", and said: "It would be an ill-advised council who would ignore the clear majority of a public decision."
Council will meet this week to discuss the wording on the referendum ballot papers, something which is also likely to provoke "a lot of heat", Mr Wilson said.
He also defended the estimated cost of the fluoride referendum, saying $12,000 is much cheaper than the $120,000 it would cost to hold if it had not been called alongside local elections.
APNZ pd