Masterton is the only Wairarapa town with fluoridated water.
Mrs Patterson said Masterton District council followed Ministry of Health guidelines on fluoride and had no plans to change that in the foreseeable future.
A statement on the Ministry of Health website states the ministry "strongly supports water fluoridation as a safe, effective and affordable way to prevent and reduce tooth decay across the whole population".
DHBs were better placed to hold the responsibility than councils, as fluoridating water was a health issue, Mrs Patterson said.
South Wairarapa mayor Adrienne Staples shared Mrs Patterson's sentiments.
"DHBs are far more abreast of health issues and far more involved in things like the stats of health and dental care."
Mrs Staples said there were mixed feelings on adding fluoride to Featherston, Martinborough and Greytown's water supplies.
"Our council has decided not to do that [fluoridate the water] at the moment."
She said if the responsibility shifted, South Wairarapa would have to follow the law.
"If the Government want the DHB to have the say, they will have to have the legislation to do it.
"It will be up to the DHB, I guess we'll have to do as we are told."
Communities nationwide remain bitterly divided on whether to add fluoride to town drinking water supplies.
Hamilton residents voted overwhelmingly to retain fluoride last month after a heated debate saw the council remove it in July.
In Hastings, a fluoride referendum was held alongside council elections last month. Residents voted to retain water fluoridation.
Anti-fluoridation group Fluoride Action Network New Zealand has argued fluoride can be linked to adverse health effects such as arthritis, thyroid dysfunction, lowered IQ and hypersensitivity.
FANNZ national co-ordinator Mary Byrne, Featherston, has called mandatory fluoridation "via the back door".
"The DHBs are legally bound to follow the dictates of the Ministry of Health without regard to the wishes of the people in their district."
However the parliamentary health committee's report said scientific evidence was clear that adding fluoride to a town water supply in appropriate monitored doses led to a reduction of dental decay in children, particularly children living in low socioeconomic families.
It recommended health experts produce and monitor "strong scientific evidence" to back up their decisions on adding fluoride to water.
However, Health Minister Tony Ryall said fluoridation of public water supplies was a decision for local communities.
"The Government's role is to support local councils when they decide to use fluoride - not to make the decision for them - and we are not considering changing that."
Local Government New Zealand president Lawrence Yule said it would be a "huge shift" to give DHBs the power to fluoridate water supplies - though DHBs would still be accountable to voters.
"I think it probably sits better there than it does with the [councils], we have no experience about the health risks so I would probably welcome that overall."
APNZ
