Fluoride supporters, it appeared, had everything going for them.

Five Portland city commissioners had voted to add fluoride to the city water supply. Health advocacy groups, and many of the city’s communities of color, lined up behind the cause. And proponents outraised opponents 3-to-1.

But none of that was enough. For the fourth time since 1956, Portlanders on Tuesday night rejected a plan to fluoridate city water, 60 percent to 40 percent.

Opponents successfully block move to fluoridate Portland's water

“There’s a libertarian component to Oregon politics … a kind of opposition to what the establishment might want,” said Bill Lunch, a political science professor at Oregon State University. “Those who have more money, despite the kind of popular presumptions in this regard, don’t always win elections.”

The lesser-known of two issues on the Portland ballot passed easily. Voters approved a third renewal of the city’s Children’s Levy with more than 70 percent in favor. The levy directs more than $9 million a year to programs that support about 14,000 children annually in areas such as child abuse prevention, after-school activities and foster care.

The campaign to renew the levy, however, took a back seat to the fight over fluoride, which intensified in the weeks leading to Election Day.

In Portland, where a largely Democratic electorate often finds liberal candidates struggling to differentiate themselves, the fluoride debate created stark, and heated, divisions.

Both campaigns accused the other of stealing yard signs. A thinly veiled anti-fluoride push poll went out to voters. Opponents were described as insensitive to equity issues, while proponents were accused of wanting to willingly pollute the city’s famously pure water.

The issue also wound up politicizing a statewide health report that showed falling cavity and tooth decay rates in the state over the past five years. One of the report’s authors said she felt pressured by Upstream Health, the group spearheading fluoridation, to present the findings in a certain way.

More than $1 million was spent on the campaign, a considerable total for a Portland-only election. But Portland finds itself back where it has historically been, as the only city among the nation’s 30 most populous to not approve fluoridation.

Clean Water Portland, the group leading the opposition, was hesitant to claim victory, but it was clear an hour after the 8 p.m. ballot deadline that the measure didn’t have enough support.

Still, said Kelly Barnes, a spokeswoman for the group, “when you really get down to it, clean water is a universal issue.

“When citizens took a look at the information, they decided for themselves that the risk wasn’t worth it.”

Barnes wouldn’t discuss possible next steps, although the group has said it would like a ban on fluoride written into the city charter.

“I think we’re going to take a little rest and reevaluate where we are.”

The pro-fluoride group Healthy Kids, Healthy Portland conceded defeat early. “Disappointed” was the word of the night.

“The results are certainly disappointing, but I think they’re mostly disappointing because, at the end of the day, we were not able to provide this preventative measure” to people who need it, said Alejandro Queral, co-chair of the group’s steering committee. “The issue doesn’t go away at the end of the election.”

Dana Haynes, Mayor Charlie Hales’ spokesman, said Hales had no plans to come back at the issue but shared supporters’ frustration.

“The measure lost even with my own ‘yes’ vote,” the mayor said in a statement. “Disappointing, but I accept the will of the voters.”

Portland has been at odds with fluoridation for more than half a century.

In the 1950s, residents considered the question of fluoridation about the same time many of the nation’s other large metro areas were adopting the practice as a way of fighting tooth decay. Portland voters bucked the trend and rejected the proposal. They said no again in 1962.

It seemed Portlanders had come around to the idea in 1978 when they approved a fluoridation plan. But two years later, they reversed course and voted to scrap it.

Since then, fluoridation has remained a constant political issue, on par with mandatory gas station attendants, occasionally coming up at the Legislature but never finding any traction.

That changed in September when, after a year of pro-fluoride lobbying, the Portland City Council quickly approved a plan to add fluoride at 0.7 parts per million beginning in March 2014.

The decision affected not just Portland, but 19 other cities, including Gresham, Tigard and Tualatin, that contract with the city to buy water from the Bull Run Reservoir. All told, the fluoridated water would have reached 900,000 people.

Early estimates put the project at $5 million for startup costs and $575,000 annually after that.

Opponents, however, quickly moved to get fluoride on the ballot.

In the months leading to the election, Healthy Kids, Healthy Portland focused on making the issue about equity. The group pulled together support among communities of color and raised more than $800,000 in cash and in-kind contributions. The group sold fluoridation as a scientifically sound method for fighting what they called the state’s dental crisis, continuously noting that nearly three-fourths of Americans drink fluoridated water.

Despite its financial disadvantage, however, Clean Water Portland proved better at mobilizing an electorate wary of adding a chemical to one of the nation’s cleanest sources of drinking water. Signs calling for residents to reject “fluoridation chemicals” popped up on lawns across the city even as stories in the national media popped up, poking fun at the city’s resistance to a common practice.

“The simplicity of their message was certainly an advantage,” said Queral from Healthy Kids, Healthy Portland. “I think the opponents did a very good job of casting doubt on the science. I think they homed in on their message and they hammered away on it.”

— Brad Schmidt contributed reporting to this story.

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