Most drinking water in Oregon does not contain added fluoride. Only about 26% of Oregonians served by community water systems receive fluoridated tap water, compared to a national average above 72%, which ranks Oregon 49th out of the 50 states and Washington, D.C.1Centers for Disease Control and Prevention. 2020 Water Fluoridation Statistics Whether your household gets fluoride comes down to which water system serves your address.
Which Oregon Cities Add Fluoride
Oregon leaves the fluoridation decision to each community and water provider. As of the most recent state data, 37 community water systems add fluoride, together serving roughly 915,000 people.2Oregon Drinking Water Services. Community Water Systems Adjusting Fluoride
Larger cities on that list include Salem, Corvallis, Albany, Beaverton, and The Dalles. The Tualatin Valley Water District, covering much of the Portland metro’s western suburbs, also fluoridates, though the Metzger area is excluded. Smaller communities that fluoridate include Silverton, Florence, Coquille, Seaside, and Monmouth, among others.2Oregon Drinking Water Services. Community Water Systems Adjusting Fluoride
Portland does not. It is the largest U.S. city without fluoridated water, which is a large reason Oregon’s statewide rate sits so low.
How to Check Your Own Tap Water
If you’re on a community water system, the fastest answer is your Consumer Confidence Report. Federal law requires every community water system to deliver this annual water quality report to customers by July 1, covering the previous calendar year; systems serving 10,000 or more people must deliver a second report by December 31.3eCFR. 40 CFR 141.155 – Report Delivery, Reporting, and Recordkeeping The report lists detected contaminants, including fluoride, with concentration levels. Your utility’s contact information is usually printed on your water bill.
Two other tools help. The Oregon Health Authority’s drinking water portal at yourwater.oregon.gov lists which systems fluoridate.2Oregon Drinking Water Services. Community Water Systems Adjusting Fluoride The CDC’s “My Water’s Fluoride” tool lets you look up data by Oregon county and water system.4Centers for Disease Control and Prevention. My Water’s Fluoride – Oregon The CDC database depends on voluntary state reporting and isn’t real-time, so your local utility remains the most current source.
What the Fluoride Level Should Be
The U.S. Department of Health and Human Services recommends a fluoride concentration of 0.7 milligrams per liter (mg/L) in community water for preventing tooth decay while limiting the risk of dental fluorosis in children.5U.S. Department of Health and Human Services. HHS Recommendation for Fluoride Concentration in Drinking Water for Prevention of Dental Caries Oregon systems that fluoridate target this level.
Oregon caps fluoridated water at 2.0 mg/L, which is stricter than the federal Maximum Contaminant Level of 4.0 mg/L. Water suppliers that add fluoride must submit equipment plans and operator qualifications to the Oregon Health Authority for approval before starting, test fluoride daily once operating, and file monthly records with OHA.6Legal Information Institute. Oregon Administrative Code 333-061-0085 – Supplemental Fluoridation
Even in communities that don’t add fluoride, some occurs naturally in water as it moves through rock and soil. Levels depend on local geology, and well water tends to vary more than surface water. In most of Oregon, natural fluoride sits well below the 0.7 mg/L target. Testing is the only way to know for sure.
Private Wells
If your water comes from a private well, community fluoridation data does not apply. Private wells are not regulated by the EPA or the Oregon Health Authority the way public systems are, and fluoride content depends on your local geology.
Oregon recommends that well owners test annually for bacteria and nitrate, and every three to five years for arsenic.7Oregon Health Authority. Testing Recommendations – Domestic Well Safety Fluoride is not on that standard list, but a certified lab can add fluoride to a routine potability test if you request it. This is worth doing if you have young children, or if you want to know whether the household should be taking supplemental fluoride.
If a well tests above 2.0 mg/L, standard carbon and pitcher filters won’t help; fluoride ions are too small for those systems to capture. Reverse osmosis systems, activated alumina filters, and ion-exchange resin filters can reduce fluoride. Activated alumina works best at slower flow rates, and ion-exchange resins need periodic regeneration.
Getting Fluoride When Your Water Doesn’t Have It
Roughly three out of four Oregonians on public water don’t get fluoride from the tap, so most residents rely on other sources for dental protection. Fluoride works two ways: topically, applied directly to teeth already in the mouth, and systemically, ingested so it becomes part of developing teeth. Both prevent decay, and topical sources can cover much of the gap.
Fluoridated toothpaste is the most accessible option. Brushing twice daily strengthens enamel through remineralization, which can reverse early decay and make tooth surfaces more resistant to acid. Professional fluoride varnish, applied by a dentist or hygienist, is a more concentrated topical treatment; schedules commonly run every three to twelve months depending on cavity risk.
For children between six months and 16 years old who are at high risk for cavities and whose primary drinking water is low in fluoride, a dentist or pediatrician can prescribe fluoride supplements. These are ingested and incorporate into developing teeth while also providing topical benefit through saliva. The prescriber needs to know your water’s fluoride level to set the right dose, which is another reason to pull your utility’s report or test your well.
A 2024 Court Ruling Worth Watching
In September 2024, a federal judge in California ruled in Food & Water Watch, Inc. v. EPA that fluoride in drinking water at the recommended 0.7 mg/L concentration poses an unreasonable risk of reduced IQ in children, and ordered EPA to begin a rulemaking process under the Toxic Substances Control Act to address that risk.8U.S. Environmental Protection Agency. Fluoride in Drinking Water
The ruling did not ban fluoridation or immediately change any existing standard. EPA has discretion in how it responds and announced an accelerated review of the public health risks from fluoride in drinking water following the decision.9U.S. Environmental Protection Agency. EPA Announces Next Step in Gold Standard Review of Fluoride to Inform Protective Action Any new federal rule could affect the 37 Oregon systems that currently fluoridate.