Fluoride in Knoxville, TN
Knoxville’s water fluoridation status and level, straight from the utility’s own report — what the number means, how it stacks up against the CDC and EPA benchmarks, and what it changes (and doesn’t change) about caring for your teeth.
Knoxville’s water is fluoridated. Knoxville Utilities Board (KUB) adjusts fluoride in the water it treats from the Tennessee River, and its 2025 water quality report puts the average level at 0.57 mg/L (range 0.47–0.68 mg/L). That is below the CDC recommended level of 0.7 mg/L — close to it, at roughly four-fifths — and far below both EPA standards.
How this page works: the level below comes from KUB’s own published water quality report, not from a marketing claim or a guess. Fluoride is genuinely debated, and we won’t pretend otherwise on this page — but the starting point for any honest debate is the actual number in your water, and here it is. New to the topic? Start with our full fluoride guide.
Water quality in Knoxville
Curious about your tap water? Tennessee Water Authority has the full Knoxville water quality guide — contaminant data, utility details, and filter recommendations.
Knoxville’s fluoride, in one card
Everything on this page traces back to these facts, from KUB’s Water Quality Report 2025.
LEVEL Fluoride in KUB water
0.57 mg/L average
Range 0.47–0.68 mg/L across the year. Data year: 2025.
STATUS Fluoridated — adjusted
KUB adjusts fluoride as part of treatment. This is Knoxville’s own system treating its own water — not purchased water from another utility.
UTILITY Knoxville Utilities Board
PWSID TN0000366. Serves about 242,383 people.
SOURCE Tennessee River
Water is treated at the Mark B. Whitaker plant from the Tennessee River.
How 0.57 mg/L compares
A number by itself doesn’t tell you much. Here is Knoxville’s level next to the three benchmarks that matter, each labeled for exactly what it is.
| Benchmark | Level | How Knoxville compares |
|---|---|---|
| Knoxville (KUB) average, 2025 | 0.57 mg/L | Range 0.47–0.68 mg/L across the year. |
| CDC recommended level | 0.7 mg/L | Knoxville runs below this — close, at roughly four-fifths of the recommendation. We won’t round it up to the target: 0.57 is 0.57. |
| EPA secondary (non-enforceable) standard | 2.0 mg/L | Knoxville is far below this. The secondary standard is a guideline aimed at preventing cosmetic effects like tooth discoloration. |
| EPA enforceable maximum contaminant level (MCL) | 4.0 mg/L | Knoxville is far below the legal limit — about one-seventh of it. |
KUB’s 2023 reporting tells the same story: an average of 0.58 mg/L with a range of 0.40–0.65 mg/L. Two years of the utility’s own reports, essentially the same number.
Knox County is not one water system
KUB’s 0.57 mg/L describes KUB customers — it does not describe all of Knox County. Karns, served by West Knox Utility District, runs lower, around 0.35 mg/L recently. First Utility District runs about 0.546 mg/L. Hallsdale-Powell Utility District is a separate system again. Knoxville addresses can sit on any of these, so check your water bill for your utility’s name before assuming this page’s number is your number.
Do you still need fluoride toothpaste?
Yes — and this is the point people most often get backwards.
Fluoridated drinking water is background exposure. Every glass of water bathes your teeth in a low level of fluoride, and that steady, low-level contact genuinely helps enamel resist acid. But it is a base layer, not the main event. Fluoride toothpaste delivers a much more concentrated dose directly onto the enamel, twice a day, right where decay starts.
So even in a fluoridated city — and Knoxville is one, at 0.57 mg/L — brush twice daily with fluoride toothpaste. If you have been skipping fluoride toothpaste because “it’s in the water anyway,” the water was never carrying that load on its own.
Fluoride and kids: the amounts matter
Young children swallow toothpaste, so the ADA’s guidance is about using the right small amount — not about avoiding fluoride toothpaste.
UNDER 3 A rice-grain smear
For children under age 3, use a smear of fluoride toothpaste about the size of a grain of rice. That tiny amount is deliberate — it protects the teeth while keeping what gets swallowed to a minimum.
AGES 3+ A pea-size amount
From age 3 up, a pea-size amount is enough. A ribbon of paste running the length of the brush is several times more than a child needs.
- Supervise brushing. An adult should be watching (and helping) until a child can reliably spit and rinse on their own.
- Teach spitting, not swallowing. Spit the toothpaste out when done; swallowing it as a habit is what the small amounts are designed to guard against.
- Don’t load the brush. More paste does not mean cleaner teeth — it mostly means more swallowed.
What about fluoride varnish at the dentist?
An in-office fluoride treatment or varnish is a much stronger, targeted dose than anything in tap water or toothpaste.
At Knoxville’s 0.57 mg/L — close to the CDC recommended level, but below it — varnish remains worthwhile for kids and for adults at higher cavity risk: people with recent cavities, dry mouth, braces, or exposed tooth roots. That is not alarmism; it is just arithmetic. The water gives you a partial base layer, and varnish tops it up exactly where a clinician can see it’s needed.
If your cavity risk is low, it’s also reasonable to ask your dentist to walk you through your risk before a treatment — in either direction, the decision should be explained, not automatic.
On a private well? None of this applies automatically
Well water is not fluoridated by any utility
Nobody adjusts the fluoride in a private well — or tests it, unless you do. Well water may carry naturally occurring fluoride, almost none, or more than you’d expect, and taste won’t tell you. This matters on Knox County’s rural edges, where a home can be minutes from a KUB main and not connected to it. Test your well water before assuming what’s in it, and tell your dentist you’re on well water so your fluoride plan is built on your actual water, not the city’s.
How to confirm Knoxville’s level yourself
Don’t take our word for it — the primary sources are public.
- Read KUB’s current water quality report. The KUB Water Quality Report 2025 (PDF) lists fluoride with its average (0.57 mg/L) and range (0.47–0.68 mg/L). A new report comes out each year; the newest one is the one to trust.
- Check CDC’s My Water’s Fluoride. The CDC’s system-by-system tracker lists fluoridation status and levels for community water systems, including KUB (TN0000366).
- Check whose name is on your bill. If your bill names a utility district instead of KUB, that district’s report governs your tap — not this page’s 0.57 mg/L.
For the bigger picture — how fluoridation works, the arguments on both sides, and how to think about filters — see our full fluoride guide.
Questions people actually ask
Asked the way people actually ask them — answered from the sources cited below.
Yes. Knoxville Utilities Board (KUB) adjusts the fluoride in the water it treats from the Tennessee River at the Mark B. Whitaker plant. KUB's Water Quality Report 2025 puts the average level at 0.57 mg/L, with a range of 0.47–0.68 mg/L across the year.
It is a bit low compared to the target, but not by much. The CDC recommended level is 0.7 mg/L, so Knoxville's 0.57 mg/L sits below it at roughly four-fifths of the recommendation. It is nowhere near the EPA limits — the enforceable maximum contaminant level (MCL) is 4.0 mg/L and the secondary (non-enforceable) standard is 2.0 mg/L. Brushing with fluoride toothpaste covers the rest of what your teeth need.
No — not necessarily. Knox County has several separate water systems with different fluoride levels. Karns, served by West Knox Utility District, runs lower, around 0.35 mg/L recently. First Utility District runs about 0.546 mg/L, and Hallsdale-Powell Utility District is a separate system again. A Knoxville address can sit on any of these, so check your water bill for your utility's name and read that utility's water quality report — it is the one that governs your tap.
Yes. Fluoridated drinking water is background exposure — it bathes your teeth in a low level of fluoride through the day, which helps, but it does not replace the concentrated fluoride that toothpaste delivers directly to the enamel while you brush. Brush twice a day with fluoride toothpaste, and treat the water as a helpful base layer, not the whole defense.
The ADA's guidance: for children under age 3, use a smear of fluoride toothpaste about the size of a grain of rice. For ages 3 and up, a pea-size amount is enough. Supervise brushing, teach your child to spit the toothpaste out rather than swallow it, and remember that more paste on the brush does not mean cleaner teeth — the small amounts are deliberate, because young kids swallow some no matter what.
For many people, yes. Knoxville's water at 0.57 mg/L is close to but below the CDC recommended level, so the water alone is not the full story. An in-office fluoride treatment or varnish puts a much stronger dose directly on the teeth, and it remains worthwhile for kids and for adults at higher cavity risk — people with recent cavities, dry mouth, braces, or exposed roots. If your cavity risk is low, ask your dentist to explain your risk either way rather than accepting or skipping it on autopilot.
No utility fluoridates private well water — nobody adjusts it at all. Well water can contain some naturally occurring fluoride, a lot, or almost none, and you cannot tell by taste. If your home is on a well, especially on the rural edges of Knox County, have the water tested before assuming anything about its fluoride level, and tell your dentist you are on well water so your fluoride plan reflects it.
Start with KUB's current water quality report — the 2025 report is linked in the sources below, and fluoride is listed with its average and range. You can also check CDC's My Water's Fluoride, which tracks fluoridation status and levels by water system. If your bill names a utility district instead of KUB, that district's report is the one that governs your tap.
Sources & method
- Knoxville Utilities Board, Water Quality Report 2025 — fluoride average 0.57 mg/L, range 0.47–0.68 mg/L; system TN0000366; kub.org/uploads/WQR_2025_FINAL_EE_Version.pdf.
- Knoxville Utilities Board, 2023 reporting — corroborating fluoride average of 0.58 mg/L, range 0.40–0.65 mg/L.
- EWG Tap Water Database (cross-check) — the EWG figure for KUB, 0.576 ppm, agrees with KUB’s own reported averages: two independent records, same answer.
- CDC — recommended fluoride level of 0.7 mg/L for community water systems; fluoridation status and levels are also tracked in CDC’s My Water’s Fluoride.
- EPA — enforceable maximum contaminant level (MCL) of 4.0 mg/L and secondary (non-enforceable) standard of 2.0 mg/L for fluoride in drinking water.
- American Dental Association (ADA) — children’s toothpaste amounts: a rice-grain smear under age 3, a pea-size amount at ages 3 and up, with supervised brushing.
Method in one line: Knoxville’s level comes from the utility’s own published report and is cross-checked against an independent database before it appears here. Neighboring Knox County systems are described only at the level their own reporting supports. We never name, rank, or recommend private dental practices.