Fluoride in Nolensville, TN
Nolensville’s main utility treats no water of its own — it buys from three systems that each set their own fluoride level. Here is the picture, source by source.
Nolensville’s water is fluoridated — but there is no single Nolensville level. The Nolensville-College Grove Utility District buys water from three systems: Metro Nashville (0.67 mg/L), Mallory Valley (0.53 mg/L average), and Smyrna (0.492 mg/L average). Every source runs at or below the CDC 0.7 mg/L target; two run below it.
How this page works: the levels below come from the district’s own published water quality reports, presented per source — because that is how the district reports them — not from a marketing claim or a guess, and never blended into a single invented number. New to the topic? Start with our full fluoride guide.
Water quality in Nolensville
Curious about your tap water? Tennessee Water Authority has the full Nolensville water quality guide — contaminant data, utility details, and filter recommendations.
Nolensville’s fluoride, by utility
Everything on this page traces back to these facts, from each utility’s own published water quality report.
LEVEL NCGUD — Metro Nashville source
0.67 mg/L
Range 0.56–0.75 mg/L, NCGUD Water Quality Report for 2025. Essentially at the CDC 0.7 mg/L target.
LEVEL NCGUD — Mallory Valley source
0.53 mg/L average
Range 0.25–0.65 mg/L, NCGUD 2025 report. Mallory Valley water is treated by Harpeth Valley U.D. Below the CDC recommended 0.7 mg/L — stated plainly.
LEVEL NCGUD — Smyrna source
0.492 mg/L average
Range 0.453–0.580 mg/L, NCGUD 2024 report. Below the CDC recommended level — stated plainly. (No 2025 Smyrna figure is published; see the sources note.)
LEVEL Milcrofton U.D. addresses
0.53 mg/L average
Milcrofton (TN0000247, ~33,605 served) buys Harpeth Valley U.D. water — 0.53 mg/L average, range 0.25–0.65 (HVUD 2025/26 report). Below the CDC target.
STATUS Fluoridated — adjusted, by the suppliers
Every treating source adds fluoride; the CCR fluoride rows carry the source language “water additive which promotes strong teeth.” NCGUD treats no water itself — the level is set by whichever purchased source is flowing.
UTILITY Nolensville-College Grove U.D.
PWSID TN0000511. Serves about 32,335 people and purchases treated water from Metro Nashville, Mallory Valley U.D., and the Town of Smyrna. It publishes per-source fluoride figures — no blended level — so this page states none.
How Nolensville’s levels compare
Nolensville has no single level — so the table carries each verified source level, next to the three benchmarks that matter, each labeled for exactly what it is.
| Benchmark | Level | How Nolensville compares |
|---|---|---|
| NCGUD — Metro Nashville source, 2025 | 0.67 mg/L | Range 0.56–0.75 mg/L. Essentially at the CDC target. |
| NCGUD — Mallory Valley (HVUD) source, 2025 | 0.53 mg/L avg | Range 0.25–0.65 mg/L. Below the CDC recommended level — we won’t round it up to the target. |
| NCGUD — Smyrna source, 2024 | 0.492 mg/L avg | Range 0.453–0.580 mg/L. Below the CDC recommended level — about seven-tenths of it. |
| Milcrofton U.D. (HVUD water), 2025/26 | 0.53 mg/L avg | Range 0.25–0.65 mg/L. Below the CDC recommended level. |
| CDC recommended level | 0.7 mg/L | Only Metro-source water meets it. The other verified Nolensville sources run below it. |
| EPA secondary (non-enforceable) standard | 2.0 mg/L | All Nolensville levels are far below this guideline, which is aimed at preventing cosmetic effects like tooth discoloration. |
| EPA enforceable maximum contaminant level (MCL) | 4.0 mg/L | All Nolensville levels are far below the legal limit. |
NCGUD blends its three purchased sources in one distribution system and reports fluoride per source, not as a single blended level — so the level at a given Nolensville tap sits somewhere in the 0.49–0.67 mg/L band depending on which source water is flowing. The district’s 2024 report put its Metro row at 0.68 mg/L (range 0.61–0.75), consistent with 2025.
Nolensville is not one water system — and its main utility is not one source
Which level is yours depends on two things: whether your bill names NCGUD or Milcrofton U.D., and — on NCGUD — which of its three purchased sources is flowing to your street. Check your water bill for your utility’s name before assuming any single number on this page 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.
That holds across Nolensville’s whole 0.49–0.67 mg/L band — at Metro’s near-target level and at the below-target Mallory Valley and Smyrna levels alike: 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.
If your Nolensville water is running on the Mallory Valley (0.53 mg/L) or Smyrna (0.492 mg/L) sources — below the CDC recommended level — varnish remains worthwhile for kids and for adults at higher cavity risk: people with recent cavities, dry mouth, braces, or exposed tooth roots. 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 in Williamson County, where a home can be minutes from a city 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 Nolensville’s level yourself
Don’t take our word for it — the primary sources are public.
- Read NCGUD’s current water quality report. The 2025 report (PDF) lists fluoride per source: Metro 0.67 mg/L (range 0.56–0.75) and Mallory Valley 0.53 mg/L average (range 0.25–0.65); the 2024 report lists Smyrna water at 0.492 mg/L average. 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 at nccd.cdc.gov/DOH_MWF lists fluoridation status and levels for community water systems, including NCGUD (TN0000511) and Milcrofton U.D. (TN0000247).
- Check whose name is on your bill. If your bill names Milcrofton instead of NCGUD, your water is Harpeth Valley water — HVUD’s 0.53 mg/L average governs your tap.
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 — but Nolensville's main utility treats no water of its own. The Nolensville-College Grove Utility District (NCGUD) buys treated water from three systems, and all three add fluoride: Metro Nashville reported 0.67 mg/L, Mallory Valley water averaged 0.53 mg/L, and Smyrna water averaged 0.492 mg/L. Milcrofton Utility District, which serves other Nolensville-area addresses, delivers Harpeth Valley water at 0.53 mg/L average.
Somewhere in the 0.49–0.67 mg/L band if you are on NCGUD — the district blends Metro Nashville water (0.67 mg/L), Mallory Valley water (0.53 mg/L average), and Smyrna water (0.492 mg/L average, 2024 report), and publishes per-source figures rather than one blended level, so this page does not invent one. Milcrofton customers get Harpeth Valley water at 0.53 mg/L average.
Two of the three NCGUD sources are below the CDC recommended level of 0.7 mg/L — Mallory Valley water at 0.53 mg/L average and Smyrna water at 0.492 mg/L average — and this page states that plainly rather than rounding them up. Metro-source water, at 0.67 mg/L, is essentially at the target. All of them are far below both EPA standards: the secondary (non-enforceable) standard is 2.0 mg/L and the enforceable maximum contaminant level (MCL) is 4.0 mg/L.
Probably not directly. If your bill names Milcrofton Utility District, your water is Harpeth Valley-treated water at 0.53 mg/L average (range 0.25–0.65 mg/L). If it names the La Vergne Water System or Consolidated Utility District of Rutherford County — wider-area systems in the Nolensville guide — no fluoride figure for them could be verified for this page. Check whose name is on your water bill; that utility's report 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 — especially if your water is running on the Mallory Valley or Smyrna sources, at 0.53 and 0.492 mg/L, below the CDC recommended level. 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 in Williamson 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 NCGUD's current water quality report — the 2025 report is linked in the sources below and lists fluoride separately for its Metro and Mallory Valley sources, and the 2024 report carries the Smyrna figure. You can also check CDC's My Water's Fluoride, which tracks fluoridation status and levels by water system. If your bill names Milcrofton, its water is Harpeth Valley water, so HVUD's report is the one that governs your tap.
Sources & method
- Nolensville/College Grove Utility District, Water Quality Report for 2025 — fluoride (Metro) 0.67 mg/L, range 0.56–0.75; fluoride (Mallory Valley) 0.53 mg/L average, range 0.25–0.65; system TN0000511; ncgud.com — CCR 2025 (PDF).
- Nolensville/College Grove Utility District, Water Quality Report 2024 — fluoride (Smyrna) 0.492 mg/L average, range 0.453–0.580; fluoride (Metro) 0.68 mg/L, range 0.61–0.75 (as transcribed in the Tennessee Water Authority Nolensville guide’s verified-CCR section).
- Harpeth Valley Utility District, CCR 2025/26 — fluoride 0.53 mg/L average, range 0.25–0.65 mg/L; system TN0000286 — the treated water behind both Mallory Valley and Milcrofton.
- Tennessee Water Authority, Nolensville water quality guide — area utility structure, PWSIDs, and the verified NCGUD 2024 CCR transcription; tennesseewaterauthority.com/nolensville-tn-water-quality-guide.
- 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: Nolensville’s levels come from NCGUD’s own published reports, presented per purchased source because the district publishes no blended level — and none is invented here. NCGUD’s 2025 Smyrna fluoride row is scrambled in its PDF, so the clean 2024 Smyrna figure is used and labeled 2024. We never name, rank, or recommend private dental practices.