We read 24 results from Boone County Pwsd 9’s 2025 water quality report. No results over a legal limit; 7 above a health goal or guideline.
Serves about 15,035 people · Water system ID MO3024058 · Read the district’s 2025 report (opens in a new tab)
Open this district in the water lookupCompare with your own test results, see the district map and get matched filters.
Results from the 2025 report
Each number is copied from the district’s report and links to the page it’s printed on. Where the report lists several plants, wells or purchased water, the highest is shown.
| Contaminant | Result | Health goal | Legal limit | What it means |
|---|---|---|---|---|
| Arsenichighest measured · range ND to 3.16 · sampled 2024 · 2025 report, page 2 | 3.16 ppb | 0.004 ppb | 10 ppb | Above the health goal790x the health goal |
| Fluoridehighest measured · range 0.42 to 1.3 · sampled 2024 · 2025 report, page 2 | 1.3 ppm | 1 ppm | 4 ppm | Above the health goal1.3x the health goal |
| Gross alpha (radioactivity)highest measured · range 7.6 to 10.8 · highest of 2 sources · 2025 report, page 2 | 10.8 pCi/L | 0 pCi/L | 15 pCi/L | Above the health goalThe health goal is zero |
| Ironhighest measured · range ND to 0.66 · sampled 2024 · 2025 report, page 3 | 0.66 ppm | — | 0.3 ppm guideline | Above the guideline2.2x the guideline (taste, odor or stains; not a health limit) |
| Lead90th percentile of homes tested, 0 over the action level · Customer taps · 2025 report, page 2 | 2.78 ppb | 0.2 ppb | 15 ppb (action level) | Above the health goal14x the health goal |
| Radium (combined 226 + 228)highest measured · range 2.4 to 4.1 · 2025 report, page 2 | 4.1 pCi/L | 0 pCi/L | 5 pCi/L | Above the health goalThe health goal is zero |
| Radium-226highest measured · range 2.4 to 4.1 · 2025 report, page 2 | 4.1 pCi/L | 0.05 pCi/L | 5 pCi/L | Above the health goal82x the health goal |
| Bariumhighest measured · range 0.04 to 0.14 · sampled 2024 · 2025 report, page 2 | 0.14 ppm | 2 ppm | 2 ppm | Below the health goal |
| Chloridehighest measured · range 6.85 to 77.2 · sampled 2024 · 2025 report, page 3 | 77.2 ppm | — | 250 ppm guideline | Within the guideline |
| Copper90th percentile of homes tested, 0 over the action level · Customer taps · 2025 report, page 2 | 0.13 ppm | 0.3 ppm | 1.3 ppm (action level) | Below the health goal |
| Disinfection byproducts (TTHM)highest running annual average · range 1.37 to 1.37 · DBPDUAL-03 · 2025 report, page 2 | 1 ppb | None set | 80 ppb | Below the legal limit |
| Manganesehighest measured · range ND to 0.01 · sampled 2024 · 2025 report, page 3 | 0.01 ppm | — | 0.05 ppm guideline | Within the guideline |
| pHhighest measured · range 7.76 to 8.06 · sampled 2024 · 2025 report, page 3 | 8.06 | — | — | Normal range |
| Sulfatehighest measured · range 20.8 to 33.6 · sampled 2024 · 2025 report, page 3 | 33.6 ppm | — | 250 ppm guideline | Within the guideline |
| Total dissolved solidshighest measured · range 324 to 406 · sampled 2024 · 2025 report, page 3 | 406 ppm | — | 500 ppm guideline | Within the guideline |
| Zinchighest measured · range 0.0018 to 0.02 · sampled 2024 · 2025 report, page 3 | 0.02 ppm | — | 5 ppm guideline | Within the guideline |
| Alkalinityhighest measured · range 304 to 342 · sampled 2024 · 2025 report, page 3 | 342 ppm | None set | None | No health limit |
| Calciumhighest measured · range 60.8 to 70.6 · sampled 2024 · 2025 report, page 3 | 70.6 ppm | None set | None | No health limit |
| Hardnesshighest measured · range 16 to 18.3 · sampled 2024 · 2025 report, page 3 | 18.3 gpg (312 ppm) | — | — | Very hard |
| Lithiumhighest measured · range ND to 36.7 · highest of 2 sources · 2025 report, page 3 | 36.7 ppb | None set | None | No health limit |
| Magnesiumhighest measured · range 25.5 to 33.8 · sampled 2024 · 2025 report, page 3 | 33.8 ppm | None set | None | No health limit |
| Nickelhighest measured · range 1.85 to 2.35 · printed as 0.00235 MG/L · sampled 2024 · 2025 report, page 3 | 2.35 ppb | None set | None | No health limit |
| Potassiumhighest measured · range 3.79 to 8.83 · sampled 2024 · 2025 report, page 3 | 8.83 ppm | None set | None | No health limit |
| Sodiumhighest measured · range 25.7 to 53.3 · sampled 2024 · 2025 report, page 3 | 53.3 ppm | None set | None | No health limit |
Utility results describe the whole system, measured where water enters the pipes, not your tap. Your home’s plumbing can add lead or copper.
EPA testing for PFAS and lithium
EPA’s own nationwide testing (UCMR 5) found these in Boone County Pwsd 9’s water between May 2024 and Nov 2024. These are EPA lab results, separate from the district’s report. Anything not listed was not detected.
- Lithium43.9 ppbFound in 10 of 10 samples · highest resultAbove EPA’s health reference level of 10 ppb (a guide, not a legal limit)
Source: EPA UCMR 5 occurrence data. The highest single result is shown; one high sample doesn’t mean every glass is that high.
What you can do
Nothing here is an emergency notice: if the district has a violation, it must tell customers directly. If you’d like to lower these at your tap, these are the treatments that remove them, and the catalog shows the models certified for each. Ranking is by certified removal; commissions never change the order.
Fluoride
Found: Fluoride
What removes it: Reverse osmosis.
Radium and uranium
Found: Gross alpha (radioactivity), Radium (combined 226 + 228), Radium-226
What removes it: Reverse osmosis.
Lead
Found: Lead
What removes it: Certified carbon block or RO.
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