We read 24 results from Black Oak Water & Sewer Co’s 2025 water quality report. No results over a legal limit; 4 above a health goal or guideline.
Serves about 477 people · Water system ID MO5036267 · 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 |
|---|---|---|---|---|
| Gross alpha (radioactivity)highest measured · range 10 to 13.2 · sampled 2023 · 2025 report, page 2 | 13.2 pCi/L | 0 pCi/L | 15 pCi/L | Above the health goalThe health goal is zero |
| Radium (combined 226 + 228)highest measured · range 2.4 to 2.5 · sampled 2023 · 2025 report, page 2 | 2.5 pCi/L | 0 pCi/L | 5 pCi/L | Above the health goalThe health goal is zero |
| Radium-226highest measured · range 2.4 to 2.5 · sampled 2023 · 2025 report, page 2 | 2.5 pCi/L | 0.05 pCi/L | 5 pCi/L | Above the health goal50x the health goal |
| Uraniumhighest measured · range 1.9 to 2.11 · sampled 2023 · 2025 report, page 2 | 2.11 ppb | 0.6 ppb | 30 ppb | Above the health goal3.5x the health goal |
| Aluminumhighest measured · range 0.02 to 0.02 · 2025 report, page 3 | 0.02 ppm | — | 0.2 ppm guideline | Within the guideline |
| Bariumhighest measured · range 0.02 to 0.02 · 2025 report, page 2 | 0.02 ppm | 2 ppm | 2 ppm | Below the health goal |
| Chloridehighest measured · range 5.64 to 5.64 · 2025 report, page 3 | 5.64 ppm | — | 250 ppm guideline | Within the guideline |
| Copper90th percentile of homes tested, 0 over the action level · Customer taps · 2025 report, page 2 | 0.08 ppm | 0.3 ppm | 1.3 ppm (action level) | Below the health goal |
| Fluoridehighest measured · range 0.16 to 0.16 · 2025 report, page 2 | 0.16 ppm | 1 ppm | 4 ppm | Below the health goal |
| Ironhighest measured · range 0.17 to 0.17 · 2025 report, page 3 | 0.17 ppm | — | 0.3 ppm guideline | Within the guideline |
| Lead90th percentile of homes tested, 0 over the action level · Customer taps · 2025 report, page 2 | Not detected | 0.2 ppb | 15 ppb (action level) | Not detected |
| Manganesehighest measured · range 0.0067 to 0.0067 · 2025 report, page 3 | 0.0067 ppm | — | 0.05 ppm guideline | Within the guideline |
| Nitrate (as N)highest measured · range 0.02 to 0.02 · 2025 report, page 2 | 0.02 ppm | 10 ppm | 10 ppm | Below the health goal |
| pHhighest measured · range 7.62 to 7.62 · 2025 report, page 3 | 7.62 | — | — | Normal range |
| Sulfatehighest measured · range 20.9 to 20.9 · 2025 report, page 3 | 20.9 ppm | — | 250 ppm guideline | Within the guideline |
| Total dissolved solidshighest measured · range 308 to 308 · 2025 report, page 3 | 308 ppm | — | 500 ppm guideline | Within the guideline |
| Zinchighest measured · range 0.02 to 0.02 · 2025 report, page 3 | 0.02 ppm | — | 5 ppm guideline | Within the guideline |
| Alkalinityhighest measured · range 400 to 400 · 2025 report, page 3 | 400 ppm | None set | None | No health limit |
| Calciumhighest measured · range 64.5 to 64.5 · 2025 report, page 3 | 64.5 ppm | None set | None | No health limit |
| Hardnesshighest measured · range 18.8 to 18.8 · 2025 report, page 3 | 18.8 gpg (322 ppm) | — | — | Very hard |
| Magnesiumhighest measured · range 39.1 to 39.1 · 2025 report, page 3 | 39.1 ppm | None set | None | No health limit |
| Nickelhighest measured · range 5.78 to 5.78 · printed as 0.00578 MG/L · 2025 report, page 3 | 5.78 ppb | None set | None | No health limit |
| Potassiumhighest measured · range 1.5 to 1.5 · 2025 report, page 3 | 1.5 ppm | None set | None | No health limit |
| Sodiumhighest measured · range 5.42 to 5.42 · 2025 report, page 3 | 5.42 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. 1 number we weren’t sure about is held back until a person checks.
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.
Radium and uranium
Found: Gross alpha (radioactivity), Radium (combined 226 + 228), Radium-226, Uranium
What removes it: Reverse osmosis.
More districts: Missouri water quality · All states · Something look wrong? Tell us