We read 12 results from Troy’s 2024 water quality report. No results over a legal limit; 3 above a health goal or guideline.
Serves about 16,962 people · Water system ID IL1191000 · Read the district’s 2024 report (opens in a new tab)
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Results from the 2024 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 |
|---|---|---|---|---|
| Copper90th percentile of homes tested, 0 over the action level · 2024 report, page 6 | 0.87 ppm | 0.3 ppm | 1.3 ppm (action level) | Above the health goal2.9x the health goal |
| Gross alpha (radioactivity)as reported · sampled 2020 · 2024 report, page 6 | 3.52 pCi/L | 0 pCi/L | 15 pCi/L | Above the health goalThe health goal is zero |
| Lead90th percentile of homes tested, 0 over the action level · 2024 report, page 6 | 2.3 ppb | 0.2 ppb | 15 ppb (action level) | Above the health goal11x the health goal |
| Bariumas reported · sampled 2023 · 2024 report, page 5 | 0.13 ppm | 2 ppm | 2 ppm | Below the health goal |
| Chlorineaverage · range 1 to 1.5 · 2024 report, page 5 | 1.2 ppm | None set | 4 ppm | Below the legal limit |
| Disinfection byproducts (HAA5)highest running annual average · range 9.9 to 10.3 · 2024 report, page 5 | 10.3 ppb | None set | 60 ppb | Below the legal limit |
| Disinfection byproducts (TTHM)highest running annual average · range 37.6 to 45.9 · 2024 report, page 5 | 46 ppb | None set | 80 ppb | Below the legal limit |
| Fluorideas reported · sampled 2023 · 2024 report, page 5 | 0.62 ppm | 1 ppm | 4 ppm | Below the health goal |
| Nitrate (as N)as reported · range 2.24 to 2.68 · 2024 report, page 5 | 2 ppm | 10 ppm | 10 ppm | Below the health goal |
| Seleniumas reported · sampled 2023 · 2024 report, page 6 | 3.3 ppb | 30 ppb | 50 ppb | Below the health goal |
| PFBS (a PFAS)as reported · printed as .0039 ppb · 2024 report, page 7 | 3.9 ppt | None set | None | No health limit |
| Sodiumas reported · sampled 2023 · 2024 report, page 6 | 36.3 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. 1 number we weren’t sure about is held back until a person checks.
EPA testing for PFAS and lithium
EPA’s own nationwide testing (UCMR 5) found these in Troy’s water between Sep 2024 and Mar 2025. These are EPA lab results, separate from the district’s report. Anything not listed was not detected.
- PFBS3.9 pptFound in 1 of 2 samples · highest resultNo federal limit in force for this one
- Lithium10.9 ppbFound in 2 of 2 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.
Lead
Found: Copper, Lead
What removes it: Reverse osmosis or Certified carbon block or RO.
Radium and uranium
Found: Gross alpha (radioactivity)
What removes it: Reverse osmosis.
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