We read 14 results from Grayslake’s 2025 water quality report. No results over a legal limit; 4 above a health goal or guideline.
Serves about 21,248 people · Water system ID IL0970250 · Read the district’s 2025 report (opens in a new tab)
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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 |
|---|---|---|---|---|
| Bromatehighest running annual average · range ND to 6.4 · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 5 ppb | 0.1 ppb | 10 ppb | Above the health goal50x the health goal |
| PFOA (a PFAS)highest measured · range 1.9 to 2.5 · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 5 | 2.5 ppt | 0.007 ppt | 4 ppt from 2029 | Above the health goal357x the health goal |
| PFOS (a PFAS)highest measured · range ND to 2.4 · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 5 | 2.4 ppt | 1 ppt | 4 ppt from 2029 | Above the health goal2.4x the health goal |
| Radium (combined 226 + 228)single sample · sampled 2021 · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 0.94 pCi/L | 0 pCi/L | 5 pCi/L | Above the health goalThe health goal is zero |
| Bariumsingle sample · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 0.02 ppm | 2 ppm | 2 ppm | Below the health goal |
| Chlorinehighest running annual average · range 0.79 to 1.3 · Distribution system · 2025 report, page 3 | 1 ppm | None set | 4 ppm | Below the legal limit |
| Chromium (total)single sample · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 1 ppb | None set | 100 ppb | Below the legal limit |
| Disinfection byproducts (HAA5)highest running annual average · range ND to 13.8 · Distribution system · 2025 report, page 3 | 9 ppb | None set | 60 ppb | Below the legal limit |
| Disinfection byproducts (TTHM)highest running annual average · range 13.9 to 64.9 · Distribution system · 2025 report, page 3 | 41 ppb | None set | 80 ppb | Below the legal limit |
| Fluoridehighest measured · range 0.48 to 0.7 · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 0.6 ppm | 1 ppm | 4 ppm | Below the health goal |
| Nitrate (as N)single sample · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 0.4 ppm | 10 ppm | 10 ppm | Below the health goal |
| Turbidity (cloudiness)highest measured · range 0.01 to 0.05 · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 0.05 NTU | None set | 1 NTU | Below the legal limit |
| PFBA (a PFAS)highest measured · range ND to 2.1 · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 5 | 2.1 ppt | None set | None | No health limit |
| Sodiumsingle sample · Treated water (CLCJAWA, Lake Michigan) · 2025 report, page 3 | 10 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. 2 numbers we weren’t sure about are 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.
PFAS ("forever chemicals")
Found: PFOA (a PFAS), PFOS (a PFAS)
What removes it: Reverse osmosis.
Radium and uranium
Found: Radium (combined 226 + 228)
What removes it: Reverse osmosis.
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