We read 11 results from Northbrook’s 2024 water quality report. No results over a legal limit; 2 above a health goal or guideline.
Serves about 34,407 people · Water system ID IL0312070 · Read the district’s 2024 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 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 |
|---|---|---|---|---|
| Lead90th percentile of homes tested, 0 over the action level · Customer taps · 2024 report, page 9 | 4.5 ppb | 0.2 ppb | 15 ppb (action level) | Above the health goal23x the health goal |
| Radium (combined 226 + 228)single sample · Treated water · 2024 report, page 9 | 0.6 pCi/L | 0 pCi/L | 5 pCi/L | Above the health goalThe health goal is zero |
| Bariumsingle sample · range 0.02 to 0.02 · Treated water · 2024 report, page 9 | 0.02 ppm | 2 ppm | 2 ppm | Below the health goal |
| Chlorinehighest running annual average · range 1 to 1.4 · Distribution system · 2024 report, page 9 | 1.1 ppm | None set | 4 ppm | Below the legal limit |
| Copper90th percentile of homes tested, 0 over the action level · Customer taps · 2024 report, page 9 | 0.17 ppm | 0.3 ppm | 1.3 ppm (action level) | Below the health goal |
| Disinfection byproducts (HAA5)highest running annual average · range 10.3 to 24.9 · Distribution system · 2024 report, page 9 | 20 ppb | None set | 60 ppb | Below the legal limit |
| Disinfection byproducts (TTHM)highest running annual average · range 17.6 to 44.4 · Distribution system · 2024 report, page 9 | 40 ppb | None set | 80 ppb | Below the legal limit |
| Fluorideaverage · range 0.68 to 0.68 · Treated water · 2024 report, page 9 | 0.68 ppm | 1 ppm | 4 ppm | Below the health goal |
| Nitrate (as N)single sample · Treated water · 2024 report, page 9 | 0.32 ppm | 10 ppm | 10 ppm | Below the health goal |
| Seleniumsingle sample · Treated water · 2024 report, page 9 | 1 ppb | 30 ppb | 50 ppb | Below the health goal |
| Sodiumsingle sample · Treated water · 2024 report, page 9 | 11 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.
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: Lead
What removes it: Certified carbon block or RO.
Radium and uranium
Found: Radium (combined 226 + 228)
What removes it: Reverse osmosis.
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