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Tap water quality report

Northbrook, IL

EPA monitoring detected 23 contaminants across the 6 water suppliers serving Northbrook. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

6
water suppliers
43,381
people served
23
contaminants found
Illinois rankings Lead in Illinois PFAS in Illinois

What was found in Northbrook's water

The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Fluoride
1000 µg/L 25%
of the EPA limit 4000 µg/L
 2/6 SYR4
Copper
822 µg/L 63%
of the EPA limit 1300 µg/L
 3/6 SYR4
Nitrate
432 µg/L 4.3%
of the EPA limit 10000 µg/L
 1/6 SYR4
Nitrate-Nitrite
407 µg/L 4.1%
of the EPA limit 10000 µg/L
 1/6 SYR4
TTHM
58.3 µg/L 73%
of the EPA limit 80 µg/L
 4/6 SYR4
Chloroform
39.5 µg/L
No EPA limit set
 4/6 SYR4
Total Haloacetic Acids (HAA5)
25.2 µg/L 42%
of the EPA limit 60 µg/L
 4/6 SYR4
Barium
22.3 µg/L 1.1%
of the EPA limit 2000 µg/L
 2/6 SYR4
Lead
19.1 µg/L 127%
of the EPA limit, in the worst sample — 15 µg/L
 3/6 SYR4
Dichloroacetic Acid
13.7 µg/L
No EPA limit set
 4/6 SYR4
Bromodichloromethane
13.4 µg/L
No EPA limit set
 3/6 SYR4
Trichloroacetic Acid
10.5 µg/L
No EPA limit set
 4/6 SYR4
Dibromochloromethane
7.27 µg/L
No EPA limit set
 3/6 SYR4
Monobromoacetic Acid
6.21 µg/L
No EPA limit set
 1/6 SYR4
Arsenic
2.87 µg/L 29%
of the EPA limit 10 µg/L
 2/6 SYR4
Monochloroacetic Acid
2.42 µg/L
No EPA limit set
 1/6 SYR4
Bromoform
2.29 µg/L
No EPA limit set
 2/6 SYR4
Combined Radium (-226 And -228)
2.18 pCi/L 44%
of the EPA limit 5 pCi/L
 1/6 SYR4
Selenium
2 µg/L 4%
of the EPA limit 50 µg/L
 1/6 SYR4
Dibromoacetic Acid
1.98 µg/L
No EPA limit set
 3/6 SYR4
P-Dichlorobenzene
0.8760 µg/L 1.2%
of the EPA limit 75 µg/L
 1/6 SYR4
Heptachlor
0.0540 µg/L 13%
of the EPA limit 0.4000 µg/L
 1/6 SYR4
Lead
0.0110 mg/L 73%
of the EPA limit 0.0150 mg/L
 6/6 LCR
Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Northbrook

SupplierPopulation served
NORTHBROOK 34,407
OASIS MHP 3,000
MISSION BROOK SD 2,852
SUNSET MHP 1,400
HARBOR POINT ESTATES MHP 1,064
CAMBRIDGE COURTS MHP 658

Frequently asked questions about Northbrook tap water

Is Northbrook tap water safe to drink?

EPA testing detected 23 contaminants in the water serving Northbrook. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Northbrook?

6 public water suppliers report drinking-water monitoring for Northbrook, Illinois to the EPA. Each is listed above with its population served.

What contaminants are in Northbrook's water?

The contaminants EPA monitoring detected in Northbrook include Fluoride, Copper, Nitrate, Nitrate-Nitrite, TTHM. The full list, with the highest level found and the data source, is in the table above.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.