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Tap water quality report

Hawthorne, CA

EPA monitoring detected 19 contaminants across the 2 water suppliers serving Hawthorne. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

2
water suppliers
322,458
people served
19
contaminants found
California rankings Lead in California PFAS in California

What was found in Hawthorne'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
959 µg/L 24%
of the EPA limit 4000 µg/L
 2/2 SYR4
TTHM
121.83 µg/L 152%
of the EPA limit, in the worst sample — 80 µg/L
 2/2 SYR4
Barium
120 µg/L 6%
of the EPA limit 2000 µg/L
 1/2 SYR4
Lithium
51.3 µg/L
No EPA limit set
 2/2 UCMR-5
Dibromochloromethane
45 µg/L
No EPA limit set
 2/2 SYR4
Chloroform
40 µg/L
No EPA limit set
 2/2 SYR4
Total Haloacetic Acids (HAA5)
37 µg/L 62%
of the EPA limit 60 µg/L
 2/2 SYR4
Bromoform
36.5 µg/L
No EPA limit set
 2/2 SYR4
Bromodichloromethane
29 µg/L
No EPA limit set
 2/2 SYR4
Copper
20.56 µg/L 1.6%
of the EPA limit 1300 µg/L
 1/2 SYR4
Dichloroacetic Acid
18 µg/L
No EPA limit set
 2/2 SYR4
Trichloroacetic Acid
17 µg/L
No EPA limit set
 2/2 SYR4
Dibromoacetic Acid
12 µg/L
No EPA limit set
 2/2 SYR4
Monochloroacetic Acid
6.8 µg/L
No EPA limit set
 2/2 SYR4
Combined Uranium
5.96 µg/L 20%
of the EPA limit 30 µg/L
 1/2 SYR4
Selenium
5.3 µg/L 11%
of the EPA limit 50 µg/L
 1/2 SYR4
Monobromoacetic Acid
3.1 µg/L
No EPA limit set
 2/2 SYR4
Arsenic
3 µg/L 30%
of the EPA limit 10 µg/L
 1/2 SYR4
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 2/2 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 Hawthorne

SupplierPopulation served
GSWC - SOUTHWEST 277,740
HAWTHORNE-CITY WATER DEPT. 44,718

Frequently asked questions about Hawthorne tap water

Is Hawthorne tap water safe to drink?

EPA testing detected 19 contaminants in the water serving Hawthorne. 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 Hawthorne?

2 public water suppliers report drinking-water monitoring for Hawthorne, California to the EPA. Each is listed above with its population served.

What contaminants are in Hawthorne's water?

The contaminants EPA monitoring detected in Hawthorne include Fluoride, TTHM, Barium, Lithium, Dibromochloromethane. 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.