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Tap water quality report

Signal Hill, CA

EPA monitoring detected 20 contaminants across the 1 water supplier serving Signal Hill. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

1
water supplier
11,848
people served
20
contaminants found
California rankings Lead in California PFAS in California

What was found in Signal Hill's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Fluoride
573 µg/L 14%
of the EPA limit 4000 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Barium
148.5 µg/L 7.4%
of the EPA limit 2000 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Lithium
58 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2024
1/1 UCMR-5
TTHM
32.725 µg/L 41%
of the EPA limit 80 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Total Haloacetic Acids (HAA5)
20.65 µg/L 34%
of the EPA limit 60 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Chloroform
14 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Benzene
13.15 µg/L 263%
of the EPA limit, at the 95th percentile of samples — 5 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Arsenic
13 µg/L 130%
of the EPA limit, at the 95th percentile of samples — 10 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Monochloroacetic Acid
12.14 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Bromodichloromethane
10 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Dibromochloromethane
9.3675 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Dichloroacetic Acid
9.095 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Trichloroacetic Acid
6.268 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Dibromoacetic Acid
5.51 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Bromoform
3.945 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Monobromoacetic Acid
1.7 µg/L
No EPA limit set
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Ethylbenzene
0.6000 µg/L 0.1%
of the EPA limit 700 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Xylenes, Total
0.5200 µg/L 0%
of the EPA limit 10000 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Nitrite
0.2200 µg/L 0%
of the EPA limit 1000 µg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2019
1/1 SYR4
Lead
0.0029 mg/L 19%
of the EPA limit 0.0150 mg/L
Main supplier: SIGNAL HILL - CITY, WATER DEPT. · 11,848 people · 2026
1/1 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 95th percentile of the system's samples — 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 Signal Hill

SupplierPopulation served
SIGNAL HILL - CITY, WATER DEPT. 11,848

Frequently asked questions about Signal Hill tap water

Is Signal Hill tap water safe to drink?

EPA testing detected 20 contaminants in the water serving Signal Hill. 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 Signal Hill?

1 public water supplier report drinking-water monitoring for Signal Hill, California to the EPA. Each is listed above with its population served.

What contaminants are in Signal Hill's water?

The contaminants EPA monitoring detected in Signal Hill include Fluoride, Barium, Lithium, TTHM, Total Haloacetic Acids (HAA5). The full list, with the level at the main supplier 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.