Water Quality Report · Updated May 12, 2026
GSWC - FLORENCE/GRAHAM
GSWC - FLORENCE/GRAHAM delivers tap water graded D (64/100) by TapWaterSafety.org. The utility serves approximately 63,500 residents in ANAHEIM, California using surface water (purchased). The most significant water quality concerns are: Chromium (hexavalent) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Arsenic* significantly above health guideline. For questions, the utility can be reached at 626-250-1517.
Is ANAHEIM tap water safe to drink?
GSWC - FLORENCE/GRAHAM delivers tap water that earns a grade of D (64/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including chromium (hexavalent) significantly above health guideline.
The utility serves 63,500 residents in ANAHEIM, drawing from surface water (purchased).
Public testing data identifies 17 contaminants in this water above EWG's health-based guidelines, including: Chromium (hexavalent), Haloacetic acids (HAA5), Arsenic*, Total trihalomethanes (TTHMs), Haloacetic acids (HAA9), Dibromoacetic acid, Bromodichloromethane, Dibromochloromethane, Nitrate, Uranium, Bromoform, Dichloroacetic acid, Chloroform, Nitrate and nitrite*, Trichloroacetic acid, Radium, combined (-226 and -228)*, Perchlorate. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
Quick actions for ANAHEIM residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for GSWC - FLORENCE/GRAHAM.
Chromium (hexavalent) significantly above health guideline
Moderate concernChromium (hexavalent) detected at 27.8 ppb, 1388x above the EWG health guideline of 0.02 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 36.2 ppb, 362x above the EWG health guideline of 0.1 ppb.
Arsenic* significantly above health guideline
Moderate concernArsenic* detected at 0.16 ppb, 40x above the EWG health guideline of 0.004 ppb.
Contact GSWC - FLORENCE/GRAHAM
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for ANAHEIM
Filters matched to the specific contaminants in this water supply.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Reverse Osmosis
$249-$750Arsenic is most effectively removed by reverse osmosis. Some specialized adsorptive filters also work.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 64/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Chromium (hexavalent) Heavy metal |
27.8 ppb | 0.02 | — | — | — | — | — | 1388× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Arsenic* Heavy metal |
0.16 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 40× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
5.43 ppb | 0.15 | 80.0 | 100 | — | — | — | 36× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
1.7 ppb | 0.06 | — | — | — | — | — | 28× over |
| Dibromoacetic acid Disinfection byproduct |
0.632 ppb | 0.03 | — | — | — | — | — | 21× over |
| Bromodichloromethane Disinfection byproduct |
1.07 ppb | 0.06 | — | — | — | — | — | 18× over |
| Dibromochloromethane Disinfection byproduct |
1.83 ppb | 0.1 | — | — | — | — | — | 18× over |
| Nitrate Inorganic |
1.52 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 11× over |
| Uranium Radiological |
4.2 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 9.8× over |
| Bromoform Disinfection byproduct |
1.89 ppb | 0.5 | — | — | — | — | — | 3.8× over |
| Dichloroacetic acid Disinfection byproduct |
0.509 ppb | 0.2 | — | — | — | — | — | 2.5× over |
| Chloroform Disinfection byproduct |
0.84 ppb | 0.4 | — | — | — | — | — | 2.1× over |
| Nitrate and nitrite* Inorganic |
0.287 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.0× over |
| Trichloroacetic acid Disinfection byproduct |
0.145 ppb | 0.1 | — | — | — | — | — | 1.4× over |
| Radium, combined (-226 and -228)* Radiological |
0.07 pCi/L | 0.05 | 5.0 | — | — | — | — | 1.4× over |
| Perchlorate Disinfection byproduct |
1.18 ppb | 1.0 | — | — | — | — | — | 1.2× over |
| Chlorate Disinfection byproduct |
110.8 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Molybdenum Other |
7.66 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
3.34 ppb | 21.0 | — | — | — | — | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.0467 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Barium Heavy metal |
91.4 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Aluminum* Heavy metal |
77.5 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| 1,2-Dichloroethane Volatile organic compound |
0.0134 ppb | 0.4 | 5.0 | — | — | — | — | Below guideline |
| Manganese Heavy metal |
3.33 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Selenium Heavy metal |
0.9 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Trichloroethylene Volatile organic compound |
0.000953 ppb | 0.4 | 5.0 | 10 | 20 | 1.7 | — | Below guideline |
| Strontium Radiological |
0.795 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0114 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.0227 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Chromium (total) Heavy metal |
22.1 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.426 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
21.5 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
GSWC - FLORENCE/GRAHAM service area
This water system serves 1 community in Los Angeles County, California. Click any city for its dedicated tap water quality page.
Find the right filter for ANAHEIM water
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