Water Quality Report · Updated May 12, 2026
CAL AMERICAN WATER CO
CAL AMERICAN WATER CO delivers tap water graded D (59/100) by TapWaterSafety.org. The utility serves approximately 66,809 residents in ROSEMEAD, California using surface water (purchased). The most significant water quality concerns are: Haloacetic acids (HAA5) significantly above health guideline; Arsenic* significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline. For questions, the utility can be reached at 626-614-2531.
Is ROSEMEAD tap water safe to drink?
CAL AMERICAN WATER CO delivers tap water that earns a grade of D (59/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including haloacetic acids (haa5) significantly above health guideline.
The utility serves 66,809 residents in ROSEMEAD, drawing from surface water (purchased).
Public testing data identifies 16 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA5), Arsenic*, Haloacetic acids (HAA9), Radon*, Total trihalomethanes (TTHMs), Dibromoacetic acid, Dibromochloromethane, Bromodichloromethane, Chromium (hexavalent), Bromoform, Dichloroacetic acid, Chloroform, Trichloroacetic acid, Uranium*, Nitrate*, Nitrate and nitrite*. 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 ROSEMEAD residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for CAL AMERICAN WATER CO.
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 1.1 ppb, 275x above the EWG health guideline of 0.004 ppb.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 11.1 ppb, 186x above the EWG health guideline of 0.06 ppb.
Contact CAL AMERICAN WATER CO
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Recommended water filters for ROSEMEAD
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 59/100 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 |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Arsenic* Heavy metal |
1.1 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 275× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
11.1 ppb | 0.06 | — | — | — | — | — | 186× over |
| Radon* Radiological |
258.72 pCi/L | 1.5 | — | — | — | — | — | 172× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
22.3 ppb | 0.15 | 80.0 | 100 | — | — | — | 149× over |
| Dibromoacetic acid Disinfection byproduct |
3.01 ppb | 0.03 | — | — | — | — | — | 100× over |
| Dibromochloromethane Disinfection byproduct |
8.25 ppb | 0.1 | — | — | — | — | — | 82× over |
| Bromodichloromethane Disinfection byproduct |
4.13 ppb | 0.06 | — | — | — | — | — | 69× over |
| Chromium (hexavalent) Heavy metal |
0.363 ppb | 0.02 | — | — | — | — | — | 18× over |
| Bromoform Disinfection byproduct |
8.2 ppb | 0.5 | — | — | — | — | — | 16× over |
| Dichloroacetic acid Disinfection byproduct |
2.02 ppb | 0.2 | — | — | — | — | — | 10× over |
| Chloroform Disinfection byproduct |
1.72 ppb | 0.4 | — | — | — | — | — | 4.3× over |
| Trichloroacetic acid Disinfection byproduct |
0.389 ppb | 0.1 | — | — | — | — | — | 3.9× over |
| Uranium* Radiological |
1.09 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 2.5× over |
| Nitrate* Inorganic |
0.173 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 1.2× over |
| Nitrate and nitrite* Inorganic |
0.16 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 1.1× over |
| Bromochloromethane Other |
0.02 ppb | 0.06 | — | — | — | — | — | Below guideline |
| Vanadium Other |
4.09 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
29.3 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Selenium* Heavy metal |
2.65 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Dichloromethane (methylene chloride)* Volatile organic compound |
0.323 ppb | 4.0 | 5.0 | — | — | — | — | Below guideline |
| Molybdenum Other |
2.94 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid* Disinfection byproduct |
1.07 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
1.81 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.149 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.293 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Xylenes (total)* Volatile organic compound |
0.0318 ppb | 1800.0 | 10000.0 | — | — | — | — | Below guideline |
| Dibromomethane* Other |
1.33 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride* Inorganic |
0.631 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
16.2 ppb | — | — | — | — | — | — | Below guideline |
| Nitrite* Inorganic |
0.0128 ppm | — | 1.0 | — | — | — | — | 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.
CAL AMERICAN WATER CO service area
This water system serves 1 community in Ventura County, California. Click any city for its dedicated tap water quality page.
Find the right filter for ROSEMEAD water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.