Tap Water Quality Report
Tap water quality in RIALTO, California
Tap water in RIALTO, California receives a grade of F (58/100) from TapWaterSafety.org. It's served by 2 public water systems, primarily RIALTO, CITY OF. The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Arsenic significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in RIALTO's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utilities serving RIALTO.
PFAS contamination
Severe concernPerfluorooctanoic acid (PFOA) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Perfluorohexane sulfonate (PFHXS) significantly above health guideline
Moderate concernPerfluorohexane sulfonate (PFHXS) detected at 0.919 ppt, 919x above the EWG health guideline of 0.001 ppt.
Arsenic significantly above health guideline
Moderate concernArsenic detected at 2.52 ppb, 630x above the EWG health guideline of 0.004 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.
EPA compliance record
Official U.S. EPA records for RIALTO, CITY OF (system ID CA3610038) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Water systems serving RIALTO
RIALTO is served by 2 public water systems. Click any utility to see its complete grade card and treatment plant contact info.
RIALTO, CITY OF
- PFAS contamination
- Perfluorohexane sulfonate (PFHXS) significantly above health guideline
- Arsenic significantly above health guideline
WEST VALLEY WATER DISTRICT
- PFAS contamination
- Perfluorohexane sulfonate (PFHXS) significantly above health guideline
- Arsenic significantly above health guideline
Recommended filters for RIALTO
Filters matched to the specific contaminants in RIALTO's water supply.
Filter certified for PFOA/PFOS (NSF/ANSI 53 or 58)
$180-$750Reverse osmosis and some carbon block filters reduce PFAS. Look for certification to NSF/ANSI 53 or 58 for PFOA/PFOS.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in RIALTO's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. 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 |
|---|---|---|---|---|---|---|---|---|
| Perfluorohexane sulfonate (PFHXS) PFAS |
1.35 ppt | 0.001 | 10.0 | — | — | — | — | 1345× over |
| Arsenic Heavy metal |
2.64 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 659× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
18.1 ppb | 0.06 | — | — | — | — | — | 301× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
16.0 ppb | 0.15 | 80.0 | 100 | — | — | — | 107× over |
| Bromodichloromethane Disinfection byproduct |
4.47 ppb | 0.06 | — | — | — | — | — | 75× over |
| Chromium (hexavalent) Heavy metal |
1.2 ppb | 0.02 | — | — | — | — | — | 60× over |
| Dibromochloromethane Disinfection byproduct |
4.24 ppb | 0.1 | — | — | — | — | — | 42× over |
| Dibromoacetic acid Disinfection byproduct |
1.02 ppb | 0.03 | — | — | — | — | — | 34× over |
| Nitrate Inorganic |
3.53 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 25× over |
| Nitrate and nitrite Inorganic |
2.94 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 21× over |
| Perfluorooctanoic acid (PFOA) PFAS |
1.87 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 21× over |
| Radium, combined (-226 and -228) Radiological |
0.84 pCi/L | 0.05 | 5.0 | — | — | — | — | 17× over |
| Chloroform Disinfection byproduct |
5.97 ppb | 0.4 | — | — | — | — | — | 15× over |
| Trichloroacetic acid Disinfection byproduct |
1.42 ppb | 0.1 | — | — | — | — | — | 14× over |
| Dichloroacetic acid Disinfection byproduct |
1.83 ppb | 0.2 | — | — | — | — | — | 9.1× over |
| Uranium Radiological |
2.9 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 6.7× over |
| Tetrachloroethylene (perchloroethylene) Volatile organic compound |
0.3 ppb | 0.06 | 5.0 | — | — | — | — | 5.0× over |
| Trichloroethylene Volatile organic compound |
1.97 ppb | 0.4 | 5.0 | 10 | 20 | 1.7 | — | 4.9× over |
| Bromoform Disinfection byproduct |
1.37 ppb | 0.5 | — | — | — | — | — | 2.7× over |
| Chlorate Disinfection byproduct |
80.5 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Perchlorate Disinfection byproduct |
0.226 ppb | 1.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
4.23 ppb | 21.0 | — | — | — | — | — | Below guideline |
| 4,8-dioxa-3H-perfluorononanoic acid (ADONA) PFAS |
0.116 ppt | 1.0 | — | — | — | — | — | Below guideline |
| Molybdenum Other |
2.85 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Bromochloromethane Other |
0.00263 ppb | 0.06 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
3.83 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.01 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| MTBE Volatile organic compound |
0.206 ppb | 13.0 | — | — | — | — | — | Below guideline |
| Aluminum Heavy metal |
1.84 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
2.92 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
1.68 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
1.07 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
1.59 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0191 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
0.589 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Cobalt Other |
0.0273 ppb | 70.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.332 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| 1,1-Dichloroethane Volatile organic compound |
0.000534 ppb | 3.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.289 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| 1-Butanol Other |
0.111 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, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from RIALTO, CITY OF.