ZIP Code 91723
High RiskPFAS above EPA limits detected
4 compounds exceed EPA Maximum Contaminant Levels in water serving this ZIP code. Standard pitcher filters like Brita do not remove PFAS. See filter recommendations below.
17
PFAS Detected
4
Above EPA Limits
5
Water Systems
193%
Highest % of MCL
Compounds Exceeding EPA Limits
PFOA Exceeds EPA limit
0 ppt MCL: 4 ppt 193% of limit
Detected: 7.70 ppt
PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 145% of limit
Detected: 5.80 ppt
AZUSA LIGHT AND WATER
CA1910007 High RiskWater Type
Groundwater
PFAS Detected
3
Above MCL
2
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOA Perfluorooctanoic acid | 7.70ppt | 193% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOS Perfluorooctane sulfonic acid | 5.80ppt | 145% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxA Perfluorohexanoic acid | 3.50ppt | No federal limit | — | Unregulated |
COVINA-CITY, WATER DEPT.
CA1910127 Low LevelWater Type
Surface Water
PFAS Detected
1
Above MCL
0
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
lithium | 47000.00ppt | No federal limit | — | Unregulated |
VALENCIA HEIGHTS WATER CO.
CA1910163 High RiskWater Type
Surface Water
PFAS Detected
7
Above MCL
2
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFOA Perfluorooctanoic acid | 5.70ppt | 143% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOS Perfluorooctane sulfonic acid | 4.40ppt | 110% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxS Perfluorohexane sulfonic acid | 3.60ppt | 36% of limit
| 10 ppt | Below limit |
lithium | 9800.00ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 4.40ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 4.30ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 4.00ppt | No federal limit | — | Unregulated |
SUBURBAN WATER SYSTEMS-SAN JOSE
CA1910205 ModerateWater Type
Surface Water
PFAS Detected
5
Above MCL
0
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
lithium | 54000.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 6.20ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 3.60ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 3.50ppt | No federal limit | — | Unregulated |
PFHxA Perfluorohexanoic acid | 3.30ppt | No federal limit | — | Unregulated |
WALNUT VALLEY WATER DISTRICT
CA1910234 Low LevelWater Type
Surface Water
PFAS Detected
1
Above MCL
0
State
California
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
lithium | 50100.00ppt | No federal limit | — | Unregulated |
Note: ZIP code 91723 is served by 5 separate water utilities.
Results above show data for each system independently.
Data source: EPA Unregulated Contaminant Monitoring Rule, 5th cycle (UCMR 5) — January 2026 release.
UCMR 5 tested ~10,000 public water systems serving more than 25 people between 2023-2025 for 29 PFAS compounds.
Detection values represent the highest single-sample result measured at entry points to the distribution system.