ZIP Code 51101
High RiskPFAS above EPA limits detected
3 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.
9
PFAS Detected
3
Above EPA Limits
1
Water System
350%
Highest % of MCL
Compounds Exceeding EPA Limits
PFHxS Exceeds EPA limit
0 ppt MCL: 10 ppt 350% of limit
Detected: 35.00 ppt
PFOA Exceeds EPA limit
0 ppt MCL: 4 ppt 150% of limit
Detected: 6.00 ppt
PFOS Exceeds EPA limit
0 ppt MCL: 4 ppt 108% of limit
Detected: 4.30 ppt
SIOUX CITY WATER SUPPLY
IA9778054 High RiskWater Type
GU
PFAS Detected
9
Above MCL
3
State
Iowa
Data Period
2023–2025
PFAS Test Results
| Compound | Detected | vs. EPA Limit | EPA Limit | Status |
|---|---|---|---|---|
PFHxS Perfluorohexane sulfonic acid | 35.00ppt | 350% of limit
| 10 ppt | ⚠ Exceeds MCL |
PFOA Perfluorooctanoic acid | 6.00ppt | 150% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFOS Perfluorooctane sulfonic acid | 4.30ppt | 108% of limit
| 4 ppt | ⚠ Exceeds MCL |
PFHxA Perfluorohexanoic acid | 33.00ppt | No federal limit | — | Unregulated |
PFPeA Perfluoropentanoic acid | 22.00ppt | No federal limit | — | Unregulated |
PFBS Perfluorobutane sulfonic acid | 21.00ppt | No federal limit | — | Unregulated |
PFPeS | 14.00ppt | No federal limit | — | Unregulated |
PFBA Perfluorobutanoic acid | 9.20ppt | No federal limit | — | Unregulated |
Show 1 more compound detected at low levels
| PFHpAPerfluoroheptanoic acid | 4.80 ppt | No federal limit |
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.