Water report · not indexed
What is in the water at 90650
3 public water systems serve this ZIP code in the federal records. Everything below comes from EPA monitoring data, and everything missing is named.
GSWC - NORWALK
PWSID CA1910098 · CA · serves 43,176 people
PFAS and lithium
4 compounds detected at or above the reporting limit under EPA’s UCMR 5 monitoring, across 12 samples.
| Compound | Highest detected | Samples | Most recent |
|---|---|---|---|
| lithium | 58 µg/L | 4 | 7/25/2023 |
| PFPeA | 0.015 µg/L | 2 | 3/13/2024 |
| PFHxA | 0.013 µg/L | 2 | 3/13/2024 |
| PFBA | 0.0073 µg/L | 4 | 7/19/2023 |
A detection is a measurement, not a violation and not a health finding. EPA states that UCMR 5 results do not indicate compliance or non-compliance with any limit.
Health-based violations
No open health-based violation on record. This covers MCL, treatment technique and MRDL violations in SDWIS that have not been returned to compliance. It excludes monitoring and reporting violations, which are the large majority nationally, so this is not “no violations”, and SDWIS completeness varies by state.
Hardness
No hardness measurement. Hardness is measured at environmental monitoring stations, and none fell inside this system’s service area. That is a gap in where monitoring happens, not a finding about the water.
NORWALK - CITY, WATER DEPT.
PWSID CA1910191 · CA · serves 20,283 people
PFAS and lithium
6 compounds detected at or above the reporting limit under EPA’s UCMR 5 monitoring, across 31 samples.
| Compound | Highest detected | Samples | Most recent |
|---|---|---|---|
| lithium | 59 µg/L | 16 | 8/26/2024 |
| PFOS | 0.026 µg/L | 4 | 8/26/2024 |
| PFHxS | 0.0076 µg/L | 4 | 8/26/2024 |
| PFBA | 0.0056 µg/L | 2 | 8/26/2024 |
| PFOA | 0.0052 µg/L | 4 | 8/26/2024 |
| PFPeA | 0.0034 µg/L | 1 | 8/26/2024 |
A detection is a measurement, not a violation and not a health finding. EPA states that UCMR 5 results do not indicate compliance or non-compliance with any limit.
Health-based violations
No open health-based violation on record. This covers MCL, treatment technique and MRDL violations in SDWIS that have not been returned to compliance. It excludes monitoring and reporting violations, which are the large majority nationally, so this is not “no violations”, and SDWIS completeness varies by state.
Hardness
No hardness measurement. Hardness is measured at environmental monitoring stations, and none fell inside this system’s service area. That is a gap in where monitoring happens, not a finding about the water.
LIBERTY UTILITIES - BELLFLOWER-NORWALK
PWSID CA1910211 · CA · serves 72,624 people
PFAS and lithium
9 compounds detected at or above the reporting limit under EPA’s UCMR 5 monitoring, across 62 samples.
| Compound | Highest detected | Samples | Most recent |
|---|---|---|---|
| lithium | 89 µg/L | 12 | 8/3/2023 |
| PFOS | 0.059 µg/L | 8 | 8/3/2023 |
| PFPeA | 0.017 µg/L | 6 | 8/3/2023 |
| PFOA | 0.016 µg/L | 6 | 8/3/2023 |
| PFHxS | 0.011 µg/L | 8 | 8/3/2023 |
| PFHxA | 0.01 µg/L | 6 | 8/3/2023 |
| PFBS | 0.0089 µg/L | 6 | 8/3/2023 |
| PFBA | 0.0087 µg/L | 6 | 8/3/2023 |
| PFHpA | 0.0039 µg/L | 4 | 8/3/2023 |
A detection is a measurement, not a violation and not a health finding. EPA states that UCMR 5 results do not indicate compliance or non-compliance with any limit.
Health-based violations
No open health-based violation on record. This covers MCL, treatment technique and MRDL violations in SDWIS that have not been returned to compliance. It excludes monitoring and reporting violations, which are the large majority nationally, so this is not “no violations”, and SDWIS completeness varies by state.
Hardness
No hardness measurement. Hardness is measured at environmental monitoring stations, and none fell inside this system’s service area. That is a gap in where monitoring happens, not a finding about the water.
What this report cannot tell you
Every figure describes water at a sampling point: a treatment plant, an entry point to the distribution system, or a monitoring station. None of it describes water arriving at your tap. Plumbing between the two can add lead and copper, and if your home was built before 1986 a test kit tells you something no federal dataset can.
Sources: EPA UCMR 5 occurrence (final release, frozen July 2026) · EPA SDWIS health-based violations · USGS and state monitoring via the Water Quality Portal · EPA Public Water System Service Area Boundaries v3. Compiled 2026-09-01.