Water report · not indexed
What is in the water at 57049
4 public water systems serve this ZIP code in the federal records. Everything below comes from EPA monitoring data, and everything missing is named.
CLAY RWS/SOUTH UNION
PWSID SD4602185 · SD · serves 1,447 people
PFAS and lithium
Not sampled for PFAS. EPA’s UCMR 5 monitoring covered every system serving more than 3,300 people and only a sample of smaller ones. This system was not in it, so there is no result to show, which is not the same as a result showing nothing.
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.
SIOUX CITY WATER SUPPLY
PWSID IA9778054 · IA · serves 85,791 people
PFAS and lithium
10 compounds detected at or above the reporting limit under EPA’s UCMR 5 monitoring, across 39 samples.
| Compound | Highest detected | Samples | Most recent |
|---|---|---|---|
| lithium | 240 µg/L | 8 | 7/15/2024 |
| PFHxS | 0.035 µg/L | 4 | 7/15/2024 |
| PFHxA | 0.033 µg/L | 4 | 7/15/2024 |
| PFPeA | 0.022 µg/L | 4 | 7/15/2024 |
| PFBS | 0.021 µg/L | 4 | 7/15/2024 |
| PFPeS | 0.014 µg/L | 4 | 7/15/2024 |
| PFBA | 0.0092 µg/L | 4 | 7/15/2024 |
| PFOA | 0.006 µg/L | 2 | 4/16/2024 |
| PFHpA | 0.0048 µg/L | 3 | 7/15/2024 |
| PFOS | 0.0043 µg/L | 2 | 4/16/2024 |
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.
NORTH SIOUX CITY
PWSID SD4600226 · SD · serves 3,042 people
PFAS and lithium
Not sampled for PFAS. EPA’s UCMR 5 monitoring covered every system serving more than 3,300 people and only a sample of smaller ones. This system was not in it, so there is no result to show, which is not the same as a result showing nothing.
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.
DAKOTA DUNES CID
PWSID SD4602093 · SD · serves 3,700 people
PFAS and lithium
Not sampled for PFAS. EPA’s UCMR 5 monitoring covered every system serving more than 3,300 people and only a sample of smaller ones. This system was not in it, so there is no result to show, which is not the same as a result showing nothing.
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.