Sioux City Water Supply

ZipCheckup's reading of EPA SDWIS for Sioux City Water Supply (IA9778054): PFAS sampling above the current EPA limit (UCMR5). A total of 2 EPA violations spanning the past five monitoring years sit on Sioux City Water Supply's record - every finding has been officially cleared, and the supplier now holds current compliance status for its service population of approximately 85,791 people, with no outstanding enforcement of any kind.

Data: EPA SDWIS

System Overview

Sioux City Water Supply (EPA ID: IA9778054) is a community water system in Iowa that serves approximately 85,791 people from surface water sources.

This system provides water to 9 ZIP codes across 3 communities.

ZIP-Area Home Safety Context: D (49/100)

This is the average Home Safety Score for 6 of 9 service-area ZIP codes with all required score domains observed. It is not a grade for the water utility.

Model 4.0.0 uses SDWIS identity plus accepted ECHO SDWA lifecycle-based water compliance, the UCMR 5 PFAS MCL screen, EPA radon zone, and annual EPA AirData AQI across three equally weighted domains. Missing required evidence suppresses the score.

Violation History

Status breakdown for accepted records with record years 2021-2026: 2 resolved, 0 archived, 0 addressed, and 0 unaddressed. Under this source contract, current noncompliance is the sum of addressed and unaddressed records. Archived and resolved records are excluded from current noncompliance.

Recent Violations

Contaminants Detected

The following contaminants have been flagged in EPA records for this water system:

Lead & Copper

EPA Lead and Copper Rule evidence attributed directly to this water system:

No copper action-level exceedance record appears for this PWSID in the accepted LCR snapshot. This does not establish a clean copper measurement.

Radon Risk in Service Area

Dominant radon zone for ZIP codes served by this system: Zone 1 (High Risk)

The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.

ZIP Codes Served

Coverage: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by IA or modeled from parcel and building-footprint data.

• 51030 - Lawton
• 51054 - Sergeant Bluff
• 51101 - Sioux City
• 51103 - Sioux City
• 51104 - Sioux City
• 51105 - Sioux City
• 51106 - Sioux City
• 51108 - Sioux City
• 51109 - Sioux City

Data Sources

This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Sioux City Water Supply (IA9778054) on EPA.gov.

Frequently Asked Questions

Is Sioux City Water Supply water safe to drink?

The accepted 2026Q2 ECHO snapshot shows no current noncompliance for Sioux City Water Supply; its 2 accepted 2021-2026 records are resolved or archived. Historical compliance status does not establish conditions at a specific tap.

How many people does Sioux City Water Supply serve?

Sioux City Water Supply serves approximately 85,791 people across 9 ZIP codes in Iowa.

Where does Sioux City Water Supply get its water?

The primary water source is surface water.

@misc{zipcheckup-water-system-ia9778054,
  author = {{ZipCheckup}},
  title  = {{Sioux City Water Supply (IA): 2 EPA Violations}},
  year   = {n.d.},
  url    = {https://zipcheckup.com/water-system/ia9778054/}
}