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WaterSafeCheck

ZIP Code 51102 Water Quality Report

Sioux City, IA · Woodbury County County

Safety Score
B

Water Safety Grade

Good — Minor issues on record

Health Violations

0

Total Violations

1

Lead Risk

N/A

Contaminants

0

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Active Water Quality Issues Detected

EPA records show 0 unresolved violation. Contact Sioux City Water Supply for current status.

About Tap Water in ZIP Code 51102

Tap water in ZIP code 51102 (Sioux City, IA) meets all federal safety standards and earns a solid B grade (score: 70/100). Served by Sioux City Water Supply, the water system has maintained general compliance with EPA Safe Drinking Water Act regulations, with only minor issues on record.

Water System

Sioux City Water Supply

EPA ID: IA9778054

Water Source

Surface Water

Population Served

85,791 residents

County

Woodbury County County, Iowa

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Lead Levels in ZIP 51102

EPA action level: 15 ppb | Public health goal: 0 ppb

Lead Level: 2.0 ppb — Very Low

The 90th percentile lead level in 51102 is 2.0 ppb, well below the EPA action level of 15 ppb. While this is a reassuring result, the EPA's public health goal for lead is actually zero — no amount of lead is considered completely safe, particularly for children under 6 and pregnant women. Running your tap for 30 seconds before use and using a certified NSF/ANSI 53 filter adds an extra layer of protection.
Lead Level (90th percentile)
2.00 ppb (0.002 mg/L)
Lead Exposure Risk Rating
Unknown
Note: Lead levels above are the 90th percentile from EPA monitoring — meaning 90% of samples were at or below this level. Even "undetected" tap water lead doesn't account for lead leaching from home plumbing. If your home was built before 1986, individual tap testing is recommended.
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Violation History

Past 5 years — EPA SDWIS data

Sioux City Water Supply has recorded 1 violation, but none are health-based. Administrative or reporting violations don't directly indicate unsafe water, but they do signal gaps in documentation or monitoring procedures.

Total Violations (5 yr)
1
Health-Based Violations
0
Unresolved Violations
0
Boil Water Advisories
0
Compliance Risk
High

Regulatory compliance risk is rated High. Sioux City Water Supply has a pattern of compliance issues that goes beyond isolated incidents. Residents should stay informed via their utility's Consumer Confidence Report.

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Contaminants Detected

Contaminants with health-based violations on record

No health-based contaminant violations are on record for ZIP code 51102. This means EPA monitoring has not found levels of regulated contaminants exceeding the Maximum Contaminant Levels (MCLs) set under the Safe Drinking Water Act — a positive indicator of water quality compliance.

⚖ Enforcement Actions

4 enforcement actions have been issued against Sioux City Water Supply — a high number that reflects sustained compliance struggles. Enforcement actions escalate from administrative orders to financial penalties when utilities repeatedly fail to meet safe drinking water standards.
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Water Source & Environmental Factors

Surface Water

This system draws water from lakes, rivers, or reservoirs. Surface water is treated to remove sediment, microorganisms, and chemical contaminants before reaching taps.

Water Source Type
Surface Water
CCR Source Classification
Ground Water Under Influence
EPA Radon Zone

Highest potential

Zone 1

EPA Radon Zone 1 — highest potential for radon in indoor air. Homeowners should test their home for radon and consider mitigation if levels exceed 4 pCi/L.

🛡 What Should You Do? — ZIP 51102 Recommendations

  • ✓ Run cold water for 30 seconds each morning before use — especially if pipes are old
  • ✓ Request your annual Consumer Confidence Report from Sioux City Water Supply
  • ✓ If your home was built before 1986, consider testing your own tap for lead
  • ✓ Use a pitcher filter (NSF/ANSI 42 certified) for improved taste

Frequently Asked Questions — ZIP 51102 Water Quality

Is tap water safe to drink in ZIP code 51102?+
Yes — tap water in 51102 (Sioux City, IA) currently meets all federal EPA standards with a water safety grade of B. No health-based violations are on record in the past 5 years. You can drink your tap water with confidence, though running the tap for 30 seconds in the morning is always a good practice.
What is the lead level in 51102 tap water?+
The 90th percentile lead level in 51102 is 2.0 ppb (parts per billion). The EPA action level is 15 ppb. This is a low level, well below the EPA action level of 15 ppb.
Who provides tap water to 51102?+
Tap water in ZIP code 51102 is provided by Sioux City Water Supply (EPA ID: IA9778054). This system serves approximately 85,791 residents. You can contact them directly for Consumer Confidence Reports, current advisories, and billing information.
What is the water source for 51102?+
ZIP code 51102 is served by surface water. Surface water systems draw from rivers, lakes, or reservoirs and must meet strict EPA treatment requirements including filtration and disinfection.
Does 51102 have any active water quality violations?+
No active violations are on record for ZIP code 51102. EPA data shows this water system is currently in compliance with Safe Drinking Water Act standards.
How do I get a copy of my water quality report for 51102?+
Your water utility — Sioux City Water Supply — is required by law to send you an annual Consumer Confidence Report (CCR) by July 1 each year. You can also request it directly from the utility or find it online by searching "Sioux City Water Supply Consumer Confidence Report." The EPA's ECHO database also has historical compliance data.
What water filter should I use in 51102?+
The right filter depends on what contaminants are present. For lead, look for a filter certified to NSF/ANSI Standard 53. For chlorine byproducts (like THMs), NSF/ANSI 42 filters work well. For a broad range of contaminants including PFAS, look for NSF/ANSI 58 (reverse osmosis) systems. For ZIP code 51102, with a clean compliance record, a standard carbon block filter meeting NSF/ANSI 42 is a good choice for taste and as a precaution.
Is 51102 tap water safe for babies and infants?+
Infants are especially vulnerable to lead, nitrates, and microbial contaminants in drinking water. Current EPA data for 51102 shows a lead level of 2.0 ppb — below the action level, but as an extra precaution, run your tap for 30 seconds before use and consider a certified lead filter for infant formula. Always consult your pediatrician for guidance specific to your child's health.

Data Sources & Methodology

Water quality data for ZIP code 51102 is compiled from the EPA Safe Drinking Water Information System (SDWIS), EPA ECHO enforcement database, UCMR5 unregulated contaminant monitoring, and Consumer Confidence Reports filed by Sioux City Water Supply. Safety scores are composite metrics derived from violation history, lead levels, enforcement actions, and infrastructure risk indicators. Data reflects a 5-year monitoring window. Last dataset update: 2024. View EPA source data →