Mason City, IA: 2 Violations — 61/100 (2026)
2 ZIP codes · 2 water systems · Updated 2026-06-03
Across Mason City, EPA compliance data for IA sits at a moderate level — not alarming, but not uniformly clean across all service areas either.
How Mason City Compares
Data: EPA SDWIS Last verified: 2026-06-03
Mason City Water: The Quick Version
- Your city's water systems recorded 2 violations in the past 5 years.
- Average lead level: 0.0029 mg/L.
- Estimated remediation: $1,800 per household.
- CDC health risk index: 14.3 — above typical levels.
Water Systems Serving Mason City
Structurally, Mason City, IA's water supply is divided. Federal data identifies 2 water systems in the area, with 2 providers serving the bulk of residential connections. These utilities operate independently, meaning rate-setting authority and EPA compliance accountability are distributed rather than centralized.
Overview
We track water quality and home safety data for 2 ZIP codes in Mason City, Iowa, covering 2 community water systems serving approximately 28,818 people.
2 of 2 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for Mason City: C (61/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Mason City water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0029 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
- Zone 1 (High): 2 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Consumer Confidence Report Rule | Reporting | 3 | 2 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 50401 | C | 1 | 0 | Mason City Water Department |
| 50402 | C | 1 | 0 | Mason City Water Department |
All ZIP Codes in Mason City
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
CDC Health Data for Mason City
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Key Contaminants Detected in Mason City
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Mason City: Remediation Cost in Perspective
Viewed from a financial planning lens, Mason City sits in the moderate remediation-share tier — the equity impact of addressing documented issues is real, and deliberate preparation separates smooth outcomes from disruptive ones for most homeowners.
Remediation costs are moderate relative to home values in Mason City. The estimated $1,200–$2,400 range is manageable for most homeowners but still worth budgeting for. Home values are 18% below the Iowa average.
Protecting Children from Lead in Mason City
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Lead risk in Mason City appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Mason City
Over the multi-decade window covered by the National Flood Insurance Program, Mason City has accumulated 202 claims — a total that suggests more than isolated flood exposure. With 50% of ZIP codes in designated flood zones, the water-quality implications of flooding move from hypothetical to periodically relevant: treatment intake can be compromised, wells can be infiltrated, and distribution backflow can occur.
Mason City has a moderate flood history with 202 FEMA claims averaging $14,867 per payout. 50% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,800</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Mason City
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Consumer Confidence Report Rule can reduce the most common contaminant found in Mason City's water.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for Mason City, IA