O Fallon, MO: 10 Violations - Home Safety 63/100
2 ZIP codes · 5 water systems · Updated
ZipCheckup grade for O Fallon: C.
A mixed picture - some signals here are worth your attention.
O Fallon earns a C grade for MO; check the EPA record for the system that serves your address.
How O Fallon Compares
Data: EPA SDWIS
What You Should Know About O Fallon Water
- Your city's water systems recorded 10 violations since 2021.
- Average of reported 90th-percentile lead results: 0.0029 mg/L.
- Homes built before 1986: 19% - older plumbing may contain lead solder.
- Estimated remediation: $500 per household.
- Health risk index (ZipCheckup composite of CDC data): 11.99.
Who Supplies Your Water in O Fallon
When a city is linked to 5 water systems, as O Fallon, MO is in federal records, water in one neighborhood may come from a different system than in another. The 3 systems with the largest reported populations are shown below, and their compliance records are kept separately, so a violation logged for one does not describe the others.
- C
- C
- C
Overview
We track home safety data for 2 ZIP codes in O Fallon, Missouri (population ~100,311), covering 5 community water systems serving approximately 1,287,586 people region-wide. The EPA snapshots used for this build directly map water systems to 2 of 2 ZIP codes.
2 of 2 ZIP codes with a reported violation count in the available EPA record (100%) have recorded EPA violations. The available record reports no health-based violations for this measured scope.
Home Safety Score
Average Home Safety Score for O Fallon: C (63/100)
Model 4.0.0 uses four measured components across three equally weighted domains. If a required domain is unavailable, no score is published:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| PFAS MCL Screen | UCMR 5 testing against the covered federal MCLs |
| Radon Risk | EPA radon zone classification |
| Annual AQI | EPA AirData county-year median with at least 90 observed days |
Water Sources
O Fallon water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average of reported 90th-percentile lead results: 0.0029 mg/L (EPA action level: 0.015 mg/L)
- 0 of 2 ZIP codes with known status exceed the EPA lead action level
Radon Risk
2 of 2 ZIP records with known zones are in EPA Radon Zone 2.
The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Lead and Copper Rule | Treatment Technique | 6 | 1 |
| Consumer Confidence Rule | Reporting | 6 | 1 |
| Groundwater Rule | Treatment Technique | 5 | 2 |
| Revised Total Coliform Rule | Microbiological | 3 | 2 |
| Lead and Copper Rule Revisions | Treatment Technique | 2 | 1 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 63366 | C | 10 | 0 | St Charles County Pwsd 2 |
| 63368 | C | 2 | 0 | St Charles County Pwsd 2 |
All ZIP Codes in O Fallon
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
Reporting periods vary by source. Missing data is shown as unavailable, not as zero.
Health Outcomes in O Fallon
Source: CDC PLACES (County-level estimates). County health indicators are shown for context only and are not linked to this area's water records.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Top Contaminants in O Fallon Water
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Housing & Infrastructure in O Fallon
Housing age data helps assess potential lead pipe and infrastructure risks. Newer housing stock generally means lower plumbing-related contamination risk.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Utilities keep service line inventories, which can show whether an address in O Fallon has a lead line regardless of the 1991 median build year.
Most homes in O Fallon were built after 1986; lead exposure at a tap still depends on its service line and plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for O Fallon Homeowners
Of the three cost-context tiers - low, moderate and elevated - O Fallon is in the low one.
Estimated remediation costs in O Fallon can be compared with local home values. The $300–$800 estimated range can be set against the median property value; actual costs vary by home. Home values are 87% above the Missouri average.
Lead Exposure Risk for Children in O Fallon
Why children are most at risk: The CDC states that no safe blood lead level in children has been identified. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
19% of the O Fallon housing stock dates from before 1986, the year Congress limited lead in pipes, solder and flux. Water systems report lead as the 90th percentile of their tap samples, and the average of those results across the city's ZIP codes is below 0.010 mg/L. Because lead in drinking water usually comes from corrosion of a building's own service line and plumbing, that average cannot stand in for a single address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Historical NFIP Claim Context in O Fallon
Historical NFIP data for O Fallon contains 347 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $24,243. Among ZIP codes with claim records, 100% have an A- or V-family dominant rated zone recorded in those historical claims. This is not a complete current FEMA property-map inventory.
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. The $500 remediation estimate shown here excludes flood insurance and is not derived from NFIP claim count.
Claim count does not establish current property risk. Check the exact address in FEMA's current map and obtain a property-specific insurance quote when relevant.
Source: historical FEMA National Flood Insurance Program (NFIP) claim records. No current FEMA property-map designation is asserted.
What You Can Do in O Fallon
- Test your water at home. City-level data shows averages - your tap may differ. Check the certification, price and turnaround time of any water test kit or lab service.
- Install a certified water filter. For Lead and Copper Rule, listed in the water-quality records for O Fallon: if it is a rule or reporting requirement rather than a contaminant, ask your utility what the record involved; for bacteria, follow any boil-water notice from your utility; for a specific chemical contaminant, check whether a filter is certified to reduce it. Not every contaminant has a consumer filter certification.
- 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 O Fallon, MO