Saint Mary, MO Water Safety: 50/100 (2026)
1 ZIP code · 3 water systems · Updated 2026-06-03
A meaningful share of water systems in Saint Mary have recorded health-based violations in recent MO monitoring periods — placing the city in the lower tier for tap water safety.
How Saint Mary Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Saint Mary Water
- Homes built before 1986: 61% — older plumbing may contain lead solder.
- Estimated remediation: $1,600 per household.
- CDC health risk index: 14.51 — above typical levels.
Who Supplies Your Water in Saint Mary
In Saint Mary, MO, residential water supply is distributed across multiple utilities rather than concentrated in one. The 3 leading providers out of 3 tracked systems each control their own infrastructure, file separate EPA compliance reports, and set independent rate schedules.
Overview
We track water quality and home safety data for 1 ZIP code in Saint Mary, Missouri (population ~2,350), covering 3 community water systems serving approximately 11,328 people region-wide.
No EPA violations recorded across any ZIP codes in Saint Mary — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Saint Mary: D (50/100)
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
Saint Mary water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Saint Mary
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 63673 | D | Perry County Pwsd 1 | 2,023 |
All ZIP Codes in Saint Mary
- 63673 [D]
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.
Health Outcomes in Saint Mary
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
Housing & Infrastructure in Saint Mary
With 61% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Viewed through the lens of construction era, Saint Mary is predominantly an older city — a median build year of 1971 puts most of the residential inventory in the range where pre-1986 plumbing materials were the standard.
Over half of homes in Saint Mary were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Saint Mary Homeowners
When estimated remediation is placed alongside median property values in Saint Mary, the resulting ratio is low — a finding consistent with a household financial perspective where documented issues can be addressed without a meaningful impact on overall equity position, making this market one of the more favorable contexts for remediation planning.
Remediation costs in Saint Mary are relatively low compared to home values. The $800–$2,600 estimated range is a small fraction of median property value. Home values are 23% above the Missouri average.
Lead Exposure Risk for Children in Saint Mary
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.
Practically, the structural drivers in Saint Mary — 61% pre-rule stock and citywide monitoring at or beyond the regulatory benchmark — make an in-home draw the practical way to translate aggregate averages into the specific conditions at one address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Saint Mary
Flood activity in Saint Mary is neither negligible nor at the level of the highest-exposure areas in the NFIP dataset. The 198-claim record and 100% flood zone coverage suggest a community that has experienced recurrent events but has not faced the kind of sustained, severe exposure where water-supply contamination becomes a primary public health concern. It sits in a middle range where flood history merits inclusion in any complete local water quality picture.
Saint Mary has a moderate flood history with 198 FEMA claims averaging $6,565 per payout. 100% 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>$1,600</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 Saint Mary
- 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. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 61% of homes built before 1986, lead solder is a real possibility.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Saint Mary, MO