Lake Saint Louis, MO Water Safety: 55/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-04
Within Lake Saint Louis, water safety data for MO reveals moderate quality — federal standards are generally met, but documented exceptions exist in specific service areas.
How Lake Saint Louis Compares
Data: EPA SDWIS Last verified: 2026-06-04
What You Should Know About Lake Saint Louis Water
- Homes built before 1986: 24% — older plumbing may contain lead solder.
- Estimated remediation: $1,600 per household.
- CDC health risk index: 11.99.
Who Supplies Your Water in Lake Saint Louis
Lake Saint Louis, MO draws its residential water from 2 separate providers among the 2 federally tracked systems. Each operates independently, with its own infrastructure, rate structure, and compliance record.
Overview
We track water quality and home safety data for 1 ZIP code in Lake Saint Louis, Missouri (population ~27,893), covering 2 community water systems serving approximately 142,371 people region-wide.
No EPA violations recorded across any ZIP codes in Lake Saint Louis — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Lake Saint Louis: C (55/100)
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
Lake Saint Louis water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Lake Saint Louis
- 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 |
|---|---|---|---|
| 63367 | C | ST CHARLES COUNTY PWSD 2 | 100,587 |
All ZIP Codes in Lake Saint Louis
- 63367 [C]
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 Lake Saint Louis
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 Lake Saint Louis
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
Lake Saint Louis's housing stock skews relatively recent, with a median build year of 2007. Homes constructed after 1986 avoid the lead-soldered copper joints that were standard before the federal ban — reducing aggregate risk from plumbing as a contamination pathway.
Most homes in Lake Saint Louis were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Lake Saint Louis Homeowners
In Lake Saint Louis, documented water and safety issues can be addressed without making a meaningful dent in home equity — the financial proportionality here is favorable, and the commitment fits within standard property planning frameworks.
Remediation costs in Lake Saint Louis are relatively low compared to home values. The $800–$2,600 estimated range is a small fraction of median property value. Home values are 117% above the Missouri average.
Lead Exposure Risk for Children in Lake Saint Louis
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.
Pre-rule stock in Lake Saint Louis accounts for 24% of the inventory — a modest fraction — and citywide samples land safely beneath the federal action mark.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Lake Saint Louis
Flood activity in Lake Saint Louis is neither negligible nor at the level of the highest-exposure areas in the NFIP dataset. The 14-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.
Lake Saint Louis has a moderate flood history with 14 FEMA claims averaging $2,671 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 Lake Saint Louis
- 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. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for Lake Saint Louis, MO