A
95

Excellent Water Quality

Saint Louis, MO 63135

Saint Louis County · Population served: 1,111,000 · Data updated March 2026

Water Systems Serving This Area

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MO AMERICAN ST LOUIS ST CHARLES COUNTIES
Surface water · Pop. 1,111,000
PWSID: MO6010716

Contaminants Detected

ContaminantDetected LevelEPA MCLHealth GuidelineStatus
Lead
3.0
15 ppb 1 ppb Warning

PFAS / Forever Chemicals

1 detected All below limits
CompoundLevelEPA MCLHealth GuidelineStatus
PFBA5.1 pptNo standard500 pptUnregulated

Water Quality Summary

Understanding Your Water in Saint Louis

Tap water quality in Saint Louis, Missouri (63135) receives an overall grade of A (Excellent) with a score of 95 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is 15 points above the Missouri state average of 80. Compared to the national average (75), this area performs significantly better. The area is served by Mo American St Louis St Charles Counties, a surface water system providing water to approximately 1,111,000 people. Testing has found elevated levels of Lead that warrant attention. PFAS testing detected 1 compound, all currently below EPA limits. The area has a clean violation record over the past 5 years — a positive indicator of consistent water quality management.

Your Score 95/100 A
vs State 15 pts above Missouri avg (80)
vs National 20 pts above national avg (75)

What a Grade A Means

A score of 95/100 means the water supply in Saint Louis, MO meets or exceeds all EPA standards with minimal issues. Contaminant levels are well within safe limits, and the water system has maintained a strong compliance record. While no water supply is guaranteed perfect at the tap due to household plumbing, this is among the best-scoring areas in the country.

Surface water: sourced from rivers, lakes, or reservoirs

Health Information

What These Contaminants Mean for You

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Lead in Your Water

Lead is a toxic metal that can leach from aging pipes and plumbing fixtures.

Health Effects

Even low levels of lead exposure can cause developmental delays in children, kidney damage, and cardiovascular effects in adults. The EPA action level is 15 ppb, but health experts recommend no safe level of lead in drinking water.

Common Sources

Lead enters water primarily through corrosion of lead service lines, lead solder, and brass fixtures — especially in homes built before 1986.

What You Can Do

If lead is detected above 1 ppb, consider using a certified lead-removal filter (NSF/ANSI 53) for drinking and cooking water. Run cold water for 30 seconds before use if water has been sitting in pipes.

Common Questions

Frequently Asked Questions

Based on EPA data, tap water in Saint Louis, Missouri receives a grade of A (Excellent) with a score of 95/100. This indicates the water meets federal standards and has relatively few concerns. However, individual homes may still have localized issues such as lead from old plumbing.

ZIP code 63135 is served by 1 water system using surface water sources, providing water to approximately 1,111,000 people. Surface water systems are more susceptible to contamination from agricultural runoff, industrial discharge, and weather events, but typically undergo more extensive treatment including filtration and disinfection.

Lead was detected at 3.0 ppb in Saint Louis, Missouri. While this is below the EPA action level of 15 ppb, it exceeds the health guideline of 1 ppb recommended by health organizations. Consider a certified lead filter, especially if you have young children.

1 PFAS compound were detected in water serving Saint Louis, Missouri, but all are currently below EPA limits. While levels are within regulatory standards, some health organizations recommend minimizing any PFAS exposure. Activated carbon or reverse osmosis filters can reduce PFAS levels.

Water systems serving Saint Louis, Missouri have zero violations in the last 5 years. This is a positive indicator of consistent regulatory compliance and water quality management.

Based on detected contaminants (lead, PFAS), residents in Saint Louis, Missouri should consider: Reverse osmosis (RO) system — most effective for PFAS, lead, and other contaminants. Always look for filters with NSF/ANSI certification for the specific contaminants you want to remove.

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