States › Missouri › St. Louis County

St. Louis County, MO Water Quality

Water quality data for 2 public water systems serving St. Louis County, Missouri — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 2 water systems · 97 cities
✅
Excellent — All Systems Performing Well

Water quality across the county is outstanding with minimal violations and very low lead levels.

A

St. Louis County Earns a A

St. Louis County: 97 communities across 2 water systems. 100.0% have no open violations.

  • Median lead where detected: none detected
  • 0 communities with a lead detection, 97 reporting none detected
  • 0 communities with PFAS above the federal limit
  • 2 with significant inspection deficiencies
  • 100.0% of communities have no open violations
—
Median Lead Level
County-wide, 90th percentile
2
Water Systems
Active CWS & NTNCWS
100%
Violation-Free
No active violations on record
How we grade counties: MyWaterIQ uses EPA SDWIS enforcement data — actual MCL violations and lead test results — not the aspirational MCLG targets used by some sites. A grade reflects real compliance history, not theoretical risk. Learn more →

Cities by Water Quality

⭐ Best Performing
  • Florissant
    Not detected
    No federal limits exceeded on record
    A
  • Chesterfield
    Not detected
    No federal limits exceeded on record
    A
  • Oakville
    Not detected
    No federal limits exceeded on record
    A
  • University City
    Not detected
    No federal limits exceeded on record
    A
  • Ballwin
    Not detected
    No federal limits exceeded on record
    A
⚠ Needs Attention
  • Kirkwood
    Not detected
    1 significant inspection deficiency
    A
  • Oakland
    Not detected
    1 significant inspection deficiency
    A
  • Florissant
    Not detected
    No federal limits exceeded on record
    A
  • Chesterfield
    Not detected
    No federal limits exceeded on record
    A
  • Oakville
    Not detected
    No federal limits exceeded on record
    A

All Cities in St. Louis County

Florissant Not detected A
Chesterfield Not detected A
Oakville Not detected A
University City Not detected A
Ballwin Not detected A
Wildwood Not detected A
Mehlville Not detected A
Maryland Heights Not detected A
Kirkwood Not detected A
Hazelwood Not detected A
Webster Groves Not detected A
Affton Not detected A
Old Jamestown Not detected A
Creve Coeur Not detected A
Ferguson Not detected A
Spanish Lake Not detected A
Manchester Not detected A
Concord Not detected A
Lemay Not detected A
Clayton Not detected A
Overland Not detected A
St. Ann Not detected A
Jennings Not detected A
Town and Country Not detected A
Bridgeton Not detected A
Crestwood Not detected A
Bellefontaine Neighbors Not detected A
Ellisville Not detected A
Ladue Not detected A
Richmond Heights Not detected A
Olivette Not detected A
Sunset Hills Not detected A
Berkeley Not detected A
Brentwood Not detected A
Sappington Not detected A
Maplewood Not detected A
Valley Park Not detected A
St. John Not detected A
Black Jack Not detected A
Shrewsbury Not detected A
Des Peres Not detected A
Eureka Not detected A
Dellwood Not detected A
Rock Hill Not detected A
Glasgow Village Not detected A
Breckenridge Hills Not detected A
Glendale Not detected A
Normandy Not detected A
Fenton Not detected A
Woodson Terrace Not detected A
Northwoods Not detected A
Frontenac Not detected A
Castle Point Not detected A
Green Park Not detected A
Pine Lawn Not detected A
Clarkson Valley Not detected A
Pagedale Not detected A
Riverview Not detected A
Marlborough Not detected A
Moline Acres Not detected A
Bel-Ridge Not detected A
Warson Woods Not detected A
Hanley Hills Not detected A
Vinita Park Not detected A
Lakeshire Not detected A
St. George Not detected A
Winchester Not detected A
Wellston Not detected A
Bel-Nor Not detected A
Charlack Not detected A
Hillsdale Not detected A
Velda City Not detected A
Calverton Park Not detected A
Cool Valley Not detected A
Country Club Hills Not detected A
Grantwood Village Not detected A
Pasadena Hills Not detected A
Velda Village Hills Not detected A
Norwood Court Not detected A
Edmundson Not detected A
Bella Villa Not detected A
Flordell Hills Not detected A
Oakland Not detected A
Greendale Not detected A
Twin Oaks Not detected A
Sycamore Hills Not detected A
Crystal Lake Park Not detected A
Beverly Hills Not detected A
Wilbur Park Not detected A
Pasadena Park Not detected A
Huntleigh Not detected A
Uplands Park Not detected A
Westwood Not detected A
Kinloch Not detected A
Bellerive Acres Not detected A
Country Life Acres Not detected A
Champ Not detected A
Showing 97 cities
No active violations Active violations

About St. Louis County Drinking Water

St. Louis County is served by 2 water systems covering 97 communities. No community here has an open violation on record.

Lead was not detected in any community in St. Louis County that reported a result.

No community here has PFAS above the federal limit on record. State inspectors recorded significant deficiencies at 2 of them.

Frequently Asked Questions

Is St. Louis County tap water safe to drink?▼
No community in St. Louis County has an open violation on record. No community has PFAS above the federal limit on record.
What is the lead level in St. Louis County?▼
No community reported a lead detection.
How many water systems serve St. Louis County?▼
2 community water systems serve 97 communities here.
← Back to Missouri water quality overview