States › Missouri › Mercer County

Mercer County, MO Water Quality

Water quality data for 3 public water systems serving Mercer County, Missouri — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 3 water systems · 4 cities
✅
Generally Safe — Most Systems Performing Well

The majority of water systems have no active violations and lead levels well below the federal action level.

B

Mercer County Earns a B

Mercer County: 4 communities across 3 water systems. 100.0% have no open violations.

  • Median lead where detected: 13.66 ppb
  • 1 communities with a lead detection, 3 reporting none detected
  • 0 communities with PFAS above the federal limit
  • 1 with significant inspection deficiencies
  • 100.0% of communities have no open violations
13.66 ppb
Median Lead Level
County-wide, 90th percentile
3
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
  • Princeton
    Not detected
    No federal limits exceeded on record
    B
  • Ravanna
    Not detected
    1 health-based violation since 2015
    A
  • South Lineville
    Not detected
    1 health-based violation since 2015
    A
  • Mercer
    13.66 ppb
    1 significant inspection deficiency
    C
⚠ Needs Attention
  • Mercer
    13.66 ppb
    1 significant inspection deficiency
    C
  • Ravanna
    Not detected
    1 health-based violation since 2015
    A
  • South Lineville
    Not detected
    1 health-based violation since 2015
    A
  • Princeton
    Not detected
    No federal limits exceeded on record
    B
County Lead Level — Median 13.66 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 13.66 ppb — 91.1% of the federal action level
Systems by Lead Level
10 – 15 ppb
1
No Data
3

All Cities in Mercer County

Princeton Not detected B
Mercer 13.66 ppb C
Ravanna Not detected A
South Lineville Not detected A
Showing 4 cities
No active violations Active violations

About Mercer County Drinking Water

Mercer County is served by 3 water systems covering 4 communities. No community here has an open violation on record.

Of the communities reporting lead results, 1 recorded a detection, with a median of 13.66 ppb — 91% of the federal action level. 3 reported none detected, which means below the laboratory limit rather than an absence of lead.

No community here has PFAS above the federal limit on record. State inspectors recorded significant deficiencies at 1 of them.

Frequently Asked Questions

Is Mercer County tap water safe to drink?▼
No community in Mercer County has an open violation on record. No community has PFAS above the federal limit on record.
What is the lead level in Mercer County?▼
Among communities with a detection the median is 13.66 ppb, 91% of the 15 ppb action level. 3 reported none detected and 0 reported no result.
How many water systems serve Mercer County?▼
3 community water systems serve 4 communities here.
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