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Rock Island County, IL Water Quality

Water quality data for 20 public water systems serving Rock Island County, Illinois — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 20 water systems · 21 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

Rock Island County Earns a B

Rock Island County: 21 communities across 20 water systems. 95.2% have no open violations.

  • Median lead where detected: 2.52 ppb
  • 10 communities with a lead detection, 11 reporting none detected
  • 0 communities with PFAS above the federal limit
  • 16 with significant inspection deficiencies
  • 95.2% of communities have no open violations
2.52 ppb
Median Lead Level
County-wide, 90th percentile
20
Water Systems
Active CWS & NTNCWS
95%
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
  • Rock Island
    Not detected
    No federal limits exceeded on record
    A
  • Coyne Center
    0.80 ppb
    No federal limits exceeded on record
    B
  • Moline
    2.40 ppb
    1 significant inspection deficiency
    A
  • Port Byron
    4.70 ppb
    Copper above the 1,300 ppb action level
    B
  • Hillsdale
    Not detected
    1 significant inspection deficiency
    B
⚠ Needs Attention
  • Coal Valley
    Not detected
    Copper above the 1,300 ppb action level
    C
  • Silvis
    1.70 ppb
    1 violation currently open
    C
  • Andalusia
    3.00 ppb
    Copper above the 1,300 ppb action level
    C
  • Carbon Cliff
    Not detected
    2 significant inspection deficiencies
    C
  • Oak Grove
    2.63 ppb
    4 significant inspection deficiencies
    C
County Lead Level — Median 2.52 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 2.52 ppb — 16.8% of the federal action level
Systems by Lead Level
Under 5 ppb
8
10 – 15 ppb
2
No Data
11

All Cities in Rock Island County

Moline 2.40 ppb A
Rock Island Not detected A
East Moline 10.00 ppb B
Silvis 1.70 ppb C
Milan Not detected B
Coal Valley Not detected C
Hampton 1.30 ppb B
Carbon Cliff Not detected C
Andalusia 3.00 ppb C
Port Byron 4.70 ppb B
Cordova Not detected B
Reynolds Not detected B
Edgington Not detected B
Oak Grove 2.63 ppb C
Hillsdale Not detected B
Rapids City Not detected B
Coyne Center 0.80 ppb B
Barstow 10.00 ppb B
Illinois City 0.80 ppb B
Rock Island Arsenal Not detected B
Taylor Ridge Not detected B
Showing 21 cities
No active violations Active violations

About Rock Island County Drinking Water

Rock Island County is served by 20 water systems covering 21 communities. 95% have no open violations.

Of the communities reporting lead results, 10 recorded a detection, with a median of 2.52 ppb — 17% of the federal action level. 11 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 16 of them.

Frequently Asked Questions

Is Rock Island County tap water safe to drink?▼
95% of communities have no open violation. No community has PFAS above the federal limit on record.
What is the lead level in Rock Island County?▼
Among communities with a detection the median is 2.52 ppb, 17% of the 15 ppb action level. 11 reported none detected and 0 reported no result.
How many water systems serve Rock Island County?▼
20 community water systems serve 21 communities here.
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