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Washington County, IL Water Quality

Water quality data for 9 public water systems serving Washington County, Illinois — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 9 water systems · 9 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

Washington County Earns a B

Washington County: 9 communities across 9 water systems. 100.0% have no open violations.

  • Median lead where detected: 2.05 ppb
  • 2 communities with a lead detection, 7 reporting none detected
  • 0 communities with PFAS above the federal limit
  • 9 with significant inspection deficiencies
  • 100.0% of communities have no open violations
2.05 ppb
Median Lead Level
County-wide, 90th percentile
9
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
  • Nashville
    Not detected
    2 significant inspection deficiencies
    A
  • Irvington
    Not detected
    2 significant inspection deficiencies
    B
  • Ashley
    1.90 ppb
    1 significant inspection deficiency
    B
  • Richview
    Not detected
    1 significant inspection deficiency
    B
  • New Minden
    Not detected
    2 significant inspection deficiencies
    B
⚠ Needs Attention
  • Okawville
    Not detected
    3 significant inspection deficiencies
    C
  • Hoyleton
    Not detected
    3 significant inspection deficiencies
    B
  • Nashville
    Not detected
    2 significant inspection deficiencies
    A
  • Irvington
    Not detected
    2 significant inspection deficiencies
    B
  • Ashley
    1.90 ppb
    1 significant inspection deficiency
    B
County Lead Level — Median 2.05 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 2.05 ppb — 13.7% of the federal action level
Systems by Lead Level
Under 5 ppb
2
No Data
7

All Cities in Washington County

Nashville Not detected A
Okawville Not detected C
Irvington Not detected B
Hoyleton Not detected B
Ashley 1.90 ppb B
Richview Not detected B
New Minden Not detected B
Radom Not detected B
Du Bois 2.20 ppb B
Showing 9 cities
No active violations Active violations

About Washington County Drinking Water

Washington County is served by 9 water systems covering 9 communities. No community here has an open violation on record.

Of the communities reporting lead results, 2 recorded a detection, with a median of 2.05 ppb — 14% of the federal action level. 7 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 9 of them.

Frequently Asked Questions

Is Washington County tap water safe to drink?▼
No community in Washington County has an open violation on record. No community has PFAS above the federal limit on record.
What is the lead level in Washington County?▼
Among communities with a detection the median is 2.05 ppb, 14% of the 15 ppb action level. 7 reported none detected and 0 reported no result.
How many water systems serve Washington County?▼
9 community water systems serve 9 communities here.
← Back to Illinois water quality overview