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Green County, WI Water Quality

Water quality data for 10 public water systems serving Green County, Wisconsin — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 10 water systems · 17 cities
✅
Excellent — All Systems Performing Well

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

A

Green County Earns a A

Green County: 17 communities across 10 water systems. 100.0% have no open violations.

  • Median lead where detected: 1.02 ppb
  • 15 communities with a lead detection, 2 reporting none detected
  • 0 communities with PFAS above the federal limit
  • 1 with significant inspection deficiencies
  • 100.0% of communities have no open violations
1.02 ppb
Median Lead Level
County-wide, 90th percentile
10
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
  • Brooklyn
    0.78 ppb
    No federal limits exceeded on record
    B
  • Monroe
    4.70 ppb
    No federal limits exceeded on record
    A
  • Brodhead
    1.02 ppb
    No federal limits exceeded on record
    B
  • Albany
    0.56 ppb
    No federal limits exceeded on record
    B
  • Decatur
    1.02 ppb
    No federal limits exceeded on record
    B
⚠ Needs Attention
  • Exeter
    1.50 ppb
    1 significant inspection deficiency
    B
  • Mount Pleasant
    0.25 ppb
    1 health-based violation since 2015
    B
  • Washington
    0.25 ppb
    1 health-based violation since 2015
    B
  • New Glarus
    Not detected
    1 health-based violation since 2015
    B
  • Monticello
    0.25 ppb
    1 health-based violation since 2015
    B
County Lead Level — Median 1.02 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 1.02 ppb — 6.8% of the federal action level
Systems by Lead Level
Under 5 ppb
15
No Data
2

All Cities in Green County

Monroe 4.70 ppb A
Brodhead 1.02 ppb B
New Glarus Not detected B
Monticello 0.25 ppb B
Albany 0.56 ppb B
Decatur 1.02 ppb B
Browntown 2.48 ppb B
Monroe 2.50 ppb B
Cadiz 2.65 ppb B
Jordan 2.65 ppb B
New Glarus Not detected B
Clarno 4.70 ppb A
Albany 0.56 ppb B
Washington 0.25 ppb B
Brooklyn 0.78 ppb B
Exeter 1.50 ppb B
Mount Pleasant 0.25 ppb B
Showing 17 cities
No active violations Active violations

About Green County Drinking Water

Green County is served by 10 water systems covering 17 communities. No community here has an open violation on record.

Of the communities reporting lead results, 15 recorded a detection, with a median of 1.02 ppb — 7% of the federal action level. 2 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 Green County tap water safe to drink?▼
No community in Green County has an open violation on record. No community has PFAS above the federal limit on record.
What is the lead level in Green County?▼
Among communities with a detection the median is 1.02 ppb, 7% of the 15 ppb action level. 2 reported none detected and 0 reported no result.
How many water systems serve Green County?▼
10 community water systems serve 17 communities here.
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