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Fremont County, WY Water Quality

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

📅 2026 Report 🔄 Data updated 2026 Q2 📍 10 water systems · 11 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

Fremont County Earns a B

Fremont County: 11 communities across 10 water systems. 100.0% have no open violations.

  • Median lead where detected: 4.00 ppb
  • 6 communities with a lead detection, 5 reporting none detected
  • 1 communities with PFAS above the federal limit
  • 3 with significant inspection deficiencies
  • 100.0% of communities have no open violations
4 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
  • Fort Washakie
    4.00 ppb
    No federal limits exceeded on record
    A
  • Shoshoni
    4.00 ppb
    No federal limits exceeded on record
    B
  • Boulder Flats
    4.00 ppb
    No federal limits exceeded on record
    A
  • Lander
    3.00 ppb
    1 health-based violation since 2015
    A
  • Hudson
    Not detected
    Copper above the 1,300 ppb action level
    B
⚠ Needs Attention
  • Ethete
    1.00 ppb
    Copper above the 1,300 ppb action level
    C
  • Riverton
    4.00 ppb
    PFAS above the limit at 1 of 13 sampling points
    C
  • Pavillion
    Not detected
    1 significant inspection deficiency
    C
  • Arapahoe
    Not detected
    2 significant inspection deficiencies
    B
  • Dubois
    Not detected
    Copper above the 1,300 ppb action level
    B
County Lead Level — Median 4 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 4 ppb — 26.7% of the federal action level
Systems by Lead Level
Under 5 ppb
6
No Data
5

All Cities in Fremont County

Riverton 4.00 ppb C
Lander 3.00 ppb A
Fort Washakie 4.00 ppb A
Arapahoe Not detected B
Ethete 1.00 ppb C
Dubois Not detected B
Shoshoni 4.00 ppb B
Hudson Not detected B
Boulder Flats 4.00 ppb A
Pavillion Not detected C
Jeffrey City Not detected B
Showing 11 cities
No active violations Active violations

About Fremont County Drinking Water

Fremont County is served by 10 water systems covering 11 communities. No community here has an open violation on record.

Of the communities reporting lead results, 6 recorded a detection, with a median of 4.00 ppb — 27% of the federal action level. 5 reported none detected, which means below the laboratory limit rather than an absence of lead.

1 of 11 communities have PFAS above the limits EPA set in 2024, measured as a running annual average at each sampling point. State inspectors recorded significant deficiencies at 3 of them.

Frequently Asked Questions

Is Fremont County tap water safe to drink?▼
No community in Fremont County has an open violation on record. 1 of 11 have PFAS above the federal limit, which is the main open concern.
What is the lead level in Fremont County?▼
Among communities with a detection the median is 4.00 ppb, 27% of the 15 ppb action level. 5 reported none detected and 0 reported no result.
How many water systems serve Fremont County?▼
10 community water systems serve 11 communities here.
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