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Trinity County, CA Water Quality

Water quality data for 8 public water systems serving Trinity County, California — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 8 water systems · 9 cities
⚠️
Caution Advised — Some Systems Need Attention

Some systems have elevated lead levels or active violations. Check your specific city below.

C

Trinity County Earns a C

Trinity County: 9 communities across 8 water systems. 77.8% have no open violations.

  • Median lead where detected: 2.69 ppb
  • 7 communities with a lead detection, 2 reporting none detected
  • 2 communities with PFAS above the federal limit
  • 0 with significant inspection deficiencies
  • 77.8% of communities have no open violations
2.69 ppb
Median Lead Level
County-wide, 90th percentile
8
Water Systems
Active CWS & NTNCWS
77%
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
  • Hayfork
    Not detected
    No federal limits exceeded on record
    B
  • Trinity Center
    1.82 ppb
    No federal limits exceeded on record
    B
  • Trinity Village
    2.00 ppb
    1 health-based violation since 2015
    B
  • Burnt Ranch
    0.60 ppb
    2 health-based violations since 2015
    B
  • Lewiston
    2.69 ppb
    3 health-based violations since 2015
    B
⚠ Needs Attention
  • Coffee Creek
    21.50 ppb
    Lead above the 15 ppb action level
    F
  • Weaverville
    11.70 ppb
    PFAS above the limit at 1 of 3 sampling points
    D
  • Douglas City
    11.70 ppb
    PFAS above the limit at 1 of 3 sampling points
    D
  • Salyer
    Not detected
    1 violation currently open
    C
  • Lewiston
    2.69 ppb
    3 health-based violations since 2015
    B
County Lead Level — Median 2.69 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 2.69 ppb — 17.9% of the federal action level
Systems by Lead Level
Under 5 ppb
4
10 – 15 ppb
3
No Data
2

All Cities in Trinity County

Weaverville 11.70 ppb D
Hayfork Not detected B
Lewiston 2.69 ppb B
Douglas City 11.70 ppb D
Trinity Village 2.00 ppb B
Trinity Center 1.82 ppb B
Burnt Ranch 0.60 ppb B
Salyer Not detected C
Coffee Creek 21.50 ppb F
Showing 9 cities
No active violations Active violations

About Trinity County Drinking Water

Trinity County is served by 8 water systems covering 9 communities. 78% have no open violations.

Of the communities reporting lead results, 7 recorded a detection, with a median of 2.69 ppb — 18% of the federal action level. 2 reported none detected, which means below the laboratory limit rather than an absence of lead.

2 of 9 communities have PFAS above the limits EPA set in 2024, measured as a running annual average at each sampling point. State inspectors recorded no significant deficiencies.

Frequently Asked Questions

Is Trinity County tap water safe to drink?▼
78% of communities have no open violation. 2 of 9 have PFAS above the federal limit, which is the main open concern.
What is the lead level in Trinity County?▼
Among communities with a detection the median is 2.69 ppb, 18% of the 15 ppb action level. 2 reported none detected and 0 reported no result.
How many water systems serve Trinity County?▼
8 community water systems serve 9 communities here.
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