Trinity, CA
Transparent derived index from EPA TRI / SDWIS / Superfund extracts: not an official EPA rating. Fixed caps: facilities ≤25 pts (50+ = max), log10 releases ≤25 pts, Superfund ≤25 pts (5/site), health-violation systems ≤15 pts (3/system), high-chemical facilities ≤10 pts. Bands: High ≥60, Moderate ≥30. See methodology.
Environmental data for Trinity in California · Population: 15,886
SDWIS systems such as WEAVERVILLE C.S.D.; TRINITY CO. W.W. DIST #1; R-WILD HORSE RANCH anchor Trinity, CA's EPA extract. Derived burden score 15/100 (Low Risk) uses fixed national caps on density, log release volume, Superfund count, and health-flagged systems - not an official EPA rating.
No TRI Form R facilities sit in Trinity in this extract; water coverage still lists WEAVERVILLE C.S.D.; TRINITY CO. W.W. DIST #1; R-WILD HORSE RANCH. AQS monitors logged median AQI 31 / peak 113 in 2024.
Burden score 15/100 (Low Risk) is the only weighted composite on this page. The tables below list every TRI facility, SDWIS system, and Superfund site EPA has on record for Trinity -- not just the names called out above -- reproducing the disclosure history as filed, not a current-safety verdict. Extract current as of 2026-08-25.
Air Quality History (2020–2024)
EPA Air Quality Index (AQI) data showing how many days per year fall into each air quality category.
| Year | Good | Moderate | Unhealthy (SG) | Max AQI |
|---|---|---|---|---|
| 2024 | 258 (72%) | 98 | 1 | 113 |
| 2023 | 209 (67%) | 93 | 6 | 174 |
| 2022 | 227 (64%) | 111 | 5 | 342 |
| 2021 | 201 (61%) | 81 | 4 | 1217 |
| 2020 | 215 (63%) | 100 | 12 | 211 |
Source: EPA Air Quality System (AQS) Annual AQI by County AQI categories: Good (0-50), Moderate (51-100), Unhealthy for Sensitive Groups (101-150), Unhealthy (151-200), Very Unhealthy (201-300), Hazardous (301+)
For real-time air quality readings and pollutant breakdowns in California, see the EPA's AirNow.gov.
Water Systems (14)
| System | System pop (SDWIS) | Violations |
|---|---|---|
| WEAVERVILLE C.S.D. | 3,975 | 3 |
| TRINITY CO. W.W. DIST #1 | 2,324 | 0 |
| R-WILD HORSE RANCH | 1,055 | 1 |
| TRINITY CENTER M.W.C. | 729 | 1 |
| LEWISTON COMMUNITY SERVICES DISTRICT | 677 | 7 |
| TRINITY KNOLLS MUTUAL WATER COMPANY | 338 | 1 |
| TRINITY VILLAGE MUTUAL WATER | 332 | 3 |
| SALYER MUTUAL WC (FORMERLY RIVERVIEW AC) | 231 | 3 |
| TREASURE CREEK WOODS MWC | 131 | 1 |
| SALYER HEIGHTS W.S., INC | 130 | 8 |
| BURNT RANCH ESTATES | 115 | 3 |
| RUSH CREEK MUTUAL WATER SYSTEM | 102 | 6 |
| LAKESHORE VILLA MUTUAL WATER CO | 88 | 0 |
| SEYMOUR'S MUTUAL WATER SYSTEM | 40 | 1 |
Cities in Trinity (9)
Frequently Asked Questions
What is the environmental risk level in Trinity, California? ▼
Are there Superfund sites in Trinity? ▼
How many toxic release facilities are in Trinity? ▼
What is the air quality in Trinity? ▼
Is the drinking water safe in Trinity? ▼
What environmental agencies cover Trinity? ▼
What does this county environmental profile show?
This county environmental profile rolls up EPA Toxics Release Inventory facility reports, Safe Drinking Water Information System public-water-system filings, and Superfund National Priorities List sites for the county boundary defined by the U.S. Census Bureau. Facility counts reflect facilities with a reporting address inside the county, not where downstream environmental effects may be observed. Population figures are from the most recent Census ACS 5-year estimate. The county detail page is updated whenever the upstream EPA programs publish revised data; see the methodology page for the documented ingest cadence and the editorial choices governing how aggregations are computed.
Read our methodology - how this data is sourced, computed, and verified.