Trinity County Lake Quality
California, 10 lakes, measured by SWRCB
Trinity County has 10 monitored lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. The 10 monitored lakes in Trinity County carry whatever clarity, phosphorus, and chlorophyll-a readings SWRCB has published, shown as reported.
Most of the county's monitored lakes are shallow, under 50 feet, which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed.
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Quick Answers for Trinity County
Planning a trip? Check special fishing regulations for Big Bear Lake — or check the official California fishing regulations.
All Lakes in Trinity County
10 lakes · 0 ranked on readings, 10 without enough sampling0 lakes ranked on readings · 10 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Max Depth | Access |
|---|---|---|---|---|---|---|---|
| Big Bear LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | 73 ft | Not recorded | |
| Deadfall LakesTrinity | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Ewing ReservoirTrinity | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Grizzly LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Lewiston LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | 65 ft | ✓ Public | |
| Papoose LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Ruth LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Sapphire LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Stoddard LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | 84 ft | Not recorded | |
| Trinity LakeTrinity | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded |
NR = no nutrient or algae reading on record. The measurements are published as the authority reports them. Where the data comes from.
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Source: the California State Water Resources Control Board. See data sources.