
Sonoma County Lake Quality
California, 6 lakes, measured by SWRCB
Sonoma County holds 6 monitored lakes. With a sample that small the county-level summary describes those specific waters, not necessarily every water body in the county. The 6 monitored lakes in Sonoma 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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Top-rated places to stay near Sonoma County
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Quick Answers for Sonoma County
Planning a trip? Check special fishing regulations for Laguna Lake — or check the official California fishing regulations.
All Lakes in Sonoma County
6 lakes · 0 ranked on readings, 6 without enough sampling0 lakes ranked on readings · 6 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| Laguna LakeSonoma | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Lake IlsanjoSonoma | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Lake SonomaSonoma | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Lytton LakeSonoma | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Merlo LakeSonoma | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Santa Rosa Creek ReservoirSonoma | 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.