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LakeQuality
Late afternoon sun over Slim Lake, scattering a bright path across wind-textured water

Lassen County Lake Quality

California, 71 lakes, measured by SWRCB

Lassen County has 71 monitored lakes, enough that within-county variation matters as much as the county average. Some are deep glacial basins, others are shallow agricultural-watershed waters, and the measurements reflect that mix. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. Phosphorus and algae readings vary widely across Lassen County; the per-lake pages below carry the numbers.

The county's lakes lean shallow, which makes the readings sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest measured lake is Eagle Lake.

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Top-rated places to stay near Lassen County

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Quick Answers for Lassen County

Cleanest lakes in Lassen County →Best swimming lakes in California →

Planning a trip? Check special fishing regulations for Eagle Lake — or check the official California fishing regulations.

All Lakes in Lassen County

71 lakes · 1 ranked on readings, 70 without enough sampling1 lake ranked on readings · 70 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicAccess
1Eagle LakeLassenNo recent samples248 µg/LNo recent samplesNo recent samplesNot recorded
Ashurst LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Bear LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Bear Valley ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Big Jack LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Biscar ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Blue LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Boot LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Branham ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Buckhorn ReservoirLassenNo recent samplesNo recent samples8.9 µg/LNo recent samplesNot recorded
Butte LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Calneva LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Caribou LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Catfish ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Cleghorn ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Corders ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Cow LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Coyote ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Craemer ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Crater LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Crum ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Dillion LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Dodge ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Dry LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Emerson LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Feather LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Gordon LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Hartson LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Heath Dam ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Hog Flat ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Holbrook ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Homer LakeLassenNo recent samples5 µg/LNo recent samplesNo recent samplesNot recorded
Honey LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Hoover Flat ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Horse LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Juniper LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake LeavittLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lane ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Little Cleghorn ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Long LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lower Dry LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Mahogany LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
McCoy Flat ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Mendiboure ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Moll ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Moon LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Mountain Meadows ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Mud LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Nelson Corral ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Newland ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Nine Springs ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Poison LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Red Rock LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Round Corral ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Round Valley ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Said Valley ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Schrode LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Silva Flat ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Silver LakeLassenNo recent samples11 µg/LNo recent samplesNo recent samplesNot recorded
Smoke Creek ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Snag LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Snider LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Spooner ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Straylor LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Summit LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Swanberger ReservoirLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Triangle LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Turnaround LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Twin LakesLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Van Sickle LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Wards LakeLassenNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot 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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Other Counties in California

Plumas County

19 lakes

Amador County

12 lakes

Placer County

16 lakes

Butte County

16 lakes

Nevada County

35 lakes

Santa Clara County

13 lakes

Browse every California lake, or the full directory of lakes across all United States (49 states), Canada (Ontario, Québec, Nova Scotia, British Columbia and Newfoundland and Labrador), and 38 other country hubs..

Source: the California State Water Resources Control Board. See data sources.