SwimZone

Lake · Tuolumne County · CA

Is Cherry Lake safe to swim?

No advisory

No advisory or algae bloom reported for this water today.

Updated August 20, 2026 · EPA CyAN satellite

Recent rain (modeled)
0.0 in
Water type
Lake
Last updated
Aug 20
Bacteria
E. coli, fecal
Not monitored
Tested
Not monitored

No bacteria advisory or sampling for this water.

Blue-green algae
cyanobacteria
No advisory
Tested
None detected
Advisory over
100,000
cells/mL

No blue-green algae bloom detected in the latest clear satellite image. This is a satellite estimate, not a safety guarantee, and does not replace an official advisory.

Satellite estimate · imaged Aug 19 · EPA CyAN satellite · moderate confidence
An estimate from EPA CyAN satellite imagery, not a water sample or an official advisory. Check your state or county health department for the official status. Report a data question.

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Cherry Lake is clear today. Be the first to know when it's not.

SwimZone checks this water every day and pings you the moment a bacteria or algae advisory goes up.

What's in the water at Cherry Lake right now

As of August 20, 2026, Cherry Lake in Tuolumne County, California has no advisory posted. EPA's CyAN satellite detected no blue-green algae bloom in the latest clear image (August 19, 2026), which is an estimate, not a guarantee. Modeled rainfall over the past week was about 0.0 in (Open-Meteo, a gridded estimate that can differ from a local gauge), which can wash bacteria and nutrients into the water.

How this read is built

Blue-green algae at Cherry Lake

Cherry Lake is a lake in Tuolumne County, California covering about 2.7 sq mi, the 51st-largest of the 186 lakes SwimZone monitors in California. EPA's CyAN satellite detected no blue-green algae bloom in the latest clear image (August 19, 2026), which is an estimate, not a guarantee.

Blue-green algae (cyanobacteria) blooms are most common from midsummer into early fall, when the water is warm, calm, and rich in nutrients from runoff. They can produce toxins that make people sick and can be rapidly fatal to dogs, so skip water that looks green, scummy, or like spilled paint, and keep children and pets out of it.

Bloom history at Cherry Lake

From EPA CyAN's satellite archive

2020: peak satellite estimate about 43,000 cells/mL, below the bloom-level threshold20212022: peak satellite estimate about 25,000 cells/mL, below the bloom-level threshold22232024: peak satellite estimate about 19,000 cells/mL, below the bloom-level threshold242025: peak satellite estimate about 27,000 cells/mL, below the bloom-level threshold252026: peak satellite estimate about 13,000 cells/mL, below the bloom-level threshold26Bloom level~100k cells/mL

Each bar is that summer's peak EPA CyAN satellite estimate (log scale); the red cap is the part above the bloom-level threshold. Satellite estimates, not water samples or posted advisories.

Over 7 summers of EPA CyAN satellite imagery since 2020, Cherry Lake has not shown a satellite-estimated bloom-level signal. This is an estimate, not a guarantee, and conditions can change quickly, so check the current read and official advisories before you swim.

When to swim at Cherry Lake

It is currently peak season for blue-green algae, when warm, calm water lets blooms form fastest. This water has no recorded advisory-level bloom in its satellite history, which makes it a comparatively steady summer swim spot; conditions still change between samples, so check the current read before you go.

Frequently asked: swimming in Cherry Lake

Is it safe to swim in Cherry Lake right now?
Cherry Lake has no advisory posted today. EPA's CyAN satellite detected no blue-green algae bloom in the latest clear image (August 19, 2026), which is an estimate, not a guarantee. Conditions can change quickly with wind, heat, and rain, so check the posted signs and look at the water before you get in.
Does Cherry Lake have blue-green algae (cyanobacteria)?
EPA's CyAN satellite detected no blue-green algae bloom at Cherry Lake in the latest clear image (August 19, 2026). This is a satellite estimate below the sensor's detection limit, not a guarantee: cyanobacteria can appear within hours in warm, calm, nutrient-rich water, so look before you swim.
Can dogs swim in Cherry Lake?
No bloom is detected at Cherry Lake today, but dogs are much more vulnerable to blue-green algae than people, and blooms can form within hours. Always keep dogs away from water that looks green, scummy, or discolored, and rinse them off after swimming.
How often does Cherry Lake have blue-green algae blooms?
Over 7 summers of EPA CyAN satellite imagery since 2020, Cherry Lake has not shown a satellite-estimated bloom-level signal. This is an estimate, not a guarantee, and conditions can change quickly, so check the current read and official advisories before you swim.
How many California lakes and beaches are unsafe for swimming today?
Today, 0 California waters are above a safe-contact threshold and 21 more warrant caution, out of 445 monitored waters SwimZone tracks in the state.
How is Cherry Lake's water quality measured?
SwimZone builds this read from EPA CyAN satellite imagery for blue-green algae, official beach and fecal-bacteria advisories where a program monitors Cherry Lake, and a recent-rainfall overlay, all refreshed daily. It was last updated August 20, 2026.

Before you swim: the basics

Swim spots near Cherry Lake

All California →

All 6 monitored waters nearest Cherry Lake are clear today.

WaterDistanceTodayAlgae readSampled
Lake EleanorLake · Tuolumne County2.8 miNo advisoryNone detectedAug 19
Hetch Hetchy ReservoirReservoir · Tuolumne County10 miNo advisoryNone detectedAug 19
Pinecrest LakeLake · Tuolumne County14 miNo advisoryNone detectedAug 19
Beardsley LakeLake · Tuolumne County17 miNo advisoryNone detectedAug 19
Donnell LakeLake · Tuolumne County23 miNo advisoryNone detectedAug 19
Spicer Meadow ReservoirReservoir · Alpine County28 miNo advisoryNone detectedAug 19