Lake · Ross County · OH

Is Paint Creek Lake safe to swim?

Advisory

Blue-green algae is above the safe-contact threshold.

Updated July 22, 2026 · EPA CyAN satellite

Recent rain
0.2 in
Water type
Lake
Last updated
Jul 22
Bacteria
E. coli, fecal
Not monitored
Tested
Not monitored

No bacteria advisory or sampling for this water.

Blue-green algae
cyanobacteria
Advisory
Tested
445,311
cells/mL
Advisory over
100,000
cells/mL

Cyanobacteria 445,311 cells/mL (satellite, 7-day max), imaged 2026-07-21.

Sampled Jul 21 · EPA CyAN satellite

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There's an advisory on Paint Creek Lake right now.

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What's in the water at Paint Creek Lake right now

As of July 22, 2026, Paint Creek Lake in Ross County, Ohio is not recommended for swimming. Satellite imagery measured 445,311 cells/mL of blue-green algae on July 21, 2026, above the 100,000 cells/mL advisory threshold. Rainfall over the past week totaled 0.2 in, which can wash bacteria and nutrients into the water.

How this read is built

Blue-green algae at Paint Creek Lake

Paint Creek Lake is a lake in Ross County, Ohio covering about 1.8 sq mi, the 20th-largest of the 41 lakes SwimZone monitors in Ohio. Satellite imagery measured 445,311 cells/mL of blue-green algae on July 21, 2026, above the 100,000 cells/mL advisory threshold.

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 Paint Creek Lake

From EPA CyAN's satellite archive

2020: peak 785,350 cells/mL — above the 100,000 advisory level20212022: peak 1,272,047 cells/mL — above the 100,000 advisory level222023: peak 1,508,075 cells/mL — above the 100,000 advisory level232024: peak 763,384 cells/mL — above the 100,000 advisory level24252026: peak 625,897 cells/mL — above the 100,000 advisory level26Advisory100k cells/mL

Each bar is that summer's peak satellite reading (log scale). The red cap is the part above the advisory level.

Over 7 summers of satellite monitoring since 2020, Paint Creek Lake has reached blue-green algae advisory levels in 5 of them, most recently in July 2026. This is a lake that blooms most summers. Its highest recorded reading was 1,508,075 cells/mL in August 2023.

When to swim at Paint Creek Lake

It is currently peak season for blue-green algae, when warm, calm water lets blooms form fastest. This lake has bloomed in most monitored summers (5 of 7), historically peaking around August. Early summer, before the water fully warms, has generally been the safer window here; check the current read before you go either way.

Frequently asked: swimming in Paint Creek Lake

Is it safe to swim in Paint Creek Lake right now?
Paint Creek Lake is not recommended for swimming today. Satellite imagery measured 445,311 cells/mL of blue-green algae on July 21, 2026, above the 100,000 cells/mL advisory threshold. Conditions can change quickly with wind, heat, and rain, so check the posted signs and look at the water before you get in.
Does Paint Creek Lake have blue-green algae (cyanobacteria)?
Yes. Satellite monitoring measured 445,311 cells/mL of blue-green algae (cyanobacteria) at Paint Creek Lake on July 21, 2026, above the 100,000 cells/mL advisory level. Avoid swimming and keep children and pets out of the water.
Can dogs swim in Paint Creek Lake?
No. Blue-green algae at Paint Creek Lake is above the safe-contact threshold (445,311 cells/mL on July 21, 2026). Cyanobacteria toxins can be rapidly fatal to dogs, which swallow it while swimming and lick it from their fur. Keep dogs out of the water and away from any scum along the shore.
How often does Paint Creek Lake have blue-green algae blooms?
Over 7 summers of satellite monitoring since 2020, Paint Creek Lake has reached blue-green algae advisory levels in 5 of them, most recently in July 2026. This is a lake that blooms most summers. Its highest recorded reading was 1,508,075 cells/mL in August 2023.
How many Ohio lakes and beaches are unsafe for swimming today?
Today, 33 Ohio waters are above a safe-contact threshold and 32 more warrant caution, out of 101 monitored waters SwimZone tracks in the state.
How is Paint Creek 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 Paint Creek Lake, and a recent-rainfall overlay, all refreshed daily. It was last updated July 22, 2026.

Before you swim: the basics

Swim spots near Paint Creek Lake

All Ohio

Of the 6 monitored waters nearest Paint Creek Lake, 4 are flagged today.

WaterDistanceTodayAlgae readSampled
Rocky Fork LakeLake · Highland County7.3 miAdvisory307,966 cells/mLJul 21
Deer Creek LakeLake · Pickaway County26 miAdvisory662,435 cells/mLJul 21
Cowan LakeLake · Clinton County29 miClear to swimNone detectedJul 21
William H Harsha LakeLake · Clermont County43 miAdvisory160,377 cells/mLJul 21
Lake ChoctawLake · Madison County49 miAdvisory1,465,895 cells/mLJul 21
Clarence J Brown ReservoirReservoir · Clark County52 miClear to swimNone detectedJul 21