Is Pleasant Hill Lake safe to swim?

As of July 22, 2026, Pleasant Hill Lake in Richland County, Ohio is clear to swim. Satellite imagery detected no blue-green algae bloom as of July 19, 2026. Rainfall over the past week totaled 0.5 in, which can wash bacteria and nutrients into the water.

How this read is built

Pleasant Hill Lake is a lake in Richland County, Ohio covering about 1.2 sq mi, the 24th-largest of the 41 lakes SwimZone monitors in Ohio. Satellite imagery detected no blue-green algae bloom as of July 19, 2026.

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.

Over 7 summers of satellite monitoring since 2020, Pleasant Hill Lake has reached blue-green algae advisory levels in 3 of them, most recently in July 2026. Its highest recorded reading was 1,308,648 cells/mL in September 2021.

Is it safe to swim in Pleasant Hill Lake right now?

Pleasant Hill Lake is clear to swim today. Satellite imagery detected no blue-green algae bloom as of July 19, 2026. Conditions can change quickly with wind, heat, and rain, so check the posted signs and look at the water before you get in.

Does Pleasant Hill Lake have blue-green algae (cyanobacteria)?

No blue-green algae bloom is detectable at Pleasant Hill Lake as of July 19, 2026 (below the satellite's roughly 10,000 cells/mL detection limit). Cyanobacteria can still appear within hours in warm, calm, nutrient-rich water, so look before you swim.

Can dogs swim in Pleasant Hill Lake?

No bloom is detected at Pleasant Hill 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 Pleasant Hill Lake have blue-green algae blooms?

Over 7 summers of satellite monitoring since 2020, Pleasant Hill Lake has reached blue-green algae advisory levels in 3 of them, most recently in July 2026. Its highest recorded reading was 1,308,648 cells/mL in September 2021.

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 Pleasant Hill 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 Pleasant Hill Lake, and a recent-rainfall overlay, all refreshed daily. It was last updated July 22, 2026.