Is Normandy Lake safe to swim?

As of July 20, 2026, Normandy Lake in Coffee County, Tennessee is clear to swim. Satellite imagery detected no blue-green algae bloom as of July 18, 2026. Rainfall over the past week totaled 6.8 in, which can wash bacteria and nutrients into the water.

How this read is built

Normandy Lake is a lake in Coffee County, Tennessee covering about 4.9 sq mi, the 13th-largest of the 20 lakes SwimZone monitors in Tennessee. Satellite imagery detected no blue-green algae bloom as of July 18, 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, Normandy Lake has reached blue-green algae advisory levels in 2 of them, most recently in September 2023. Blooms here have been occasional rather than annual. Its highest recorded reading was 174,624 cells/mL in May 2020.

Is it safe to swim in Normandy Lake right now?

Normandy Lake is clear to swim today. Satellite imagery detected no blue-green algae bloom as of July 18, 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 Normandy Lake have blue-green algae (cyanobacteria)?

No blue-green algae bloom is detectable at Normandy Lake as of July 18, 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 Normandy Lake?

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

Over 7 summers of satellite monitoring since 2020, Normandy Lake has reached blue-green algae advisory levels in 2 of them, most recently in September 2023. Blooms here have been occasional rather than annual. Its highest recorded reading was 174,624 cells/mL in May 2020.

How many Tennessee lakes and beaches are unsafe for swimming today?

Today, 4 Tennessee waters are above a safe-contact threshold and 0 more warrant caution, out of 24 monitored waters SwimZone tracks in the state.

How is Normandy 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 Normandy Lake, and a recent-rainfall overlay, all refreshed daily. It was last updated July 20, 2026.