Is Lake Tom-A-Lex safe to swim?

As of July 20, 2026, Lake Tom-A-Lex in Davidson County, North Carolina is not recommended for swimming. Satellite imagery measured 807,947 cells/mL of blue-green algae on July 19, 2026, above the 100,000 cells/mL advisory threshold. Rainfall over the past week totaled 2.8 in, which can wash bacteria and nutrients into the water.

How this read is built

Lake Tom-A-Lex is a lake in Davidson County, North Carolina covering about 0.9 sq mi, the 37th-largest of the 44 lakes SwimZone monitors in North Carolina. Satellite imagery measured 807,947 cells/mL of blue-green algae on July 19, 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.

Over 7 summers of satellite monitoring since 2020, Lake Tom-A-Lex has reached blue-green algae advisory levels in 3 of them, most recently in September 2023. Its highest recorded reading was 742,033 cells/mL in September 2023.

Is it safe to swim in Lake Tom-A-Lex right now?

Lake Tom-A-Lex is not recommended for swimming today. Satellite imagery measured 807,947 cells/mL of blue-green algae on July 19, 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 Lake Tom-A-Lex have blue-green algae (cyanobacteria)?

Yes. Satellite monitoring measured 807,947 cells/mL of blue-green algae (cyanobacteria) at Lake Tom-A-Lex on July 19, 2026, above the 100,000 cells/mL advisory level. Avoid swimming and keep children and pets out of the water.

Can dogs swim in Lake Tom-A-Lex?

No. Blue-green algae at Lake Tom-A-Lex is above the safe-contact threshold (807,947 cells/mL on July 19, 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 Lake Tom-A-Lex have blue-green algae blooms?

Over 7 summers of satellite monitoring since 2020, Lake Tom-A-Lex has reached blue-green algae advisory levels in 3 of them, most recently in September 2023. Its highest recorded reading was 742,033 cells/mL in September 2023.

How many North Carolina lakes and beaches are unsafe for swimming today?

Today, 13 North Carolina waters are above a safe-contact threshold and 96 more warrant caution, out of 255 monitored waters SwimZone tracks in the state.

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