Is Oyster Bay safe to swim?

As of July 19, 2026, Oyster Bay in Baldwin County, Alabama is under a swim advisory. Satellite imagery measured 131,493 cells/mL of blue-green algae on July 19, 2026, above the 100,000 cells/mL advisory threshold. No fecal-bacteria advisory is posted (state beach program). Rainfall over the past week totaled 0.3 in, which can wash bacteria and nutrients into the water.

How this read is built

Oyster Bay is a lake in Baldwin County, Alabama covering about 0.9 sq mi, the 11th-largest of the 17 lakes SwimZone monitors in Alabama. Satellite imagery measured 131,493 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, Oyster Bay has reached blue-green algae advisory levels in 6 of them, most recently in July 2026. This is a lake that blooms most summers. Its highest recorded reading was 365,109 cells/mL in September 2022.

Is it safe to swim in Oyster Bay right now?

Oyster Bay is under a swim advisory today. Satellite imagery measured 131,493 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 Oyster Bay have blue-green algae (cyanobacteria)?

Yes. Satellite monitoring measured 131,493 cells/mL of blue-green algae (cyanobacteria) at Oyster Bay 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 Oyster Bay?

No. Oyster Bay is under a blue-green algae advisory (131,493 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 Oyster Bay have blue-green algae blooms?

Over 7 summers of satellite monitoring since 2020, Oyster Bay has reached blue-green algae advisory levels in 6 of them, most recently in July 2026. This is a lake that blooms most summers. Its highest recorded reading was 365,109 cells/mL in September 2022.

How many Alabama lakes and beaches have swim advisories today?

Today, 4 Alabama waters are under a swim advisory and 1 more warrant caution, out of 45 monitored waters SwimZone tracks in the state.

How is Oyster Bay'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 Oyster Bay, and a recent-rainfall overlay, all refreshed daily. It was last updated July 19, 2026.