Is Alkali Lake safe to swim?

As of July 20, 2026, Alkali Lake in Kidder County, North Dakota is clear to swim. Satellite imagery measured 8,633 cells/mL of blue-green algae on July 19, 2026, well below the 100,000 cells/mL advisory threshold. Rainfall over the past week totaled 0.0 in, which can wash bacteria and nutrients into the water.

How this read is built

Alkali Lake is a lake in Kidder County, North Dakota covering about 3.7 sq mi, the 24th-largest of the 216 lakes SwimZone monitors in North Dakota. Satellite imagery measured 8,633 cells/mL of blue-green algae on July 19, 2026, well below 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, Alkali Lake has reached blue-green algae advisory levels in 6 of them, most recently in July 2025. This is a lake that blooms most summers. Its highest recorded reading was 2,002,733 cells/mL in July 2025.

Is it safe to swim in Alkali Lake right now?

Alkali Lake is clear to swim today. Satellite imagery measured 8,633 cells/mL of blue-green algae on July 19, 2026, well below 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 Alkali Lake have blue-green algae (cyanobacteria)?

Low levels. Satellite monitoring measured 8,633 cells/mL at Alkali Lake on July 19, 2026, below the 100,000 cells/mL advisory threshold. Keep an eye out for surface scum, which can concentrate quickly.

Can dogs swim in Alkali Lake?

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

Over 7 summers of satellite monitoring since 2020, Alkali Lake has reached blue-green algae advisory levels in 6 of them, most recently in July 2025. This is a lake that blooms most summers. Its highest recorded reading was 2,002,733 cells/mL in July 2025.

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

Today, 167 North Dakota waters are above a safe-contact threshold and 4 more warrant caution, out of 241 monitored waters SwimZone tracks in the state.

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