Is Big Hill Lake safe to swim?

As of July 20, 2026, Big Hill Lake in Labette County, Kansas is not recommended for swimming. Satellite imagery measured 458,124 cells/mL of blue-green algae on July 18, 2026, above 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

Big Hill Lake is a lake in Labette County, Kansas covering about 1.7 sq mi, the 20th-largest of the 28 lakes SwimZone monitors in Kansas. Satellite imagery measured 458,124 cells/mL of blue-green algae on July 18, 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, Big Hill Lake has reached blue-green algae advisory levels in 7 of them, most recently in July 2026. This is a lake that blooms most summers. Its highest recorded reading was 543,129 cells/mL in July 2026.

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

Big Hill Lake is not recommended for swimming today. Satellite imagery measured 458,124 cells/mL of blue-green algae on July 18, 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 Big Hill Lake have blue-green algae (cyanobacteria)?

Yes. Satellite monitoring measured 458,124 cells/mL of blue-green algae (cyanobacteria) at Big Hill Lake on July 18, 2026, above the 100,000 cells/mL advisory level. Avoid swimming and keep children and pets out of the water.

Can dogs swim in Big Hill Lake?

No. Blue-green algae at Big Hill Lake is above the safe-contact threshold (458,124 cells/mL on July 18, 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 Big Hill Lake have blue-green algae blooms?

Over 7 summers of satellite monitoring since 2020, Big Hill Lake has reached blue-green algae advisory levels in 7 of them, most recently in July 2026. This is a lake that blooms most summers. Its highest recorded reading was 543,129 cells/mL in July 2026.

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

Today, 10 Kansas waters are above a safe-contact threshold and 1 more warrant caution, out of 30 monitored waters SwimZone tracks in the state.

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