Is Upper Pahranagat Lake safe to swim?

As of July 20, 2026, Upper Pahranagat Lake in Lincoln County, Nevada is clear to swim. Satellite imagery detected no blue-green algae bloom as of July 19, 2026. Rainfall over the past week totaled 0.3 in, which can wash bacteria and nutrients into the water.

How this read is built

Upper Pahranagat Lake is a lake in Lincoln County, Nevada covering about 0.7 sq mi, the 33rd-largest of the 47 lakes SwimZone monitors in Nevada. Satellite imagery detected no blue-green algae bloom as of July 19, 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, Upper Pahranagat Lake has reached blue-green algae advisory levels in 2 of them, most recently in September 2022. Blooms here have been occasional rather than annual. Its highest recorded reading was 3,633,649 cells/mL in September 2020.

Is it safe to swim in Upper Pahranagat Lake right now?

Upper Pahranagat Lake is clear to swim today. Satellite imagery detected no blue-green algae bloom as of July 19, 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 Upper Pahranagat Lake have blue-green algae (cyanobacteria)?

No blue-green algae bloom is detectable at Upper Pahranagat Lake as of July 19, 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 Upper Pahranagat Lake?

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

Over 7 summers of satellite monitoring since 2020, Upper Pahranagat Lake has reached blue-green algae advisory levels in 2 of them, most recently in September 2022. Blooms here have been occasional rather than annual. Its highest recorded reading was 3,633,649 cells/mL in September 2020.

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

Today, 13 Nevada waters are above a safe-contact threshold and 1 more warrant caution, out of 50 monitored waters SwimZone tracks in the state.

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