Lake · Rio Arriba County · NM
Is Stone Lake safe to swim?
No advisory or algae bloom reported for this water today.
Updated July 20, 2026 · EPA CyAN satellite
SwimZone for iPhone · launching soon
Know before you get in at Stone Lake.
Get an alert the day a bacteria or algae advisory goes up.
What's in the water at Stone Lake right now
As of July 20, 2026, Stone Lake in Rio Arriba County, New Mexico 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.
Blue-green algae at Stone Lake
Stone Lake is a lake in Rio Arriba County, New Mexico covering about 0.7 sq mi, the 17th-largest of the 24 lakes SwimZone monitors in New Mexico. 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.
Bloom history at Stone Lake
From EPA CyAN's satellite archive
Over 7 summers of satellite monitoring since 2020, Stone Lake has reached blue-green algae advisory levels in 5 of them, most recently in September 2024. This is a lake that blooms most summers. Its highest recorded reading was 3,738,204 cells/mL in July 2020.
Frequently asked: swimming in Stone Lake
- Is it safe to swim in Stone Lake right now?
- Stone 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 Stone Lake have blue-green algae (cyanobacteria)?
- No blue-green algae bloom is detectable at Stone 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 Stone Lake?
- No bloom is detected at Stone 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 Stone Lake have blue-green algae blooms?
- Over 7 summers of satellite monitoring since 2020, Stone Lake has reached blue-green algae advisory levels in 5 of them, most recently in September 2024. This is a lake that blooms most summers. Its highest recorded reading was 3,738,204 cells/mL in July 2020.
- How many New Mexico lakes and beaches are unsafe for swimming today?
- Today, 4 New Mexico waters are above a safe-contact threshold and 0 more warrant caution, out of 27 monitored waters SwimZone tracks in the state.
- How is Stone 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 Stone Lake, and a recent-rainfall overlay, all refreshed daily. It was last updated July 20, 2026.