Reservoir · Morgan County · CO
Is Bijou Number 2 Reservoir safe to swim?
Blue-green algae is above the safe-contact threshold.
Updated July 20, 2026 · EPA CyAN satellite
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What's in the water at Bijou Number 2 Reservoir right now
As of July 20, 2026, Bijou Number 2 Reservoir in Morgan County, Colorado is not recommended for swimming. Satellite imagery measured 2,814,900 cells/mL of blue-green algae on July 19, 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.
Blue-green algae at Bijou Number 2 Reservoir
Bijou Number 2 Reservoir is a reservoir in Morgan County, Colorado. Satellite imagery measured 2,814,900 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.
Bloom history at Bijou Number 2 Reservoir
From EPA CyAN's satellite archive
Over 7 summers of satellite monitoring since 2020, Bijou Number 2 Reservoir has reached blue-green algae advisory levels in 5 of them, most recently in June 2026. This is a lake that blooms most summers. Its highest recorded reading was 4,187,386 cells/mL in July 2022.
Frequently asked: swimming in Bijou Number 2 Reservoir
- Is it safe to swim in Bijou Number 2 Reservoir right now?
- Bijou Number 2 Reservoir is not recommended for swimming today. Satellite imagery measured 2,814,900 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 Bijou Number 2 Reservoir have blue-green algae (cyanobacteria)?
- Yes. Satellite monitoring measured 2,814,900 cells/mL of blue-green algae (cyanobacteria) at Bijou Number 2 Reservoir 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 Bijou Number 2 Reservoir?
- No. Blue-green algae at Bijou Number 2 Reservoir is above the safe-contact threshold (2,814,900 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 Bijou Number 2 Reservoir have blue-green algae blooms?
- Over 7 summers of satellite monitoring since 2020, Bijou Number 2 Reservoir has reached blue-green algae advisory levels in 5 of them, most recently in June 2026. This is a lake that blooms most summers. Its highest recorded reading was 4,187,386 cells/mL in July 2022.
- How many Colorado lakes and beaches are unsafe for swimming today?
- Today, 26 Colorado waters are above a safe-contact threshold and 3 more warrant caution, out of 113 monitored waters SwimZone tracks in the state.
- How is Bijou Number 2 Reservoir'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 Bijou Number 2 Reservoir, and a recent-rainfall overlay, all refreshed daily. It was last updated July 20, 2026.