NATIONAL PARK SERVICE · news
Toxic Algae detected in Blue Mesa Reservoir
August 13, 2026 · Source: National Park Service
Throughout the summer, National Park Service staff sample and analyze the Blue Mesa Reservoir water for the presence of blue-green algae containing cyanotoxins. At this time, toxic algae have been detected at low levels in the Iola Basin. These levels are under the State of Colorado toxicity threshold. The Iola Basin has been posted with yellow caution signs—consistent with State of Colorado and U.S. Environmental Protection Agency guidance.
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Traveler guidance by State & Nation Staff Writer.