South Portland Parks and Recreation said it found signs of a toxic blue-green algae bloom in Hinckley Park on Monday. Credit: CBS 13

For the third year in a row, South Portland Parks and Recreation said it found a toxic blue-green algae bloom in Hinckley Park.

Blue-green algae is a type of photosynthesizing bacteria called cyanobacteria. It exists in all Maine lakes but is harmless in low concentrations.

However, when the population of this bacteria explodes during an algal bloom, it can produce toxins, according to Scott Williams, executive director of the Lake Stewards of Maine. When ingested, it can kill dogs and harm humans.

When the water is safe, which is expected to be in the fall, the department said it will remove the posted signs warning of the algae.

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