A bloom of purple algae has appeared at Lake Thoreau. Reston Association is monitoring the bloom of Planktothrix rubescens algae.
In a statement, RA said that the algae likely appeared because heavy rains washed different nutrients and sediment into the lake.
Although the algae are expected to clear up on its own, people and pets should avoid ingesting water from the lake. The algae should disappear on its own as cooler conditions take over.
Blue and green algae that appeared on Lake Audubon disappeared after floating on the lake three years ago.
Photo via RA