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A summer 2019 blue-green algae bloom along a cove near Old Church Road at Blue Marsh Lake in Penn Township. U.S. Army Corps of Engineers ecologist Gregory Wacik says harmful algal blooms, which generally occur each summer, often look like a paint slick on the water.
U.S. Army Corps of Engineers
A harmful algal bloom as seen along a Blue Marsh Lake beach in 2019. The blooms generally occur each summer. Humans and pets should avoid coming in contact with water that looks like this to avoid getting ill from bacteria the algae harbors.
U.S. Army Corps of Engineers
Phoenixville
Pennsylvania
United-states
Montgomery-county
Philadelphia
Blue-marsh-lake
Bern
Switzerland
Pottstown
America
American
Donnap-alston