Harmful Algal Bloom (HAB)

Blue-Green Algae Heading

To Report an Algal Bloom use the
report form on the menu or call



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What are blue-green algae?

Blue-green algae can be considered as simple aquatic plants that exist naturally in marine waters, rivers, lakes, and ponds. Despite their name, blue-green algae are actually types of bacteria known as Cyanobacteria. When certain conditions are present, such as high nutrient and light levels, these organisms can reproduce rapidly. This dense growth of algae is called a bloom. Some of these blooms are harmless, but when the blooming organisms contain toxins, other noxious chemicals, pathogens, or other impacts to recreation or economic activities, it is known as a harmful algal bloom.

What does a typical blue-green

algae bloom look like?

Some algae blooms can look like foam, or a thick slurry. The blooms can be blue, bright green, brown, or red and may look like paint floating on the water. Some blooms may not affect the appearance of the water.

Why should I be aware of

blue-green algae?

Some blue-green algae produce toxins that could pose a health risk to people and animals when they are exposed to them in large enough quantities, yet the mere presence of blue-green algae is not a cause for alarm. Health effects could occur when surface scums or water containing high levels of blue-green algal toxins are swallowed, through contact with the skin or when airborne droplets containing toxins are inhaled while swimming, boating, and skiing. A large percentage of the public will report "allergic" type reactions after exposure to blue-green algae, such as intestinal problems, respiratory problems, or skin irritations. Harmful Algae Blooms can appear (or disappear) rapidly. Always be mindful of any unusual look to the lake including a green or brown color, scum, or paint-like appearance and if you see what might be a bloom, please let the lake manager or other lake official know of your concerns and complete the observation form below.

What should I do if I see

a bloom?

Complete the Algal Bloom Report Form or contact us by email at HarmfulAlgae@kdheks.gov.


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