When cyanobacteria (blue-green algae) reproduce quickly and bloom, there are physical signs. The blooms can look like blue or green paint spilled into the water, a blue or green colored crust along the shoreline, thick puffy blue or green foams on the surface of the water (scums), or swirling colors beneath the surface of the water. Blooms can sometimes be white, brown, or red in color. Cyanobacteria blooms can also have distinct smells. They can smell grassy or septic, and in some cases the smell can cause nausea. These cyanobacteria blooms can accumulate near the shoreline and can move based on wind and wave action. Long strands of green algae, duckweed, and filamentous macro-algae are sometimes confused with cyanobacteria blooms. Please visit the gallery below to see some of the different forms cyanobacteria blooms can take and some commonly confused plants that could look like a bloom.

Cyanobacteria Bloom- Green Water

 Browns 2019.jpgBrowns Lake 2019 algae.jpgCopy VERNOR LAKE BLOOM PIC_7-9-19.jpg Carlton 2018.JPGCatherine 2017.jpgCentralia 2019 (4).jpg Illinois River 2021.jpgSwan 2017 (2).jpgParadise 2017.jpg Centralia 2020.jpgLe Aqua Na 2016.JPG


Cyanobacteria Bloom - Spilled Paint

  2012 Blue-Green Algae Bloom Silver 2015.JPGLong Lake 2015 (2).JPG Illinois River Ottawa 2018.JPGWest Franfort New 2013 IMG_20130716_090620_039.jpg  


Cyanobacteria Bloom - Scum

  2012 Blue-Green Algae Bloom Deer Lake in Goodfield 2016.JPGKa-Ho Mt. Olive 2013 SAM_0287.jpg   Centralia 2019  (2).jpgCountryside 2015.jpgDunlap 2018.jpg   Ka-Ho Mt. Olive 2013 SAM_0295.jpg  


Cyanobacteria Bloom - Globules

 Carbondale City 2019.jpgHighlandCove3_4 2013.JPGW.F. New spillway2_10-3-13.jpg


Not a Cyanobacteria Bloom

  Duck Week is Commonly Mistaken for Blue-Green Algae labeled duckweed pic4_june 2021.jpglabeled IMG_0049.jpg labeled IMG_0078.jpglabeled IMG_0080.jpgLabled Duck Weed 20210526_110104.jpglabled filamentous algae4_June 2021.jpglabled IMG_0051.jpglabled IMG_0063.jpgfilamentous algae2_June 2021.jpg