Blue-Green algae in water no cause for alarm, says DA

30/01/2025News

The DA in Gauteng said that residents need not be alarmed by reports circulating on social media regarding cyanobacteria or blue-green algae in the Hennops River and Hartbeespoort Dam, among other water bodies.

“Following rigorous engagement with experts on the subject matter, the Democratic Alliance (DA) in Gauteng can confirm that cyanobacteria is a natural component of river ecosystems and does not inherently pose the risks suggested in recent social media posts,” said Leanne De Jager MPL – DA Gauteng Spokesperson for Environmental Affairs. “The presence of cyanobacteria in our waterways is a natural occurrence and part of healthy aquatic ecosystems. These photosynthetic bacteria play crucial roles in oxygen production, nitrogen fixation and creating beneficial relationships with aquatic plants. While we understand public concern about water quality, the recent characterisation of cyanobacteria as a severe threat has been unnecessarily alarmist. The DA will continue to monitor water quality throughout Gauteng’s water systems, ensuring public safety remains our top priority.” She said residents should rely on official communications regarding water quality rather than unverified social media reports. John Wesson of WESSA welcomed the statement. “There has been a lot of discussion around Cyanobacteria with inaccurate facts causing fear. Cyanobacteria, often called blue-green algae, are a group of bacteria that can photosynthesise, which means they use sunlight to produce food and oxygen. These microorganisms are incredibly ancient and are thought to have played a significant role in shaping Earth’s early atmosphere, leading to the presence of oxygen which is essential for many forms of life. Cyanobacteria can be found in various environments, including freshwater, saltwater, and even on land. They are important for the ecosystem as they contribute to nutrient cycling and nitrogen fixation. However, under certain conditions, such as nutrient pollution and warm temperatures, they can form harmful algal blooms that produce toxins harmful to aquatic life, animals, and humans.”