Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 22 April 2010
Recent water samples taken of the Westlake River have confirmed the presence of blue-green algae, as well as the presence of the toxins associated with it.
Due to its potential health risks, Dr Ivan Bromfield, Executive Director: City Health, would like to warn the general public of the Kirstenhof area, as well as recreational users who frequent the public open space along Westlake River, to exercise caution and avoid contact with the visible algae blooms until further notice.
This type of algae does not generally occur in flowing rivers. It has been established that a dam upstream has had a blue-green algae outbreak and therefore water flowing over the dam wall into the Westlake River carries with it blue-green algal cells. Investigations are also being undertaken downstream at Zandvlei since this river flows into the vlei. The saline conditions in the vlei should help to cause the algae to die off.
“Blue-green algae and the toxins it releases can present a health hazard for those swimming or playing in the river, especially children and pets. We recommend that people stay out of the water and keep their dogs out of the river as well,” Bromfield said.
The algal blooms look like green, blue-green, white, or brown foam, scum or mats floating on the water. Recreational exposure to toxic blue-green algae can cause eye irritations, allergic skin rashes, mouth ulcers, vomiting, diarrhoea, and cold- and flu-like symptoms. Accidentally swallowing or drinking large amounts of contaminated water can be extremely dangerous. Should any person for any reason come into direct contact with the blue-green algae they should wash themselves immediately with clean water. If any symptoms are evident, they should immediately seek medical advice.
With proper precautions to avoid water contact, people can still use the public open space along Westlake River and enjoy activities that exclude any direct contact with the algae bloom or scum, such as biking and picnicking.
Warning signs informing the public of the presence of blue-green algae and its risks have been placed along Westlake River. As part of the City of Cape Town’s water quality monitoring programme regular water samples are taken in order to assess and evaluate the status of Westlake River and once the potential health risk has abated the warning signs will be removed.
Should any person require any further information the Wynberg Environmental Health Office can be contacted on 021 762 1202/5.