CITY OF CAPE TOWN
17 MARCH 2017
MEDIA RELEASE
Rietvlei closed to public due to algae
The City of Cape Town is temporarily closing the Rietvlei Water Area after a blue-green algal bloom was observed in the water on 16 March 2017. Read more below:
The Milnerton Aquatic Club’s 24-hour endurance sailing challenge, which was scheduled to take place at the Rietvlei Water Area tomorrow, 18 March and Sunday, 19 March 2017, has been cancelled as a result.
The City collected and analysed water samples yesterday, 16 March 2017, and again this morning, 17 March 2017, and found that microcystin toxins associated with blue-green algae exceeded the World Health Organisation’s recreational guideline for freshwater water bodies.
The algal blooms usually present as green, blue-green, white or brown foam, scum or mats floating on the surface of the water. Exposure to these algae can cause eye irritation, skin rashes, mouth ulcers, vomiting, diarrhoea, and cold-or flu-like symptoms.
Drinking or swallowing large amounts of water can be extremely dangerous.
Members of the public should avoid all contact with the water at Rietvlei until it has been declared safe.
Due to the ongoing drought and low water levels there are extensive areas of exposed dry shoreline around Rietvlei.
It is suspected that the 5 mm rainfall that was recorded on Wednesday, 15 March 2017, washed accumulated minerals and organic material from decomposing and dead plants along the shoreline into the water at Rietvlei. These minerals and organic materials, combined with high ambient temperatures, could have provided the nutrients for the rapid growth of algae in the water.
The City is monitoring the water quality and will inform members of the public once it is safe for recreational use. The City apologises for any inconvenience caused as a result of the closure of the water area.
The closure only applies to recreational activities in the Rietvlei Water Area, including fishing, but does not prevent anybody from accessing the Table Bay Nature Reserve’s other visitor facilities such as the picnic areas, braai facilities and the bird watching trail. As such, the Table Bay Nature Reserve will still host an open weekend on 18 and 19 March 2017.