Now you can click on a dam to see if it's safe to swim

20 September 2017 - 14:02
By Claire Keeton
Cyanobacteria. File photo.
Image: Gallo Images/ IStock Cyanobacteria. File photo.

To find out how clean or polluted your nearest dam is‚ click on an interactive map which reports on 105 dams in South Africa.

The online tool‚ which relies on satellite information‚ was launched this week at a symposium in Johannesburg hosted by the Water Research Council‚ which funded its development by the organisation CyanoLakes.

CyanoLakes founder Mark Matthews said: “We want to empower the public to make information decisions about their safety and the risks present in dams.”

On Wednesday‚ 63% of monitored dams were safe for full-contact water sports such as swimming‚ while 67% were safe for partial contact sports like fishing.

Cyanolakes' map.
Image: Supplied Cyanolakes' map.

The data clearly shows health risks (high‚ moderate‚ mild and low) and nutrient pollution (from very high to low). The Earth Observation National Eurotrophic Monitoring Programme site also lists a cell count for cyanobacteria — algae-like organisms called blue-greens‚ some of which produce toxins dangerous to humans.

Roughly a sixth of the dams had a “red” health risk on Wednesday from either high nutrient levels or cyanobacteria.

Matthews said: “We hope to be saving lives by reducing the negative consequences of waterborne diseases and cynobacteria. We also aim to enhance the ability of national government to handle nutrification and fill in the gaps in information.”

At the three-day symposium a number of innovations which could be invaluable in saving water were demonstrated.

Said Matthews: “We need to get behind our own innovators who have technologies using a fraction of the water consumed by the old-school technologies which we are importing.”

Other water-saving devices identified problems with water consumption which could be fixed. “For example‚ Stellenbosch University presented a device monitoring water consumption which they installed at four or five schools.

“They noticed huge amounts of water were being used when students were not there. As a result one school then spent about R10 000 on maintenance and reduced their water bill by about R30 000 to R40 000 a month.”

Sputnik Ratau‚ spokesman for the Department of Water and Sanitation‚ said it was useful to bring together researchers and innovators. “This sharing of experience‚ expertise and knowledge will enrich research institutions and ultimately address some of the water challenges in South Africa‚” he said.

The Western Cape and Eastern Cape are experiencing severe water shortages because of drought and the demands of increasing populations.

South Africa’s average annual rainfall of 490mm is far lower than the global average of 814mm‚ according to the World Wide Fund For Nature.