The slow death of the Olifants River in Mpumalanga is endangering fish, crocodiles and one of South Africa’s most important commercial farming regions, Groblersdal.
Farmers in the area produce fruit, vegetables, maize, wheat and cotton worth an estimated R150-million a year, of which between R50-million and R100-million is sold to the European Union.
But EuroGAP, the quality regulator for all agricultural imports to the EU, has repeatedly warned farmers to attend to the deteriorating quality of water in the Loskop Dam, which is fed by the Olifants River, or risk losing export deals.
‘The Olifants River is definitely in [the] ICU,” said Paul Oberholster, a researcher at the Council for Scientific and Industrial Research (CSIR). A CSIR team is finalising a study about the alarming condition of the upper Olifants and, although Oberholster’s research unit is devising a plan to rehabilitate the threatened river, he estimates it may take decades.
Years of raw sewage flowing into the river, irresponsible mining, industrial pollution and agricultural fertilisers seeping into the Olifants have made it toxic.
On a recent trip the Mail & Guardian watched CSIR scientists test an Olifants River tributary, the Klipspruit, near the Ferrobank industrial zone. An acid stench hung in the air and the rocks in the riverbed have been eaten away.
CSIR scientist James Dabrowski found heavy metals, salts and aluminium in the stream. At another site, Riverview, in Witbank, raw sewage from the local water treatment site has left a white residue where it flows into the river. But fisherman were casting their lines next to the outflow.
Riverview recently received a damning 14.5% rating in the government’s Green Drop report, which particularly censured the quality of water it releases.
All the sites tested along the river revealed mild to heavy microbial contamination, most likely as a result of untreated or poorly treated sewage, according to CSIR microbiologist Martella du Preez. She warned that it posed health hazards to communities living along the river.
The Olifants River Forum asked the CSIR last year to investigate the river’s worsening condition. The forum’s chairperson, Vik Cogho, said the aim was not to point fingers but to work with farmers, mines, industry and local councils to find solutions.
Groblersdal farmers are alarmed by the deteriorating state of the water in the Loskop Dam, which feeds 700km of irrigation canals below it. A vegetable farmer, who asked not to be identified for fear of losing contracts, said: ‘We would do anything to get the water improved. When the water quality is bad, it affects the health risk from the vegetables we’re producing. If the dam dies, we die.”
A series of crocodile deaths in the Kruger National Park in 2008, following several high-profile fish deaths, set off alarm bells. Scientists have since linked it to pansteatitis, a disease caused by the depletion of antioxidants, which causes paralysis in animals. It is estimated more than 160 crocodiles died along the Olifants between May and August 2008.
The CSIR scientists have now found pansteatitis in yellowfish in the upper catchment area of the Olifants. Loskop Dam ranger Jannie Coetzee said he was growing more worried by the day.
A decade ago he would see several crocodiles basking in the sun during his daily rounds — now he was lucky if he spotted one, he said. He also pointed out blooms of a toxic blue-green algae — cyanobacteria — in the dam.
It has also been linked to deaths in a number of species. From the Loskop Dam, the Olifants flows to the Flag Boshielo Dam, through the Kruger Park and into the Massinger Dam in Mozambique.
Water quality woes imperil Kimberley’s flamingos
South Africa’s sewage crisis could torpedo one of the three local breeding sites of the country’s ‘bird of the year” — the lesser flamingo. Kimberley’s Kamfers Dam has seen thousands of flamingo chicks hatch on its islands in recent years, but the state of the dam may halt the large-scale breeding programme.
Last week the water affairs department released its Green Drop report, showing that South Africa’s water treatment plants are collapsing because of lack of maintenance, especially in smaller towns.
The Homevale treatment plant, next to Kamfers Dam, was among the plants that failed to cooperate with the report. The department has ordered a strict audit of the facility.
The Save the Flamingo Association said that deteriorating water quality and rising water levels are making the Kamfers Dam increasingly unsuitable for lesser flamingos.
‘This is a disaster,” said Jahn Hohne, the association’s chairperson. ‘Kimberley is about to lose one of its most important assets and tourist attractions.”
Hohne said although some work is being done at the Homevale waste water treatment plant, no progress has been made in upgrading the sewerage works.
‘More than R200- million is required to upgrade the works so that it can process Kimberley’s waste water and treat it to an acceptable standard, money that the Sol Plaatje municipality does not have,” he said.
A recent study by Jan Roos of Water Quality Consultants in Bloemfontein showed that the dam’s aquatic system was under severe pressure because of a massive cyanobacterial (algal) bloom and extreme oscillations in oxygen concentration, driven by poor water quality.
According to Roos, levels of nitrogen, ammonium, fluoride and phosphates in the inflowing sewage water are exceptionally high. The sewerage works’ non-compliance with treatment standards remains ‘the biggest problem”, he said in his report.
Water levels at the dam are now at their highest on record, leaving more than two-thirds of the flamingo breeding island flooded and putting two important railway lines at risk.
‘Kamfers Dam is one of the most important feeding sites for lesser flamingos in Southern Africa, but this may change,” said Mark Anderson, an expert on the biology and conservation of bird species.
‘The composition of algae is changing from mainly the bluegreen algae, Spirulina platensis, which is the dominant food of the lesser flamingos, to Chlorella, one of the green algae [types].”
There is concern that toxin-producing algae such as Microcystis may soon appear in the polluted wetland. These are thought to be responsible for the mass death of lesser flamingos on lakes in East Africa.