The clock is ticking for South Africa’s stretched water supply, and in another five years demand will have caught up with supply, according to a top official.
Jones Mnisi, acting chief operating officer at Johannesburg Water, the public utility overseeing supply in the country’s economic hub, told a recent conference on water security that the tipping point where demand outstripped supply may not be far away.
South Africa is chronically waterstressed. Although growth has slowed, an expanding economy, a growing population, and increased evaporation caused by climate change are conspiring to put additional pressures on water resources.
Yet leading experts at the conference said the situation could be addressed if the country curbed demand and improved water quality to facilitate reuse. A paper by the World Wide Fund for Nature (WWF) said South Africa’s water surplus had been dangerously low since at least 2000 - four years after the country began buying bulk water from the multi-dam Lesotho Highlands Water Project, built on the Senqunyane River in neighbouring Lesotho.
Although the next phase of the project, expected to be in place in 2019, could relieve some of the pressure on South Africa’s water supply, it was likely to be too late, said Chris Herold, chairman of the water division of the South African Institute of Civil Engineering (SAICE).
Quantity and qualityExperts said the quality and quantity of the water supply should be better managed, and called for more investment in infrastructure. “The national water resource strategy has assumed that water demand management will happen,” said Herold, “On the implementation side, some of the local authorities have not come to the party.
” Anthony Turton, a former researcher at the Council for Scientific and Industrial Research, who now works as a water management consultant, predicted that South Africa would soon have to start reusing effluent, which would entail revamping infrastructure, with waste treatment plants a priority.
Water treatment plants would have to produce effluent clean enough for reuse in the industrial sector, for example switching to buying cheaper, recycled water for cooling plants, he said.
This may be harder than it sounds. Turton pointed out that 12 wastewater treatment plants, none of which function properly, were dumping effluent into the Hartbeespoort Dam on the Crocodile River, 20km southwest of Johannesburg. He and others have also begun to conclude that if water could be stored in underground man-made aquifers, he said, it could save a vast quantity of water from evaporation annually.
When the democratic government came to power in 1994, an estimated 14 million people lacked access to a formal water supply, and about half the population had no formal sanitation, according to the Department of Water and Environment.
Water and sanitation remain contentious issues, and government has assured South Africans that it will commit more funds to improve water infrastructure, deploy personnel to local government to oversee operations, build capacity, and ensure proper financial management.
A recent progress report card on the UN Millennium Development Goals said the country was on track for achieving access to safe drinking water and sanitation by 2015. “Water service provision is critical, and it is a sensitive issue,” Turton said. “We have to give people everything that the struggle was about, like dignity. If we don’t, we’re going to have a lot of angry people.”
SAICE’s Herold said government should crack down on hundreds of farmers who used water illegally from the Vaal River, 100km south of Johannesburg, which supplies the city. The department of water affairs has established a unit, known as the “Blue Scorpions”, to police illegal bulk water use.
Dam Facts and FiguresAccording to the World Commission on Dams there are an estimated 48 000 dams worldwide over 15 m high. About half of these are in China.
There are about 1 500 dams under construction worldwide at present.
It takes about four years to build one dam.
The highest dam in the world is the Rogun Dam in Tajikistan which is 335 m high.
The Three Gorges Dam, which is being built in China, will be the largest concrete dam in the world. When it is completed in 2009, the dam will stretch almost two kilometres across the Yangtze River and soar 183 m above the valley floor. The reservoir will be 563 km long.