South Africa is increasingly looking at seawater to quench coastal thirst {writer: Leon Alberts}

With warnings that South Africa’s available freshwater resources are almost fully utilised and under stress; and that water use was not sustainable at projected growth rates dating back almost 20 years to the early 1990s, large-scale desalination of seawater and treatment of so-called grey water – waste water generated from domestic activities such as laundry and bathing – is becoming a reality.

It is foreseen that within the next two decades, South Africa could be acquiring up to a tenth of its drinking water from the sea.

Water and Environmental Affairs Minister Buyelwa Sonjica said in her Budget speech on 15 April that the water-scarce country would look to use desalinated seawater to meet the growing demand for drinking water.

South Africa increasingly will use desalinated seawater to meet growing demand for drinking water, particularly in coastal towns facing the worst drought in 150 years, she said.

South Africa is a water-scarce country with an average rainfall of 450 millimetres, compared to a world average of 860mm.

Conditions are expected to worsen as a result of global warming.

“South Africa has a boundary consisting of approximately 3 000 kilometres of seawater, and this water is presently unusable because of its high salt content.

“We therefore made a decision to press ahead with unconventional water treatment, in this case desalination, largely because of the unavailability of river water due to drought,” said the minister.

In the meantime, the first seawater desalination plant already has become operational at Sedgefield on the Garden Route. A contract for the construction of the R16-million plant was signed in Knysna by the municipality in October last year and brought some relief during the December 2009 tourist season.

Popular tourist coastal towns of Plettenberg Bay, Knysna, George and Mossel Bay are facing severe water shortages due to prolonged drought in the southern Cape region.

Earlier in 2009, Sedgefield’s reservoir ran dry, forcing the Knysna Municipality to truck in water from George.

At capacity, the Sedgefield plant can produce 1.5 million litres of water per day and is the largest desalination unit in South Africa, but even larger plants are planned for George, Plettenberg Bay and Knysna – all scheduled for completion before the end of the year.

In the interim, the government’s long-awaited rollout of R140 million in drought-relief funding to Garden Route municipalities began in April, bringing the promise of respite to a region struggling to provide water to support its main income earner – the tourist industry.

In the same month, Eden District Municipality disaster management head Gerhard Otto said the money would be spent on desalination and waste-water recycling plants planned for towns along the Garden Route, considered essential to beat the worst drought in living memory.

The drought set in about 18 months ago, and is expected to continue.

Bitou infrastructure development manager Pumla Ngqumshe said while rains from December to February had boosted the major river systems that gave Plettenberg Bay its water, there had been no inflow from the Piesang River to the town’s Roodefontein catchment dam, which was only 9.5% full.

Plett water users had cut consumption steadily by 33% in October and by 45% by 12 March; four of the five municipal boreholes had been refurbished with new pumping equipment; and a small treatment plant had been installed at a suburban reservoir to clean groundwater of iron and manganese.

Ngqumshe said Bitou had commissioned an environmental impact assessment for its two million litres per day desalination plant, to be funded with R20m of the disaster relief money.

Knysna municipal manager Johnny Douglas said the town’s waste-water recycling plant was under construction and should be ready by the end of April.

While the town’s rivers were under severe strain, Douglas thanked residents for “clearly adhering to the water restrictions and the call to conserve this valuable resource”.

Not only the Garden Route

The water problems, however, are not restricted to the Garden Route and more municipalities – including Cape Town and Port Elizabeth’s Nelson Mandela Bay Metropolitan Council – are turning their eyes toward the sea for relief.

In the case of Cape Town, desalination of seawater will have to be in place in four years’ time, when its growing demand for water will have exhausted existing supplies.

The Berg River is the last available river in the Western Cape which could be dammed to provide water for the city. The Berg River Dam, however, as the newest dam in the province, will meet the city’s growing demand only until 2014.

For the past 30 years, scientists and researchers have been warning of a looming water shortage, and they continue to do so, as increased economic activity, growing population numbers and more intensive farming increase the demand for water while simultaneously degrading the resource.

Reports dating back to 1993 clearly state that “South Africa’s available freshwater resources are almost fully utilised and under stress”, and that water use was not sustainable at projected growth rates.

More recently, reports by the Consulting Engineers South Africa and the World Wildlife Fund state that South Africa’s water demand will exceed supply by 1.7% in 2025, and metropolitan areas such as the Witwatersrand are expected to experience shortages as early as 2013.

In addition, the Department of Water and Environmental Affairs (DWAF) has suffered both from a lack of qualified staff and a lack of investment in infrastructure over an extended period. This has resulted in poor data and outdated dam management practices.

Based on this data, research conducted in 2004 to guide the national water resource strategy showed that we were already using 98% of all our water resources.

Water quality

Water quality is also a problem. In February, DWAF told an ad hoc parliamentary committee on service delivery that less than 11% of South Africa’s 283 municipalities have properly functioning water services, and that there is an acute risk of disease.

In April this year, there was also a warning from the north of the country that in the not too distant future, the water resource situation could see the mining industry pitted against the communities in which they operate.

Mick Davis, chief executive officer of mining house Xstrata, told the Business School of the University of the Witwatersrand that the country urgently needs to invest some R100 billion in bulk-water infrastructure and reticulation aimed at that sector. While mines can operate most of their own infrastructure, including electricity and rail transport, it is far more difficult.

At a media information session before her department’s Budget debate, Minister Sonjica said that at this stage, the budget allocation to the department was far less than what is required to avoid a water catastrophe in the country.

More than R100bn is required over the next three years to wipe out the backlog in infrastructure maintenance and to build new dams. In the interim, the department has to make do with R26.7bn until the 2012/13 budget year.

DWAF acting director-general Nobubele Ngele said that at least R60bn is required to fix water services in the country, including the treatment of sewage and the provision of safe drinking water; while only R4.4bn was made available for the present budget year.

At a previous occasion, Ngele warned that only 30 of the country’s 283 municipalities provide water services that measure up to required standards, and that water services countrywide were experiencing varying degrees of implosion.

An audit of 277 of 522 registered sewage treatment plants in the country revealed that only 32 measured up to the top standard.

Debt owed to water boards

In the meantime, the situation is exacerbated by the fact that municipalities across the country owe their water suppliers more than R1.2bn. More than half of that is unsettled long-term debt.

According to Minister Sonjica, dysfunctional municipalities are not only unable to collect money owed to them, but also increasingly are starting to default on
payments for bulk water supplies.

Answering a question put to her in parliament, she said the total amount owed to water boards by municipalities was R1.262bn. Of this, an amount of R608m is current debt and R653m outstanding long-term debt.

Worst hit was the Rand Water Board in Gauteng, which is owed R443.7m, followed by Bushbuckridge Water at R151m, Sedibeng Water at R146m, and Umgeni Water at R135m.

The history of the figures involved seems to indicate that the situation is worsening.

Water boards are responsible for pulling together all the water resources within their respective area of jurisdiction and ensuring that it is purified and delivered to where it is required. Their income is almost exclusively from the sale of water to municipalities, and the present situation is placing them under considerable strain.