Water resources –prepare for a drought

The maximum consumption that SA’s water resources can sustain will be reached in about five years,warns Engineering Council of SA vice-president Thoko Majozi

With floods causing havoc in seven provinces,it may be hard to believe that a water shortage of crisis proportions is looming. The maximum consumption that SA’s water resources can sustain will be reached in about five years,warns Engineering Council of SA vice-president Thoko Majozi.

“We have known for decades that SA will run out of water,” says Majozi. “It’s time everyone recognised that we live in a water-scarce country.”

So scarce that SA is the world’s 30th-driest country,says Jeremy Taylor,founder of water conservation company Water Rhapsody. He adds that SA has less water per person than its drier neighbours Botswana and Namibia.

SA has seen a little of what a prolonged drought can do in the Western Cape,where towns such as Sedgefield,Mossel Bay and Knysna have resorted to costly seawater desalination to stave off disaster.

But that’s nothing compared to what is heading Cape Town’s way,warns Taylor. He explains that the La Niña climate pattern causing floods in the northern provinces will have the reverse effect in the winter rainfall area.

Backing his view is a prediction by the weather service at Cape Town International Airport indicating rainfall 33% below normal during the city’s wettest months,April,May and June.

“Water reserves in dams serving Cape Town are falling at a record 2,8%/week and will be at about 45% when the first rains fall,” says Taylor. If dams are not 80% full by October,expect restrictions aimed at cutting consumption by 30%,he adds.

This will only be the start of Cape Town’s water crisis . If the normal seven-year rain cycle holds,2012 and possibly 2013 will also be dry years,he predicts.

It can’t build more dams,so Cape Town is turning to other solutions,says the mayoral committee member for utility services,Clive Justus. Among these is a R750m upgrade of water reticulation systems in an effort to cut water loss from burst water mains and leaks,which in 2008 accounted for 19% of the city’s water use.

But,says Justus,replacing Cape Town’s 10800km of water mains is impossible and the city is looking at other options,including extracting water from the Table Mountain Group aquifer. Justus says an R8m drilling project is under way.

Taylor argues that the initiative is fraught with risks,such as damaging water sources along the aquifer,which extends to Port Elizabeth. Majozi agrees. “Often when people react to a crisis they do not think clearly of long- term consequences,” he says.

The answer,stress Taylor and Majozi,is water conservation,including recycling and reuse of water from basins,washing machines,baths and showers by households. Termed grey water,it constitutes up to 70% of household water usage,which in turn represents about 30% of SA’s water usage.

By using grey water in toilets and for gardens,and adopting measures such as collection of rainwater in tanks,households can cut water use by up to 70%,says Taylor.

For Gauteng households the outlook is not as bleak. Majozi says the province has secure supplies from the Vaal River and Lesotho — for now. But,he warns,Gauteng faces a serious problem of another type:pollution of its water supplies by industry.

Industry accounts for only 10% of water consumed but causes immense damage to the environment,including rivers,says Majozi. Proven technology is available to solve the problem without disrupting the production process. “I don’t understand why it’s not being done,” he says.

“If we don’t act now it will be too late,” Majozi warns. He says decisions taken now will determine whether we lurch from one water crisis to another or become a country that secures optimal use of a scarce resource as vital as energy to economic development.

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