According to the National Treasury, and as confirmed by international experts, temporary small-scale desalination capacity was costly and would not make a material difference in time.
“The City of Cape Town and the Department of Water and Sanitation must agree on plans to develop groundwater resources, and build permanent wastewater reuse and/or desalination capacity at an appropriate scale and in a cost-effective manner.”
The Treasury said expertise in contracting large projects developed through the renewable energy programme had been availed to the City, in procuring capacity on a larger scale.
Finance Minister Malusi Gigaba said the severe drought conditions were affecting large parts of the country and was placing strain on the supply of water to nearly four million people in Cape Town.
“The national government will, however, continue to work with municipalities to respond effectively to the water crisis,” he said.
Gigaba said R6 billion has been set aside for drought relief alleviation and public infrastructure investment in the 2018-19 financial year.
A further R473 million has been allocated for disaster relief for provinces and municipalities.
While the City implemented various programmes in response to the drought, the Treasury said most residents have shown impressive civic responsibility in curtailing their water use.
“This is a result of expanded public awareness of the crisis, resulting in households examining and radically reducing their own consumption patterns.
"If the City’s targeted water saving is achieved and there is some winter rain, then a Day Zero scenario can be avoided.”
On Tuesday, the City pushed back Day Zero by another month, to July 9, following reduced consumption of water.
The Treasury said while the City had halved its summer water usage from 1.2 billion litres a day to below 600 million litres a day, usage should be further reduced to 450 million up to July.
“A lengthy interruption of urban water supply would threaten public health and negatively affect mist economic activities.”'