Cape Town - The latest edition of the Cape Town Water Outlook, which advises on the current status of the city’s water supply and water security, shows that even with the City’s New Water Programme, most of its water will continue to come from rain-fed dams over the next 20 years.
This will mean that Cape Town will still need to implement water restrictions during drought periods when rainfall is low, however the frequency and severity of restrictions should not exceed a 30% required saving on water.
This was stated in the 10th annual edition of the Water Outlook, which is available on the City’s website and was released on Monday.
Water and sanitation Mayco member Zahid Badroodien explained the City’s New Water Programme – which includes projects such as desalination, groundwater schemes and reuse – is part of the City’s long-term water strategy to help reduce Cape Town’s dependence on rainfall and dam storage as its primary water supply to navigate future climate shocks and droughts.
According to the outlook, if the rainfall experienced in 2022, which was well below average, was experienced again this winter, low-level water restrictions would probably need to be implemented during the coming summer.
The City adopted a precautionary approach and has urged residents to use water sparingly since the beginning of summer last year. Now it is targeting a 10% saving on water usage for the rest of 2023 – without imposing formal restrictions.
Badroodien said: “Due to climate change and its associated long-term effects, the City’s view remains that we are in a possible 10-year drought. What is unclear is whether the change will be gradual or sudden, as seen in other parts of the world.
“If we are in fact experiencing a change in climate, all of the plans being put in place to get water from a diverse mix of sources, including water reuse, will need to be accelerated.”
The Department of Water and Sanitation indicated that the persistent rainfall from last week brought significant improvements to dam storages in the Western Cape. The hydrological report showed that the Western Cape Water Supply System now sits at 69.52%, a notable increase from last week's 63.44%.
DWS national spokesperson Wisane Mavasa said: “This should not be a reason for being complacent. It will take significant rains to fill some dams. It is now the start of the Western Cape’s winter rainfall season so the department is hopefully that cut-off lows and predicted precipitation will increase the dam levels.
Stefaan Conradie, a PhD student in climatology from the Climate Systems Analysis Group at UCT, said the unusually wet weather in the catchment areas since mid-December had now almost offset the very dry extended winter (roughly April to October) in 2022.
“Even an average or slightly below-average winter from here should see the dams reaching full capacity this year,” he said.
Having said that, he warned that a dry winter is still possible and that residents should heed the call by the City to continue to use water sparingly - at least until the dams are near capacity.