Cape dam levels drop‚ city mulls emergency water supply schemes

Cape Town has roughly 103 days of useable water left in its dams.

There is effectively 18.6% of usable drinking water left in the city’s dams‚ said mayoral committee member for informal settlements‚ water and waste services and energy‚ Xanthea Limberg.

Dam levels have dropped by 1.4% in the space of a week with residents consuming 750 million litres a day‚ outstripping a target of 700 million litres per day set by the city.

“We are in the midst of one of our worst droughts of the past century. Cape Town is in a water-scarce region and is experiencing the impacts of climate change with an increased frequency of drought events‚” said Limberg.

She predicted that dam levels would reach extremely low levels by the onset of the 2017 winter and warned that they were unlikely to recover satisfactorily‚ should average to below average rainfall be experienced during winter.

Limberg said the city was considering various small-scale emergency water supply schemes to bolster its supply of water in the short term. They include: - The emergency drilling of boreholes into the Table Mountain Group Aquifer with a yield of approximately 2 million litres per day. - A small-scale desalination package plant‚ located along Cape Town’s north-western coastline with a yield of approximately 2 million litres per day. - Intensifying the city’s pressure management and water demand management programmes to further reduce demand.

In the event of below average winter rainfall‚ the city will extract more water from the Table Mountain Group Aquifer and Cape Flats Aquifer‚ plus expand its seawater desalination plant.

“The capital costs of the emergency schemes are currently estimated at R315 million over three financial years‚” said Limberg.