Water experts predict that at least two Western Cape dams could be filled to capacity in the coming days due to recent heavy rainfall.
Water expert and academic at the University of Cape Town, Dr Kevin Winter said: “As you know we are getting good rainfalls right now with most of the main dams overflowing. Theewaterskloof is still filling up (77% when I last looked) and Voelvlei (just over 50% full).
“These are the only two dams that have yet to reach 100%. Rainfall over the last 24 hours will improve Theewaterskloof, but it will take a few days before we can confirm how much the inflowing streams have improved the levels.
“Voelvlei is a little unknown right now because the cold front that has just passed over brought widespread rainfall over the Southern Cape, but I can't see any data over the 24 hours until later tomorrow. In any case, it takes a few days before the dams fill after significant rainfall”.
Winter said that the Western Cape water storage system had records that go back to 2008 on the City's water dashboard.
“Since 2008 there have been six occasions when the storage dams have been full to overflowing. The last time was 2014 when the overall storage levels were at 100%,” he said.
The Department of Water and Sanitation (DWS) confirmed an 11% increase in water capacity in the Western Cape dams from this time last year while experts are expecting a further increase in the coming days
DWS said earlier this year there was widespread panic from the water users at the slow pace at which the province’s dams were filling up.
“Understandably, at the time the dam levels showed a notable decline compared to the two previous years. Due to heavy rainfalls experienced throughout the Western Cape in the last two weeks, the state of the Western Cape storage Dams saw a significant increase. The Cape Town systems dams recorded a combined 79.31% full capacity compared to 63.92% this time last year.
“The Western Cape State of Dams which indicates the total storage for all DWS monitored dams in the province is at 68,71%, which is above 11% increase compared to last year. Thirteen dams, including Clanwilliam, Ceres, Bulshoek, Karee, and Kwaggaskloof dams increased by over 5%.
“Encouraging is the fact that no dams decreased this week. Although the Gouritz Catchment has some significant rainfall, the Coastal Belt gets most of its rain during the summer season.
“Ten of the dams in this catchment are at 100% of which most are agricultural dams. The Theewaterskloof Dam, the largest dam in the province accounting for significant water supply (54% of the Western Cape Water Supply System Dams) reached 76,67%, a healthy yield for this time of the year.
The department was at the way the dam storages were replenishing across the province.
“It is also noteworthy the rainfall experienced so far is comparable to rainfall received a decade ago, averaging around 68% of full capacity storage for the Western Cape State Dams,“ the department said.
Mayco member for water and sanitation, Zahid Badroodien, said dams that supply Cape Town with drinking water saw a sharp increase recently due to the heavy rain and by yesterday (Thursday June 15) stood at 86,1%.
“Rainfall data recorded since the beginning of June at dams that supply the city, shows rainfall to be well in excess of long-term averages for this time of year.
“The City is monitoring all its dams closely. In the meantime, the City continues to invest in Cape Town’s New Water Programme (NWP). The NWP, 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 our primary water supply to navigate future climate shocks and droughts,” he said.
Senior forecaster at the South African weather services, Stella Nake said the current rainfalls will contribute significantly to dam levels in the Western Cape.