By Mlungisi Shabalala, 31 October 2023
uMngeni-uThukela Water (UUW) continues to monitor the El Niño Southern Oscillation (ENSO) signal and the latest model updates indicate that the ENSO remains in an El Niño state (Australian Bureau of Meteorology; International Research Institute for Climate and Society). According to the International Research Institute for Climate and Society, the probability of the sustenance of El Niño conditions remains high (100%) for the upcoming summer season.
Coastal areas receive heavy rainfall in October 2023
Most parts of uMngeni-uThukela Water’s operational area have received above-average rainfall during the month of October 2023. As a result, most UUW-operated dams remain in a relatively healthy status. It is important to note that, contrary to the characteristics of an El Niño cycle, the rainfall received in October 2023 has been relatively high, when compared to October 2022 (a La Niña year). This was due to the two cut-off low systems which brought heavy rainfall and cool temperatures along the coastal areas during the month of October. As a result, uMngeni-uThukela Water sites along the coastal belt received above-normal rainfall during October 2023, with the South Coast, North Coast and Mhlathuze areas receiving 331%, 212% and 551% of rainfall received during October 2022, respectively. Notably, Eshowe received 355 mm of rainfall during October 2023, a tenfold increase from the 30 mm received in October 2022. This uncharacteristically high rainfall received during October 2023 has improved the storage in most UUW-operated dams. As a result, the risk of non-supply remains low for most areas supplied by uMngeni-uThukela Water in the short-term.
Is this the end of El Niño?
Although most of uMngeni-uThukela’s area of operation has received above-average rainfall during October, climate models still suggest sustenance of El Niño conditions over the entire summer season. El Niño cycles are associated with dry and hot conditions, posing a risk to water resources availability. In addition, most dams situated in the coastal areas (where most rainfall was received during October) are relatively small and are characterised by rapid response to changes in rainfall patterns. Therefore, the predicted sustenance of El Niño conditions during the summer season poses a risk to the long-term availability of water resources in these dams.
Water users are advised to remain alert and follow weather updates (as well as warnings) from the South African Weather Service. In addition, stakeholders are encouraged to use water sparingly, in order to reduce pressure on our already-stressed water resources. uMngeni-uThukela Water will issue an update at the end of November 2023.
