The Zambezi River Authority (ZRA) has revealed that approximately 16 Billion Cubic Meters (BCM) of water have been earmarked for power generation operations at Kariba Dam in 2024. The allocation is to be evenly split between Zesco Limited (ZESCO) and Kariba Hydro Power Company (KHPC) for the upcoming year.
Munyaradzi Munodawafa, Chief Executive Officer of ZRA, made the announcement, citing the 2023-2024 rainfall forecasts provided by the Southern Africa Climate Outlook Forum-27 (SARCOF-27) and corresponding projections from the National Meteorological Agencies of Zambia and Zimbabwe as the basis for the decision.
Munodawafa explained that both agencies predict a high probability of a normal to below-normal rainfall season for the Kariba Lower Catchment and a normal to above-normal season at the Kariba Upper Catchment. These projections are influenced by the increasing occurrence of El Niño weather conditions, expected to have a significantly negative impact on the rainfall season in Southern Africa.
According to hydrological simulations conducted by the Authority using the Kariba Inflow Forecasting System (IFS), there is a high likelihood of a below-average rainfall season. This, in turn, will result in below-average inflows into Lake Kariba, adversely affecting the volume of water available for power generation in 2024.
Monitoring Zambezi River flows at Victoria Falls through the IFS system revealed a flow rate of 472m3/s on December 27, 2023, slightly lower than the recorded 482m3/s on the same date in 2022. Similarly, at the Chavuma Gauging Stations, the flow was 324m3/s on December 27, 2023, showing a decrease of 41m3/s compared to the flow recorded on the same date in 2022, which was 337m3/s.
Munodawafa highlighted that Lake Kariba continues to experience lower inflows, primarily due to poor rainfall season activities and lower inflows compared to outflows. As of December 27, 2023, the recorded Lake Level was 477.12m with 7.25 BCM, representing 11.19 percent live storage.
In light of these conditions, Munodawafa emphasized the importance of the two power-generating utilities adhering to their respective water utilization plans for 2023. He recommended the highest maintenance of possible live storage going into 2024 as a buffer against anticipated below-normal inflows.
The Authority will engage the two utilities through weekly Joint Technical Committee meetings to ensure compliance with approved water utilization and power generation plans, ensuring the sustainable management of the Kariba Reservoir. Eng. Munodawafa urged power utilities to explore alternative sources of power to complement generation at Kariba and address any potential power generation deficits due to lower water allocations in 2024.
He further noted that Zambezi River Flows recorded at key gauge reading stations have been consistently lower since the start of the 2023/2024 rainfall season, with Victoria Falls showing signs of a minor increase in water levels. The situation will continue to be monitored closely as the region navigates through the complexities of water resource management and power generation.