The South African Academy of Engineering is calling on the South African Government to engage urgently with Lesotho to end the wasteful release of water from Katse and Mohale dams.

Water is being released to generate hydropower in Lesotho, even when the Vaal and Bloemhof dams in South Africa are full and overflowing although the Lesotho dams are less than 65% full. As a result, water that could have been stored in Lesotho as a reserve in case of future drought in South Africa, is being permanently lost.
The Vaal and Bloemhof dams are key components of the “Integrated Vaal River System” (IVRS) that links 14 dams from four different river basins and supplies water to Gauteng and surrounding regions.

Supply from the IVRS will come under increasing strain until the Polihali dam, the next stage of the Lesotho Highlands Water Project, is completed in 2028. It is critical that all options are considered to maintain reserves to ensure that the IVRS region is resilient to droughts during this period.

The SAAE has urged the Minister of Water and Sanitation and his counterparts in the Departments of Minerals and Energy, Public Enterprises, International Relations and the Treasury to engage with Lesotho and to agree on operating arrangements that maintain South Africa’s resilience to drought and on compensation to Lesotho for loss of income that might be incurred from reduced water transfers and electricity generation at their Muela Hydropower Station.

The SAAE also notes that Lesotho may also benefit from revised arrangements if ESKOM would agree to take electricity from Lesotho during peak periods when its value is greater. Higher dam levels in Lesotho would also support their tourism, recreation and fish farming activities that are negatively affected when dam levels fall. In 2020, the level in Mohale Dam fell to just 5% of its capacity.
The SAAE has offered to support the process if required.