The ongoing maintenance of the Lesotho Highlands Water Project (LHWP) tunnel is progressing according to schedule, with completion expected by March 2025. This was confirmed by Deputy Minister of Water and Sanitation David Mahlobo during a recent inspection of the tunnel in the Free State on Friday, 15 November.
Accompanied by Deputy Minister Sello Seitlholo and other officials, Mahlobo visited the tunnel, which has been shut down since October for essential maintenance. The 38-kilometer tunnel will remain out of service until 31 March 2024 as part of routine inspections and repairs aimed at maintaining its integrity.
Mahlobo provided an update on the state of the tunnel, reporting that it was in good condition with no significant issues identified. “We are satisfied with the progress made by all involved parties to ensure that the maintenance work is proceeding smoothly,” he said. The maintenance is being carried out by the Trans-Caledon Tunnel Authority (TCTA) on the South African side and the Lesotho Highlands Development Agency (LHDA) in Lesotho.
The Deputy Minister explained that the tunnel system requires general inspections and repair work at approximately five-year intervals to ensure its long-term functionality and reliability. As a result of the current shutdown, the annual water transfer will decrease by 80 million cubic meters, with a projected transfer of 700 million cubic meters in 2024, compared to the usual 780 million cubic meters.
The water flowing through the LHWP tunnels supplies raw water to several municipalities in the Free State, including Dihlabeng, Nketoana, and Mafube, as well as to agricultural irrigators in the region. The Ash and Liebenbergsvlei Rivers, which receive water from the project, ultimately feed into the Vaal Dam, a critical source of water for much of South Africa.
André Olivier, Senior Engineer at Raubex Construction, which is overseeing the maintenance work, confirmed that there has been no structural damage to the tunnel. Minimal repairs are being made to the concrete sections, while the steel-lined portions are being sandblasted and refurbished. The previous inspection in 2019 determined that the steel liner would need to be completely overhauled during this maintenance cycle to ensure its continued reliability.
