Water users of the Vaal River System have been reminded about the upcoming six-month closure of the Lesotho Highlands Tunnel for planned maintenance work.
The planned maintenance work on the transfer and delivery tunnels of the Lesotho Highlands Water Project (LHWP) is scheduled to start from 1 October 2024 to 31 March 2025.
The tunnel system consists of a Transfer Tunnel, linking Katse Dam with Muela Power Station and Muela Dam, and a Delivery Tunnel, linking Muela Dam with the Ash River Outfall Works between Clarens and Bethlehem.
The Department of Water and Sanitation said the inspections and maintenance of the tunnels are conducted at intervals not shorter than five years and not exceeding 10 years.
“The last maintenance was conducted in 2019. During the shutdown of 2019 it was found that the steel liners in the tunnel urgently need extensive maintenance on both the Republic of South Africa and Lesotho side,” the department said.
It noted that this process cannot be done in a shorter period than six months.
The planned maintenance work is being overseen by the Lesotho Highlands Water Commission, a joint governance body between South Africa and Lesotho and will be jointly undertaken by the Lesotho Highlands Development Agency (LHDA) and the Trans Caledon Tunnel Authority (TCTA).
The work required to be undertaken during the period includes grit-blasting the steel-lined section around the entire circumference and re-applying corrosion protection on the tunnel lining, as well as other maintenance and repair work identified during the 2019 maintenance shutdown.