Phase 2 of the long-awaited Lesotho Highlands Water Project (LHWP) has broken ground.
LHWP Phase 2, building on Phase 1, which was completed in 2003, includes the construction of the Polihali dam and transfer tunnel, as well as the Senqu bridge above the Senqu river.
“As we all know, this project was delayed for a few years, but it is pleasing that the challenges have been overcome and we can do the sod-turning today,” said President Cyril Ramaphosa on May 23 during the sod-turning ceremony in Lesotho.
The LHWP, the biggest infrastructure investment South Africa has participated in, outside the country’s borders, is a good example of public–private collaboration to build key public infrastructure, he said, noting that most of the estimated R40-billion in capital required for this phase will be raised in South Africa’s financial markets by the Trans-Caledon Tunnel Authority.
“The private sector is playing a similar role in many of our other major water resource infrastructure projects in South Africa.”
In November, the Lesotho Highlands Development Authority (LHDA) announced the award of two contracts – LHWP Phase 2’s biggest to date – for the construction of the Polihali dam and Polihali transfer tunnel, signalling the start of the “final lap” of the water transfer infrastructure construction.
The Polihali dam, a 165-m-high concrete-faced rockfill dam, similar to the Mohale dam, which was constructed in Phase 1 of the LHWP, will create a reservoir on the Senqu and Khubelu rivers with a surface area of 5 053 ha. The infrastructure also includes a spillway, a compensation outlet structure and a mini-hydropower station.
The Polihali transfer tunnel will transfer water by gravity from the Polihali reservoir to the Katse reservoir, before the water is transferred through the delivery tunnel to the Muela hydropower station, which was constructed in Phase 1, and then on to the Ash river outfall outside Clarens, in the Free State, on its way to Gauteng.
Water transfer is expected to start in 2028, with commissioning of the Oxbow Hydropower Scheme, for which procurement for the design and construction supervision, also critical to Phase 2, is currently under way, expected to follow in 2029.
The water South Africa receives from Lesotho augments the Integrated Vaal River System, which supplies water to Gauteng and its surrounding areas.
Phase 2 will increase the current water supply from 780-million cubic metres a year incrementally to more than 1.27-billion cubic metres a year by completion in 2028.
“Once Phase 2 is completed, more than 400-million cubic metres of water will flow every year from the upper reaches of the Senqu river in Lesotho through the existing conveyance infrastructure to the Vaal dam in South Africa,” Ramaphosa commented.
The project includes the construction of hydropower facilities to provide electricity for Lesotho.
“We are determined that this massive transborder project should equally benefit the people of Lesotho and South Africa. In addition to the royalties Lesotho receives from the LHWP, local jobs have been created and new roads have been built in the Kingdom.
“It has been critical for Lesotho and South Africa that all communities affected by the construction of the Polihali dam were consulted, that there should be fair compensation and relocation to alternative housing nearby,” he said.