South Africa and Lesotho to Unveil R2.4 Billion Senqu Bridge

A Milestone for the Lesotho Highlands Water Project

On April 22, 2026, South Africa and the Kingdom of Lesotho will officially inaugurate the Senqu Bridge. Located in the Mokhotlong District of Lesotho, this R2.4 billion structure is a critical component of Phase II of the Lesotho Highlands Water Project (LHWP), a strategic partnership designed to ensure water security and energy generation for both nations.

Engineering Excellence in Challenging Terrain

The Senqu Bridge is the largest of three major bridges built for Phase II, designed to maintain vital transport links once the Polihali Reservoir is filled.

• Dimensions: The bridge measures 825 metres in length and stands approximately 90 metres high.
• Innovative Design: It is the first extradosed bridge in Lesotho, a sophisticated hybrid of cable-stayed and prestressed girder designs.
• Construction Method: Engineers utilized an incremental launching method, which improved safety and minimized environmental impact in the rugged mountain terrain.

Strategic Importance: Water and Energy Security

The LHWP is a multi-phased project that harnesses the Orange–Senqu River system. Phase II builds upon the foundation laid by Phase I (completed in 2003) to significantly expand the system’s capacity.

Key Components of Phase II:

• Polihali Dam: A 165-metre-high concrete-faced rockfill dam.
• Transfer Tunnel: A 38-kilometre tunnel connecting the Polihali and Katse reservoirs.
• Capacity Increase: Total water transfer to South Africa’s Integrated Vaal River System will rise from 780 million to 1,270 million cubic metres per year.

Socio-Economic Impact

The construction of the Senqu Bridge has served as a catalyst for regional economic growth:

• Employment: The project generated approximately 250,000 person-days of employment, with a peak workforce of 1,200, primarily comprised of local Basotho workers.
• Local Inclusivity: Procurement was structured to benefit local enterprises in both countries, including significant participation from South African black-owned firms.
• Connectivity: The bridge secures the A1 route, ensuring that Mokhotlong and surrounding communities remain connected to the national capital, Maseru, even after existing roads are submerged by the new dam.

Regional Cooperation and Governance

The LHWP stands as a flagship of African regional integration. Managed through joint governance structures, it reflects a high level of interdependence. While South Africa gains the water security necessary to support its economic hub in Gauteng, Lesotho benefits from hydropower generation, infrastructure development, and consistent revenue through water royalties.

Ahead of the bridge launch, officials will also unveil the Tunnel Boring Machine (TBM) on April 20, a specialized piece of equipment that will drill the 38-kilometre connection between the reservoirs, signaling that Phase II is maintaining strong momentum toward its final completion goals.