The Lesotho Highlands Development Authority (LHDA) completed the construction procurement for the remaining two major bridges to be built under Phase II in late August, awarding the M511 500 000 contract to the Concor-Nthane Brothers M&K Bridges Joint Venture.
Work on the contract commenced on 29 August and the two bridges across the Mabunyaneng and Khubelu rivers are expected to be completed towards the end of October 2025.
The JV is comprised of main partners Concor Construction (Pty) Ltd (South Africa) and Nthane Brothers (Pty) Ltd (Lesotho) and sub-contractors: Post Tensioning and Structural Solutions (Pty) Ltd (South Africa) and Bridge Joints and Rehabilitation Contractors (Pty) Ltd (Lesotho).
The construction contract of the biggest of the trio of bridges – the Senqu Bridge – was awarded in late 2022. At the Senqu Bridge site construction of the temporary site facilities is well progressed and excavations have started for the massive pier and abutment foundations necessary to support the 825 m long and 90 m high bridge.
The three major bridges, when complete, will provide access to Mokhotlong town across the reservoir even at full supply and retain connectivity to the national road network along the A1, the main road between the Mokhotlong district in the mountainous north-east of the country and the capital, Maseru.
“The impounding of the Polihali reservoir will submerge existing roads and tracks, affecting communities in the valleys and tributary catchments of the Senqu, Khubelu, Mokhotlong, Moremoholo and Sehonghong rivers. The major bridges along with a network of feeder roads and the main access roads to the project area all contribute towards minising this disruption and help to restore community access to healthcare facilities, schools, shops and markets,” said Gerard Mokone, Manager of the LHDA’s Polihali Branch.
As in the case of the Senqu Bridge, the design of the Khubelu and Mabunyaneng bridges has taken into consideration the challenging, high altitude construction conditions and the Mokhotlong highlands’ long, cold and harsh winter conditions. The health and safety of workers on the bridge construction is of particular importance.
The Khubelu Bridge will be approximately 270 metres long with nine 30 m spans and two abutments. Mabunyaneng Bridge, the smallest of the three major bridges will be approximately 120 m in length and has four 30m spans and two abutments. The bridges will both be 13.55 metres wide.
“The trio of bridges will not only form part of the safe and efficient road infrastructure network constructed under Phase II but will be a major tourist attraction contributing to long term benefits in stimulating sustainable economic growth,” Ntsoli Maiketso, Phase II Divisional Manager, stated.
Work on the design of the Mabunyaneng and Khubelu bridges started in 2018, led by Zutari, formerly Aurecon Lesotho. Zutari also designed the Senqu Bridge and is supervising the construction of the three bridges.
Phase II of the the Lesotho Highlands Water Project entails the construction of the Polihali Dam, the 38km Polihali Transfer Tunnel, the associated infrastructure and a hydropower scheme at Oxbow. It builds on the successful completion of Phase I in 2003.
The LHWP delivers water to the Gauteng region of South Africa and utilises the water delivery system to generate hydroelectricity for Lesotho. Phase II will increase the current supply rate of 780 million cubic metres per annum incrementally to more than 1 270 million cubic metres per annum. At the same time, it will increase the quantity of electricity generated in Lesotho and is a further step in the process of securing an independent electricity source to meet Lesotho’s domestic requirements and reducing the country’s dependence on imported energy.