The three-year construction of the 825m long and 90m high Senqu Bridge is set to begin soon after the Lesotho Highlands Development Authority (LHDA) awarded the $2 billion construction contract to a multinational consortium.
LHDA selected Webuild, based in Italy; South African companies Raubex Construction and Enza Construction and Lesotho-based Sigma Construction collectively form the WRES Senqu Bridge Joint Venture (JV).
The WRES joint venture comprises South African, Lesotho and international companies as required by the Lesotho Highlands Water Project (LHWP) Phase II Agreement.
Subcontractors include South African companies EXR Construction and Post Tensioning and Structural Solutions; the Austrian Gleitbau-Geselschaft; and the French company Freyssinet International et Cie.
The Senqu Bridge is the largest of the three bridges that will be constructed under Phase II to span the Polihali Reservoir and is larger than the Mphorosane Bridge over the Malibamats’o River, which spans the Katse Dam and was built as part of LHWP Phase I.
The design of the bridge took into consideration the long, cold and harsh winter conditions of the highlands of Mokhotlong.
“Experience and expertise are key to delivering a sophisticated and technically challenging project of this type, which will be a first for the LHWP and Lesotho. The Senqu Bridge will not only be 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 by driving sustainable economic growth,” the director said. division of phase II. Ntsoli Maiketso.
The Polihali reservoir in the valleys and catchment areas of the Senqu, Khubelu, Mokhotlong, Moremoholo and Sehong-hong rivers, which will be formed by the construction of the Polihali dam, will have an area of about 5,000 ha.
Apart from the three main bridges, the restoration of access across the reservoir also involves the construction of new sections of access road to the bridges that connect the outbound A1 road, which is the main road between Mokhotlong district in the north -is mountainous of the country and the capital Maseru.
Work on the design of the bridge began in 2018, led by Zutari, formerly Aurecon Lesotho.
Zutari also designed the Mabunyaneng and Khubelu bridges, the other two major bridges to be constructed under Phase II.
The call for tenders for the construction of these two bridges is currently being evaluated.
Zutari will also oversee the construction of the three bridges.
Due to the depth of the valley and the terrain of the area, the deck will be built gradually from both abutments, which will minimize disturbance to the surrounding work area and increase worker safety.
An in situ mid-span segment of the central span will connect the two parts to form a continuous deck. The shape of the pile is ideal for construction with slip formwork.