LEADING WATER PROJECTS
A shed housing the water treatment plant
Phase II of the Lesotho Highlands Water Project (LHWP) comprises the construction of the Polihali Dam and reservoir, water transfer tunnel and the associated access roads, bridges, accommodation, electrical transmission lines and telecommunications infrastructure.
Lesotho Highlands Water Project Phase II:
T
he LHWP Phase II builds on the successful completion of Phase I in 2003. It delivers water to the Gauteng region of South Africa and uses the water deliver y system to generate electricity for Lesotho.
Polihali diversion tunnels The two diversion tunnels were constructed in preparation for the Polihali Dam construction and ahead of the appointment of the dam contractor. The Lesotho Highlands Development Authority (LHDA) celebrated the double breakthrough of the tunnels in August 2021, marking the completion of 1 870 m of excavation. Excavation inside the two Polihali diversion tunnels commenced in June 2020 and mostly advanced from the outlets. Construction was completed in November 2021. The contractor and consultant have demobilised from site.
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IMIESA March 2022
Diversion tunnel outlets
Overview & Update
Bulk power
Environmental milestones
The electrical infrastructure required for the Phase II development includes the construction of new substations, upgrading of existing Lesotho Electricity Company (LEC) substations, the construction of new power lines, and the diversion of the existing LEC 33 kV distribution network between Letšeng and Mokhotlong, which is below the Polihali Dam full supply level. A 33 kV power line of 2.2 km from Tlokoeng to Polihali to supply early power for the advance infrastructure contracts and the Polihali village prior to the completion of the main power from Matsoku was completed in June 2021. The construction of a 38 km 132 kV transmission line between Matsoku substation and the new substation at Polihali have been completed and both were energised in mid-Januar y 2022.
Environmental and social impact assessments and environmental management plans for the Polihali Western Access Road (PWAC) and associated infrastructure are completed. Records of decision (RoDs) authorising the construction of the Polihali Dam, Polihali Transfer Tunnel, PWAC and its associated components have been granted by Lesotho’s Ministr y of Tourism, Environment and Culture. Furthermore, the environmental management plans have been approved, while the RoDs for the Polihali North East Access Road (PNEAR), the construction of the diversion tunnels and for the quarries and borrow pits associated with the major components like the Polihali Dam and Polihali Transfer Tunnel and the major bridges have been granted.
Procurement milestones Polihali and Katse infrastructure works The works at Polihali and Katse – including the potable water supply system and sewer reticulation to permanent and temporary residential areas, water treatment facilities, access roads and street lighting – are complete.
Main works milestones include the procurement of the contractors for the Polihali Dam, Polihali Transfer Tunnel and major bridges. The award of the contracts is expected in 2022. The completion of additional hydropower feasibility studies and the Lesotho government’s approval to proceed with
