Name of the Project
Lesotho Highlands Water Project (LHWP) – Phase II.

Location
Lesotho.

Project Owner/s
The Lesotho Highlands Development Authority (LHDA) is the implementing authority and the Lesotho Highlands Water Commission the oversight authority.

Project Description
Phase II of the LHWP builds on the 2003 completion of Phase I, which supplies water to Gauteng and uses the water delivery system to generate hydroelectricity in Lesotho. 

Phase II will increase the current water supply from 780-million cubic metres a year incrementally to more than 1.27-billion cubic metres a year. 

Phase II of the LHWP will be implemented in two distinct components: a water delivery system to augment the delivery of water to South Africa and a hydropower generation system, which will increase the current electricity generation capacity in Lesotho.

Polihali dam
The Polihali dam is a concrete-faced rockfill dam. It will create a reservoir on the Senqu and Khubelu rivers with a surface area of 5 053 ha.

The Polihali dam adds 2.33-billion cubic metres in storage capacity to the LHWP and will increase the current yearly supply rate capacity from 780-million cubic metres to 1.27-billion cubic metres, contributing towards meeting South Africa’s increasing water needs. 

The additional flow of water from Polihali will simultaneously increase power generation within Lesotho to assist in meeting Lesotho’s domestic needs and reducing the country’s dependence on electricity imports.

The reservoir capacity will be 2.325-billion cubic metres and, apart from the main dam embankment, the project includes a 43-m-high saddle dam, also a CFRD; a 33-m-high upstream cofferdam; a 105-m-high intake tower with a 5 m outlet tunnel/chute to release 300 m³/s; a 98-m-long ogee spillway designed to discharge 4 300 m³/s; two bridges and an outlet house incorporating compensation and flood release valves; and a 2 × 2.1 MW mini hydropower station.

Polihali to Katse tunnel
The estimated 38-km-long, nominal bore 5-m-diameter Polihali–Katse dam tunnel will be constructed to transfer water from the Polihali reservoir to the Katse reservoir.
The Polihali dam will create a reservoir on the Senqu and Khubelu rivers with an estimated surface area of 5 053 ha and a full supply storage capacity of 2.325-billion cubic metres.

Advance infrastructure
Phase II required extensive infrastructure development before the mobilisation of contractors for the two main water-transfer works contracts of the Polihali dam and transfer tunnel. The Polihali intake site used the infrastructure developed to build the Polihali dam and transfer tunnel. 

This includes feeder roads and bridges around the reservoir to connect affected communities, power supply systems, construction camps and communications. 

The infrastructure at Katse dam and in the Matsoku valley will also be available for the Polihali–Katse tunnel construction.

Hydropower
Further feasibility studies for the hydropower component of Phase II have concluded that conventional hydropower is the more feasible option to meet Lesotho’s energy needs.

Three potential sites were identified: two on the Senqu river and a third site at Oxbow, on the Malibamat’so river. 

The hydropower tender design has been approved by the government of Lesotho and procurement to solicit a service provider for detailed design and supervision of the Oxbow Hydropower Scheme is completed, and awaiting contract award. The plan is to commission it shortly after the water transfer component in 2031

Potential Job Creation
About 9 000 jobs have already been created under Phase II. An additional 3 000 jobs are expected to be created at the height of the construction phase of the main works of Phase II.

Capital Expenditure
R53-billion. The cost of the hydropower component is yet to be established.

Planned Start/End Date
According to the current master programme, water delivery is scheduled for 2028. 

Timeous construction of the Polihali dam and transfer tunnel is critical to meeting the water delivery deadline of the project.

The project broke ground in May 2023.

Latest Developments
After seven months of tunnelling on the Polihali transfer tunnel construction site, the LHDA has achieved the successful breakthrough of the upper intake tunnel into the lower intake tunnel.

This brings the LHDA one step closer to realising the full potential of the Polihali dam: increasing the volume of water transferred to South Africa, increasing the volume of hydropower generated in Lesotho, enhancing the livelihoods of the Basotho, and contributing to the economies of Lesotho and South Africa.

The intake tunnels will allow for water from the 5 042 ha Polihali reservoir to enter the transfer tunnel for delivery to the Katse reservoir, the centre point of the LHWP.

The authority will now embark on the next two critical phases in the project, one of which is the safe start of the impoundment of the Polihali reservoir, made possible by the collapse of the upper intake tunnel into the lower one.

The process allows for a controlled and secure increase in water levels up to the lower tunnel, which can then be temporarily sealed.

The second phase allows for continuous debris removal from the remaining tunnel works.

As construction progresses towards its connection with the access adit, debris can be efficiently cleared through the upper intake tunnel without interrupting the impoundment process, the LHDA has said.

The lower intake tunnel, which plays a vital role in the Polihali dam’s operational future, will facilitate the intake of live water even at low reservoir levels and is essential for ensuring the uninterrupted flow of water.

Key milestones in the Polihali transfer tunnel works include the excavation of the 450-m-long tunnel, which started on January 16 and was completed on August 19; the completion of the 370-m-long lower intake tunnel on August 5; and the ongoing excavation of the connecting tunnel.

The ship carrying the components of the first of the two tunnel boring machines (TBMs), which will excavate the Polihali-Katse transfer tunnel, berthed in the Port of Durban on August 27. The components were transported by road from Durban through the Free State reaching the Caledonspoort/Butha Buthe border post on September 5, where a small welcome ceremony was held. From there the vehicles made their way on the A1 to Hlotse, then through the A8/NAR toward Ha Lejone, and through Ha Lejone over the Malibamats’o river, and ultimately, to the Katse site at Ha Bereng where the TBM will be reassembled. 

The 1 322-m-long connecting tunnel will connect the TBM access adit at the chamber where the TBM will be assembled, marking the start of the TBM-bored transfer tunnel to Katse. To date, 26 m of the connecting tunnel have been completed.

Key Contracts, Suppliers and Consultants
To date, several contracts have been awarded for various elements of the main and advance infrastructure works. These include:

Contract 3004: Professional services for the planning, design and construction supervision of the PWAR.

The LHDA awarded the contract to AECOM SA, together with Lesotho-based subconsultants AECOM Lesotho and RWB Consulting Engineers, in October 2016. The tenders for the construction of the PWAR were advertised in the second quarter of 2018.

The PWAR west and the PWAR east contracts have been awarded to South African Hillary Construction, Polokwane Surfacing, Ya Rena Civils (HSPV) JV and Lesotho-based Structuretone Construction, and Rumdel/AC JV.

The PWAR west contractors include South Africa-based Hillary Construction, Polokwane Surfacing, Ya Rena Civils and Lesotho-based Structuretone Construction.

The PWAR east contractor, Rumdel/AC JV, comprises South Africa-based Rumdel Construction and Lesotho-based A&C Holdings.

The Northern Access Road rehabilitation tender has been awarded to the HSPV JV.

Contract 3006: Professional services for the design and construction supervision of the Polihali dam and appurtenant works.

The contract was awarded in June 2017 to Matla a Metsi JV. The partners are Mott MacDonald Africa (South Africa), GIBB (South Africa), Tractebel Engineering SA Coyne et Bellier (France) and LYMA Consulting Engineers (Lesotho).

Contract 3007: professional services for the design and construction supervision of the Polihali transfer tunnel.

The contract was awarded in December 2017 to the Metsi a Senqu Khubelu Consultants (MSKC) JV. The partners are Zutari South Africa, Hatch Africa, Knight Piésold, SMEC South Africa and Lesotho-based FM Associates.

Contract 3008: Professional services for the bulk power supply and telecommunications.
The contract was awarded in August 2016 to Plantech-SM JV.

The contract for the construction of a 132 kV power line from Matsoku to Polihali was awarded to South Africa-based Mkhulu Electro Distribution Projects in October 2019.

Contract 3009: Professional services for the planning, design and construction supervision of housing and associated infrastructure.

The contract was awarded in June 2015 to Polihali Infrastructure Consultants – a JV comprising South Africa-based engineering consultancy Mott MacDonald and Lesotho-based Khatleli Tomane Moteane.

The tender for the construction of the infrastructure civil works, including roads, water and wastewater systems, electricity and telecoms supply, was awarded to the Polihali JV in October 2018.

The contract for the construction of permanent housing at the Polihali Village was awarded to the Polihali Village JV in December 2021, following the JV’s work on the civil works and bulk utilities at Polihali and Katse, which were completed towards the end of 2021.

Contract 3010: Professional Services for the Phase II hydropower feasibility (further studies).
The contract was awarded in March 2017 to the EDF/GIBB/Multiconsult JV. The work has been completed.

Contract 3013: A light detection and ranging, or Lidar, survey and aerial photography of the Mohale and Katse reservoir areas, powerline corridor and the Polihali dam inundation area.
The contract was awarded in November 2017 to Southern Mapping Geospatial. The work has been completed.

Contract 3014: Professional services for the design and construction supervision of the Polihali north-east access road was awarded to the SMEC-FMA JV in April 2015.

Contract 3015: Professional services for the evaluation, optimisation and site supervision of geotechnical investigations.

The contract was awarded in May 2015 to consultant Jeffares & Green (now called JG Afrika) and Lesotho-based GWC Consulting Engineers. The contract has closed.

Contract 3017: Professional Services for the demarcation of the Polihali reservoir.
This entailed the construction of more than 1 300 beacons to mark the 230 km perimeter of the reservoir.

The contract was awarded in April 2015 to Lesotho-based consultancy Maleka, Ntshihlele, Putsoa JV.

The reservoir demarcation was completed in December 2015.

Contract 3020: Design and supervision of the construction of the major bridges to be built.
Zutari, formerly Aurecon Lesotho, was appointed to design and supervise the construction of the bridges. The project also includes the realignment of the A1 national road in the vicinity of the bridges. Lesotho-based White Life Consultants and Leporogo Specialist Engineers CC of South Africa are the subconsultants.

Zutari Lesotho has been awarded the professional services contract for the development of the master plan for feeder roads and bridges related to the LHWP Phase II.

Work on the contract is valued at about M13-million.

Zutari will work with other Lesotho-based firms and black-owned South African firms.

The development of the master feeder plan for the roads and bridges is part of the process to determine the infrastructure required to support post-construction public mobility around and across the Polihali reservoir, to be built under Phase II.

The feeder roads are intended to improve connectivity and access to villages that will be affected by the construction of the Polihali dam and reservoir inundation.

Another key activity under the contract is to identify viable options for all feeder roads and bridges that are required to connect villages to each other and the existing national road network.

Viable options will be prioritised based on the findings of the environmental- and social-impact assessment studies, to be completed as part of the feeder roads master plan development process, as will the lessons learned from Phase I regarding the mobility of communities around the reservoir.

Contract 3022: Professional services for the design and supervision of the Polihali diversion tunnels.

The contract was awarded in October 2016 to MSKC JV. The procurement of the contractors for the construction of the diversion tunnel started in the last quarter of 2017 and the tender closed in January 2018.

Contract 4005B: Construction of 33 kV line from Tlokoeng to Polihali and the relocation of the 33 kV line along the A1. Work was completed in June 2021.

The contract was awarded in February 2019 to LSP Construction. The subcontractors are Dihlase Consulting Engineers (South Africa), Van den Ende & Associates Consulting Engineers CC (South Africa), NC Nelson Projects (South Africa) and Fibre Based Integrations (South Africa).

Contract 4005C: The contract for the construction of the 132/33/11 kV substation at Polihali and the upgrade of the existing substation along the A1 was awarded to the CLM JV in February 2020. The JV partners are Consolidated Power Projects (South Africa), LSP Construction (Lesotho) and Mofomo Construction (South Africa). Both contracts have been completed and were energised in mid-January 2022.

Contract 4012: Construction of the Polihali north-east access road. The contract was awarded in October 2018 to the Sinohydro SA (South Africa) / Nthane Brothers (Lesotho) JV.

Contract 4016: Geotechnical investigation works for the Polihali dam and Polihali–Katse transfer tunnel.

The contract was awarded to geotechnical drilling company Diabor in November 2015. The investigations were completed in two stages – the first in May 2017 and the second in May 2019.

Contract 4018E: Katse Village upgrades, which has been awarded to Lesotho-based Unik Construction Engineering.

Contract 4019A: Senqu river bridge has been awarded to the WRES Senqu Bridge JV, which comprises Italy-based Webuild; South African firms Raubex Construction and Enza Construction and Lesotho-based Sigma Construction. Subcontractors include South African firms EXR Construction and Post Tensioning and Structural Solutions; Austria’s Gleitbau-Geselschaft; and France-based Freyssinet International et Cie.

Contract 4019B: The Mabunyaneng river bridge and the Khubelu river bridges contract was awarded in August 2023.

Concor-Nthane Brothers M&K Bridges JV. The JV comprises main partners Concor Construction (South Africa) and Nthane Brothers (Lesotho), as well as sub-contractors Post Tensioning and Structural Solutions (South Africa) and Bridge Joints and Rehabilitation Contractors (Lesotho).

Contract 4020: SUN JV (construction contract), which includes main partners: Sinohydro Bureau 8 (China); Sinohydro Bureau 14 (China); Unik Civil Engineering (South Africa) and Nthane Brothers (Lesotho). Subcontractors include Melki Civils and Plant Hire (South Africa); MECSA Construction (South Africa); SIGMA Construction (Lesotho) and Kunming Engineering (China).

Contract 4021: KKM JV (construction contract), which includes main partners: Yellow River (China); Sinohydro Bureau 3 (China); Unik Civil Engineering (South Africa). Subcontractors include Esor Construction (South Africa); MECSA Construction (South Africa); Nthane Brothers (Lesotho); Sinohydro Bureau 6 (China); Fugro Middle East (United Arab Emirates). 

Contract 4022: SCLC Polihali Diversion Tunnel JV, which comprises Webuild (formerly Salini Impregilo), Cooperativa Muratori Cementistri CMC di Ravenna, LSP Construction and CMI Infrastructure, is constructing the tunnels, while the M MSKC JV has designed the diversion tunnels and is supervising construction. It includes Africa- and Lesotho-based firms Zutari, FM Associates, Knight Piésold, Hatch Goba and SMEC. Construction was completed in November 2021. The contractor and consultant have demobilised from site and the one-year defects notification period started on November 26, 2021.

Contract 4023: Design, supply and installation of temporary offices and accommodation units.

The contract was awarded in August 2018 to the Senqu-Hi-Way JV. The JV partners are Senqu Construction Services (Lesotho), Hi-Way Parkhome and Container Services (South Africa). Subcontractor: Electromech Engineering Solutions. Work under this contract has been completed.

Contract 6004: Professional services for the environmental- and social-impact assessment (ESIA) for the Polihali western access corridor (PWAC).

The contract was awarded in October 2016 to a JV comprising Environmental Resources Management (ERM) Southern Africa and Lesotho-based Sechaba Consultants. In March 2018, the Lesotho Ministry of Tourism, Environment and Culture issued the LHDA with a record of decision comprising environmental authorisation for the proposed PWAC, following the completion of the PWAC ESIA and the associated environmental management plan, effectively granting environmental authorisation to proceed with the PWAC construction activities.

Contract 6006: Professional services for resettlement planning and implementation: PWAC.

The contract was awarded in October 2016 to Makhetha Development Consultants. The subconsultants are Lesotho-based Senqu Engineering and Development Consultants, Motheo Holdings, Survey and Digital Mapping, Advocate Thato Kao (Lesotho), Puisano HIV/AIDS Training & Support Services and South African company Setplan.

Contract 6010: Professional services for the development of a Phase II safety, environment and quality management framework.

The contract was awarded in September 2016 to Rori Management Consultancy.

Contract 6014: Professional services for the ESIA for the Polihali reservoir and associated infrastructure.

The contract was awarded in August 2016 to a JV comprising ERM Southern Africa (South Africa) and Lesotho-based Sechaba Consultants (Lesotho).

Contract 6015: Professional services for the resettlement planning and implementation of the Polihali site establishment and reservoir area.

The contract was awarded to the LIMA Thaha JV in September 2016.

Contract 6023: Professional services for the safety, health, environment and quality management audits for the Phase II advance infrastructure works.

The contract was awarded in October 2018 to GA Environment (South Africa).

Contract 6025: Professional services for the development and implementation of a cultural heritage plan. The contract was awarded to PGS Heritage in December 2017.

Contract 9004: Professional services pertaining to principal controlled insurance. The contract was awarded to Minet in November 2017.

Contact Details for Project Information
LHDA, public relations, tel +266 2224600 or email brownm@lhda.org.ls or lhwp@lhda.org.ls