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Lesotho Highlands Water Project – Phase II, Lesotho and South Africa

19th January 2018

By: Sheila Barradas

Creamer Media Research Coordinator & Senior Deputy Editor

     

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

Location
Lesotho and South Africa.

Client
The Lesotho Highlands Development Authority (LHDA) and the Trans-Caledon Tunnel Authority (TCTA) are the implementing authorities.

The Lesotho Highlands Water Commission has an oversight function, and represents and advises the two governments, as well as monitors the activities of the LHDA and the TCTA.

Project Description
Phase 2 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 for Lesotho.

Phase 2 will increase the current supply rate of 780-million cubic metres a year incrementally to more than 1.26-billion cubic metres a year.

Phase II of the LHWP will be implemented in terms of 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 will be constructed as a concrete-faced rockfill embankment with a side channel spillway about 164 m high.
The crest length will be about 915 m, with a full supply level of 2 075 m above sea level. A 50-m-high saddle dam will also be built.

Polihali to Katse tunnel
An 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.

Water will be abstracted from the Polihali reservoir through two separate concrete bell-mouth intakes on the western side of the Polihali reservoir, in the Khubelu river, 3 km upstream of the confluence with the Senqu.

Water will be transferred through the lower and upper intake tunnels to the intake gate shaft. Both tunnels will be constructed using drill-and-blast methods and will be fully concrete-lined. Hydraulic control will be effected by the valves in the intake structures.

The Polihali intake gate shaft will be used only for maintenance and water quality control functions.

Advance infrastructure
Phase II will require extensive infrastructure development before the mobilisation of contractors for the two main works contracts of the Polihali dam and transfer tunnel. Where possible, the existing infrastructure constructed in Phase I will be used. This includes access roads, power supply, telecommunication systems and camps.

Significant additional works contracts will be awarded for the construction of all-weather access roads, a bulk power supply network, telecommunications systems and project housing, as well as labour camps on both ends of the transfer tunnel.

A permanent housing development will be established near the Polihali dam and transfer tunnel, which will consist of project offices, and residential and community facilities.

The Polihali intake site will use the infrastructure employed to construct the Polihali dam and the 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. Existing accommodation facilities will be used to house consultants and construction management teams. Improvements to the water and sewage treatment plants, clinic and lodge will also be undertaken.

Other infrastructure
In addition to the main access roads to service the construction phase, other access and feeder roads will be built around the reservoir to connect affected communities using pedestrian and light-vehicle bridges, while a pair of major road bridges will be built over the Polihali reservoir, at Mapholaneng, crossing the Khubelu river, and near Mokhotlong, crossing the Senqu river.

Environmental measures
An environmental and social management programme is being implemented to address potential environmental and social impacts associated with Phase II activities.

The programme comprises baseline studies completed in 2013 and 2014, including studies pertaining to environmental flow requirements, and biological and archaeological (including heritage) aspects, as well as socioeconomic and public health studies. It also includes environmental- and social-impact assessments (ESIAs), and the implementation of the subsequent environmental and social management and action plans. These are in progress.

Social development programmes
These programmes, mitigation measures, resettlement requirements and baseline studies, as well as public relations/community engagement and awareness campaigns, will be implemented.

The full extent of these measures is being studied and discussed.

The design of these programmes is being informed by the outcome of the baseline studies. The resultant sustainable development programmes to be designed and implemented will be agreed on with the affected communities.

Pumped-storage scheme
The Phase II agreement on the LHWP  determined that the hydropower generation component will comprise the Kobong pumped-storage scheme  or any other similar scheme subject to agreement on the outcome of further feasibility studies.

These should include a market study, an integration study, geotechnical investigations, and legal and commercial arrangements. The additional feasibility studies will explore alternative viable hydropower generation schemes that will increase the electricity generation capacity in Lesotho, which will assist in meeting the country’s electricity requirements.

These further feasibility studies are under way to determine the way forward. The studies started towards the end of 2016 and are expected to be completed by the end of 2017.  The contract was awarded to EDF Hydro Engineering with GIBB, Multiconsult UK and Lesotho-based LYMA.

Jobs to be Created
Based on what transpired during the implementation of Phase I of the project, more than 3 000 jobs are expected to be created at the height of the construction phase of the main works of Phase II.

Value
As of November 2015, the cost of the Phase II water transfer component at the date of project completion in 2025 was estimated at R22.9-billion. The cost of the hydropower component is yet to be established.

Duration
The development has been materially delayed; completion, initially slated for 2020, is now expected in 2025, based on the current project programme.

Latest Developments
The LHDA has awarded the contract for designing and supervising the construction of the Polihali water transfer tunnel, the largest of all the Phase II engineering design contracts, to the Metsi a Senqu-Khubelu Consultants (MSKC) joint venture.  Work on the estimated M/R900-million design and construction supervision contract started in December 2017.
  
MSKC comprises Lesotho-based FM Associates, and South African firms Aurecon South Africa, Hatch Africa, Knight Piesold and SMEC South Africa. Sub-consultants include White Life Consultants, Lesotho; S5 Construction Consultants, Lesotho; and ILISO Consulting, South Africa. 
 
The consultants’ scope of services includes reviewing the existing project information and preparing the preliminary design of the transfer tunnel; preparing the tender design for the construction of the tunnel, tender drawings and tender documents; supporting the LHDA through the contractor tender and contract award process, preparing construction design and drawings, and offering contract management services during the construction of the tunnel. 
 
Training LHDA staff to operate and maintain the tunnel is part of the skills and technology transfer element. The project also makes provision for the training of young professionals. 
 
The envisaged transfer tunnel will be about 38 km long, with a nominal bore of 5 m. It will transfer water by gravity from Phase II’s Polihali reservoir, in the Mokhotlong district, into the Katse reservoir for eventual delivery to South Africa through the existing transfer scheme. Construction of the tunnel is expected to start in 2020 and be completed by the end of 2025. Tunnel boring and drill-and-blast methods will be used to excavate the tunnel.
 
Key Contracts and Suppliers
To date, several contracts have been awarded for various elements of the advance infrastructure works. These include:

Contract 3004: Professional services for the planning, design and construction supervision of the Polihali western access road.
The LHDA awarded the contract to AECOM SA, together with Lesotho-based subconsultants AECOM Lesotho and RWB Consulting Engineers in August 2016.

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

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.

Contract 3014: Professional services for the design and construction supervision of the Polihali north-east access road.
The contract was awarded in April 2015 to SMEC-FMA JV, comprising the Bloemfontein branch of international engineering consultancy SMEC and Lesotho-based civil engineering firm FM Associates.

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.

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 the Maleka, Ntshihlele, Putsoa JV. The reservoir demarcation was completed in December 2015.

Contract 3022: Professional Services for the design and supervision of the Polihali diversion tunnels.
The contract was awarded in October 2016 to Metsi a Senqu-Khubelu Consultants 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.

Contract 6004: Professional services for the environmental and social-impact assessment for the Polihali western access corridor.
The contract was awarded in October 2016 to a JV comprising the Environmental Resources Management (ERM) Southern Africa and Lesotho-based Sechaba Consultants.

Contract 6010: Professional services for the development of a Phase II safety, environment and quality management framework.
The contract was awarded in October 2016 to Rori Management Consultancy.

Contract 6014: Professional services for the environmental- and social-impact assessment for the Polihali reservoir and associated infrastructure.
The contract was awarded in August 2016 to a JV comprising ERM Southern Africa and Lesotho-based Sechaba Consultants.

Contract  6015: Professional services for the resettlement planning and implementation: Polihali site establishment and reservoir area.
The contract was awarded to the LIMA Thaha JV in September 2016.

The advance infrastructure will be largely completed before the start of the main works in 2020.  Twenty advance infrastructure construction contracts across many disciplines, including roads, bridges, housing, power and water supply, and waste management, will go out to tender from the last quarter of 2017.  Their values will range from R/M1-million to more than R/M1-billion each.

On Budget and on Time?
Water delivery is expected to begin in 2025 based on the current project programme. It is too early to comment on the hydropower component, as its exact form is still to be determined by the ongoing feasibility studies.

Contact Details for Project Information
LHDA responsible manager – divisional manager Phase II Tente Tente, tel +266 222 46000 or email tentet@lhda.org.ls.
LHDA Public Relations Manager Masilo Phakoe, tel +266 62857272 or email phakoem@lhda.org.ls.

Edited by Creamer Media Reporter

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