The Lesotho Electricity Company (LEC) predicts that the completion of the second phase of the Lesotho Highlands Development Authority (LHDA) will likely force a decline to electricity prices.
According to the LEC Public Relations Manager Makhetha Motšoari, Lesotho is going to greatly cut down on electricity supply imports from foreign power utilities Eskom from the neighbouring South Africa and EDM from Mozambique.
He pointed out that currently Lesotho needs about 170megawatts of electricity in order to cover its national power needs, adding that 72megawatts is generated from the ‘Muela Hydropower Station with the remaining 98megawatts imported from EDM and Eskom.
A statement released by the LHDA this week indicates that phase two will augment the national electricity supply in a move that will see the country’s dependency on imports greatly thwarted.
“It will increase the quantity of electricity generated at the ‘Muela hydropower station from approximately 500GWh to 800GWh per year and is a further step in the process of securing an independent electricity source to meet Lesotho’s domestic requirements. The hydropower further feasibility studies confirmed that conventional hydropower is the preferred option for the Phase II hydropower component and identified three potential sites,” the release reads.
“If the project at Polihali helps it also means that we will no longer have to buy electricity outside the country but will give priority to the local companies and projects. This also means that the electricity will become cheaper to the local clients,” Motšoari said.
Earlier this week LHDA announced that the construction workers and representatives of the supervising engineers and the construction contractor celebrated a significant milestone in their construction of Phase II of the Lesotho Highlands Water Project (LHWP) with the completion of two diversion tunnels.
It is reported that the tunnels; one 7m in diameter, the other 9m in diameter and both almost a kilometre long, were excavated by both drill and blast method and achieved the breakthrough on the same day and at almost the same time this week, some four months ahead of estimated time for completion.
According to LHDA, the diversion tunnels will convey water that is diverted away from its natural path (the river) to ensure that during construction of the Polihali Dam, work can take place in a dry area, uninterrupted by the river flow. The LHDA advanced the construction of these diversion tunnels to enable the dam contractor once appointed, to immediately focus on diverting the river through the tunnels instead of the traditional approach of incorporating the diversion tunnels works as part of the dam construction scope. As a result, the dam contractor will also have earlier access to the river section than normal.
The diversion tunnels construction contract was awarded in February 2019 and its completion was slated for end of this year (2021).
Phase II of the Lesotho Highlands Water Project follows the successful completion of Phase I in 2003. LHDA said the project delivers water to the Gauteng region of South Africa and utilizes the water delivery system to generate electricity for Lesotho. Phase II will increase the current water transfer rate of 780 million cubic metres per annum incrementally to more than 1 270 million cubic metres per annum.
The contractor, the SCLC-JV, which comprises the South African Salini Impregilo S.p.A, Cooperativa Muratori Cementistri CMC di Ravenna (South African branch), Lesotho-based LSP Construction (Pty) Ltd and South African CMI Infrastructure Ltd is constructing the tunnels under the supervision of the Metsi a Senqu-Khubelu Consultants Joint Venture (MSKC-JV) which also designed the diversion tunnels.
On the same note, the supervising Engineer, MSKC also includes a number of South African and Lesotho-based firms viz. Zutari (SA), Hatch Goba (SA), Knight Piesold (SA), SMEC (SA), and FM Associates (LSO), S5 Construction Consultants (LSO), White Life Consultants (LSO).
LHDA Phase II Contracts Manager, Thabo Hloele confirmed that “…the breakthrough marks the completion of 1870 meters of the tunnel excavation and is a significant step in Phase II construction,”.
While SCLC-JV contractor’s representative Mr Paolo Campanella, stated that the completion of the tunnels is an enormous step as they soldiered through the cold storms and the ravaging Covid-19 pandemic.
“The breakthrough is a significant milestone for the team that has been tunnelling on this project for the past fourteen months. It celebrates progress achieved despite challenges such as the COVID-19 pandemic, harsh weather conditions, flooding of the Senqu River which affected the construction site in January 2021 and other social challenges,” Campanella said.
According to LHDA, the excavation inside the two Polihali diversion tunnels commenced in June 2020 and mostly advanced from the outlets. Completed works on the contract include excavation of the portals and the in-situ reinforced concrete lining of inside walls of the two tunnels for approximately 35m from the entrance of both tunnels. On-going works include finalisation of construction of the concrete intake structure on the 9m diameter tunnel. Construction of the intake structure on the ancillary 7m diameter tunnel is almost complete. The remaining works include invert concrete lining for the overall lengths of the tunnels and some minor surface works.
The Resident Engineer, Ntsoeleng Mohale also from MSKC-JV, who designed the tunnels and led the construction supervision, said the breakthrough is a long-awaited event which marks the end of the critical stage of tunnelling.
“We are proud of the double breakthrough we celebrated on Monday. It has been a long and challenging journey to get here but we made it thanks to the expertise and dedication of many people. For some of us this is one of the biggest milestones of our careers, while for the young professionals, the project has provided an invaluable experience in tunnelling,” he said.
According to Mohale, who is also a product of the LHDA’s “on-the-job training” programme which jump started engineering careers for young professionals during the first phase of the Lesotho Highlands Water Project, understanding the value of his own experience underpins his passion for mentoring the young engineers currently working on the diversion tunnels project under the LHWP Phase II Young Professionals Programme.
“We have seen these young engineers move from training to performance level and I’m proud that they contributed immensely towards the breakthrough. The exposure and experience gained on this contract will increase their marketability in the job market,” he said.
While a young Civil Engineering technologist, Sechaba Mokhali expressed his gratitude for the mentorship program which he lauded as a “…mentorship of a team of experts in various facets of project management and the unique tunnelling construction experience I have gained. The LHDA young professionals’ mentorship programme is contributing to an innovative generation of engineers that have to come up with solutions to tackle the challenges facing society today,”.