The Lesotho Highlands Development Authority (LHDA) has launched a tender for the construction of the Polihali transfer tunnel, which is part of phase II of the Lesotho Highlands Water Project. The tunnel will have a length of 38 kilometers and a 5-meter diameter. 

The scope of works will include the tunnel boring and drill and blast methods to excavate the tunnel. The project will transfer water by gravity from the under-development Polihali Dam reservoir to the Katse reservoir, built in phase I. From there, the water travels through its own transfer tunnel to generate electricity at the Muela hydropower plant before entering the Gauteng region of South Africa.

The new tunnel together with the dam will increase the flow of water from Katse to Gauteng to 1.27 billion cubic meters per year, compare to 780 million cubic meters, and will also improve electricity generation. 

A contract for the design and construction supervision of the project has been awarded to a joint venture of FM Associates and Zutari, Hatch Africa, Knight Piesold and SMEC South Africa.

The deadline to submit the response is August 30, 2021. More information about this opportunity can be found here.