Two more advance infrastructure construction tenders for Phase II of the Lesotho Highlands Water Project (LHWP) have been advertised, with construction expected to start next year.

Phase II comprises a wide range of small and large contracts, and Lesotho Highlands Development Authority (LHDA) divisional manager of Phase II Tente Tente says several more tenders will be advertised between now and mid-2019.

Deadlines for submissions for Contract 4022, for the construction of the Polihali diversion tunnels, and for Contract 4018A, for the construction of advance infrastructure civil works at Polihali and Katse, are set for January 10 and 12 respectively.

The two diversion tunnels to be constructed under Contract 4022, will divert the waters of the Senqu river away from the Polihali dam construction site. Tente explains that the tunnels will be excavated through the left flank, upstream of the dam site, prior to the main dam construction contract to minimise flooding of the dam foundation works. He stresses that this approach reduces the risk of delays to the construction programme for the dam.

The advance infrastructure civil works include the construction of the civil works and utilities to service permanent and temporary facilities at the Polihali and Katse villages.

Tente notes that, at Polihali, the scope comprises earthworks and the creation of platforms, water and wastewater systems, landfill sites, roads and drainage, as well as electrical and telecommunications networks. “At Katse village, the works cover the upgrade of existing water and wastewater systems, landfill, roads and utilities.”

He comments that, according to the current project master programme, construction of the tunnels is expected to start in May 2018 and to be completed in October 2019. Additionally, construction of the civil works is expected to start in June 2018 and to be completed in April 2020.

“To date, three of the estimated 20 construction contracts have been advertised, signalling the start of the construction phase of the LHWP Phase II in 2018,” states Tente.

The third contract, as reported in Engineering News in October, entails the construction of the Polihali north-east access road. The tender was advertised at the end of September and bids have to be submitted by December 17.

The LHDA states that preference will be given to Lesotho nationals, South African nationals, professionals from the Southern African Development Community region and then international bidders, subject to conditions on quality, competitiveness, transparency and cost effectiveness being met.

The majority of the advance infrastructure components have to be completed before the construction of the main Phase II works can start.

Tente notes that the water transfer component of Phase II of the LHWP is estimated to cost R23-billion on completion in 2025. The project also entails a hydropower component, the cost of which is yet to be established.

Phase II builds on the 2003 completion of Phase I, which supplies water to Gauteng and uses the water delivery system to generate hydroelectricity for Lesotho, and will increase the current supply rate of 780-million cubic metres a year incrementally to more than 1.26-billion cubic metres a year.