The Polihali Dam project in Lesotho’s highlands is progressing after years of delays, with approximately 30% of the main work completed. The dam, part of the Lesotho Highlands Water Project’s Phase II, aims to boost the water supply to South Africa’s Gauteng region. By the end of July 2025, around R18-billion of the R53-billion budget had been spent, according to the Lesotho Highlands Development Authority.
The Polihali Dam will create a reservoir covering over 5,000 hectares, holding 2,325-million cubic meters of water. Upon completion, it is expected to increase annual water transfers to Gauteng from 780 to 1,270-million cubic meters and raise electricity production at Lesotho’s ‘Muela hydropower plant from 500GWh to 800GWh per year. The project has created jobs for roughly 14,000 people, although it is unlikely to significantly reduce Lesotho’s 30% unemployment rate.
The development has had a significant impact on the local community, with over 7,200 community assets expropriated and M154-million paid in compensation for nearly 5,600 of them. However, delays in outstanding payments have been reported, often due to identification and ownership documentation problems, family disputes, or the absence of bank accounts.
Environmental concerns have also been raised, with communities lodging complaints about dust, noise, air pollution, and water quality. Contractors have generated significant amounts of waste, including 20,500 liters of waste oil, nearly 9,000 kilograms of hazardous waste, and over 34,000 cubic meters of wastewater. While 40 environmental incidents have been reported, none are considered significant, and project supervisors are monitoring these reports.
The construction of three major bridges, including the Senqu Bridge, is underway to maintain road access across the reservoir. The Senqu Bridge, the largest and most complex, is expected to be completed in February next year, after initial delays caused by design changes, operational problems, and labor strikes. Work is also progressing on the 38-kilometer transfer tunnel that will connect Polihali to the Katse Dam, allowing for increased water transfers to South Africa.
The project’s completion is now expected between August and September 2029, with water impoundment scheduled for November 2026. The Polihali Dam’s significance lies in its potential to boost water security and electricity production in the region, making it a crucial infrastructure development for both Lesotho and South Africa. As construction continues, the project’s impact on the local community and environment will remain a key focus area for the developers and authorities involved.
