As South Africa’s population grows, the strain on our water supply becomes increasingly apparent, particularly in urban centres like Johannesburg. One-fifth of the country’s population relies on water from the Lesotho Highlands Water Project (LHWP), a crucial system that transports water from the mountains of Lesotho into South Africa. However, this lifeline is under threat, facing numerous environmental challenges that could severely compromise its long-term viability.
This blog draws on information from a detailed article by GroundUp, authored by Sean Christie, titled “Follow the Water: Tracing Lesotho’s Uncertain Water Supply for Johannesburg”, which provides a sobering account of the state of water resources in Lesotho. Christie’s exploration into the LHWP reveals how degradation of wetlands and poor land management are accelerating the decline of this vital water system.
At the heart of the project is the Katse Dam, the largest reservoir in the LHWP, fed by the Malibamatso and Bokong rivers. These rivers, essential to Johannesburg’s water supply, are becoming increasingly unpredictable due to the destruction of Lesotho’s wetlands. Historically, these wetlands acted as natural sponges, slowing down the flow of water and trapping sediment, which helps prevent topsoil erosion. Today, they are failing. Overgrazing, poor agricultural practices, and climate change have all taken a toll on these critical ecosystems.
Lesotho’s valley-bottom peatlands, which once retained water and stabilised river flows, are now rapidly degrading. Erosion channels have begun to form, speeding up water flow and causing significant sediment build-up in the Katse and Mohale dams. According to the Lesotho Highlands Development Authority, this sedimentation is a growing concern, with silt reducing the dams’ capacities and threatening the reliability of water delivery to South Africa.
This decline in the health of Lesotho’s wetlands is not only an environmental crisis but also a socio-economic one. Ironically, many of the communities relocated to make way for the construction of these dams still struggle with access to clean water. Despite living near vast reservoirs, rural communities in Lesotho face significant water shortages, with over 30% lacking adequate water services, according to WaterAid. This paradox highlights the complexity of managing water resources across borders while balancing local and national needs.
Overgrazing in the Lesotho highlands further exacerbates the problem. Livestock owners, who once rotated their herds seasonally, now graze their animals year-round, preventing the natural recovery of vegetation. This has led to increased soil erosion, as the landscape is stripped bare. Nearly 70% of Lesotho’s highland wetlands are affected by overgrazing, significantly accelerating their degradation. Without immediate action, these vital ecosystems will continue to deteriorate, placing Johannesburg’s water supply at even greater risk.
The LHWP’s next major project, the Polihali Dam, is expected to be completed by 2028 and will become the largest water supplier to South Africa’s urban highveld. But questions about the sustainability of this system persist. Without a concerted effort to rehabilitate the wetlands and address the issue of overgrazing, the Polihali Dam, like its predecessors, could face severe sedimentation problems.
The urgency of this issue cannot be overstated. Johannesburg, already facing significant water challenges, could be headed towards a “Day Zero” scenario—a point where water becomes unavailable to residents—unless measures are taken to protect Lesotho’s water catchments. As highlighted by GroundUp, conserving these wetlands and implementing sustainable land management practices is not just a local concern but a critical regional issue.
In fact, Johannesburg’s director-general of water, Sean Phillips, has warned that the city is using water unsustainably. The looming threat of a “Day Zero” event is real, and the city’s dependence on the Lesotho Highlands Water Project only compounds this risk. If Lesotho’s wetlands continue to degrade and sediment continues to build in its reservoirs, Johannesburg could soon face the dire consequences of water scarcity.
The health of the LHWP is intrinsically linked to the environmental well-being of Lesotho’s highlands. The wetlands, rivers, and dams in this region are not only critical to South Africa’s water security but also to the livelihoods of Lesotho’s rural communities. It is imperative that South Africa and Lesotho work together to restore these ecosystems and implement sustainable practices that can secure water resources for future generations.
In conclusion, the long-term sustainability of Johannesburg’s water supply hinges on the protection and restoration of Lesotho’s wetlands. Without urgent, collaborative action from both nations, the Lesotho Highlands Water Project’s capacity to meet demand could diminish, leading to devastating consequences for millions of people in both countries.
For a more in-depth look at the challenges facing the Lesotho Highlands Water Project, we encourage readers to explore Sean Christie’s original article on GroundUp: “Follow the Water: Tracing Lesotho’s Uncertain Water Supply for Johannesburg”. His reporting offers critical insights into the complex environmental and social dynamics at play in this region.
By understanding the fragility of this water system, we can push for the necessary changes to ensure a sustainable future for South Africa’s water supply.