Lesotho: Tackling water insecurity in a changing climate

The document analyzes the trade-offs between Lesotho's water exports via the Lesotho Highlands Water Project (LHWP) and its domestic needs for water, agriculture, and industry. Using the Water Evaluation and Planning (WEAP) system, it finds that while climate change introduces uncertainty in precipitation, strategic investments in the Polihali Dam and the Lesotho Lowlands Water Supply Scheme (LLWSS) can simultaneously secure water transfers to South Africa and improve domestic water and food security.

• Water is a critical economic driver for Lesotho, with the water sector contributing approximately 8–10% to the national GDP. The Lesotho Highlands Water Project (LHWP) specifically accounts for about 3% of GDP, having generated nearly US$800 million in revenues since 1996 and facilitating investments exceeding US$3 billion.
• Lesotho faces significant water insecurity due to natural climatic variations and inadequate infrastructure. The country is vulnerable to extreme events, including the largest floods since the 1930s in 2011 and the most severe drought on record during 2015–16.
• Climate modeling for the period 2041–2050 indicates a consistent rise in average mean surface air temperatures between 0.8°C and 2.9°C. However, precipitation projections are highly variable, with 64 scenarios predicting drier conditions and 57 predicting wetter conditions, ranging from a 20% decrease to a 20% increase relative to the historical average of 760 mm.
• Without further infrastructure development, Lesotho's domestic and industrial sectors will face significant water deficits, with over half of the projections showing shortages exceeding 15% of demand by 2050. Additionally, meeting water delivery commitments to South Africa would become increasingly difficult, with transfer deficits occurring in 49% of climate scenarios between 2041 and 2050.
• The construction of the Polihali Dam under Phase 2 of the LHWP is identified as a key measure to reduce the risk of failing to meet water delivery commitments to South Africa, lowering the occurrence of transfer deficits to 13% of climate scenarios.
• Implementing the Lesotho Lowlands Water Supply Scheme (LLWSS) would enhance the resilience of the domestic sector by reducing unmet demand without jeopardizing the reliability of water transfers to South Africa.
• Expanding irrigation by 12,000 hectares could increase the production of maize, beans, peas, sorghum, and wheat by 70,000 to over 100,000 tonnes per year, representing a potential increase of up to 50% over current rainfed production.

APA

Huber-Lee, A., Galaitsi, S., Davis, M., Wishart, M., & Emenanjo, I. (2016). Lesotho: Tackling water insecurity in a changing climate. Stockholm Environment Institute. https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WB-PB-2016-Lesotho-water-climate.pdf

Chicago

Huber-Lee, Annette, Stephanie Galaitsi, Marion Davis, Marcus Wishart, and Ijeoma Emenanjo. Lesotho: Tackling water insecurity in a changing climate. Stockholm Environment Institute, 2016. https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WB-PB-2016-Lesotho-water-climate.pdf.

Wikipedia

{{cite report |last1=Huber-Lee |first1=Annette |last2=Galaitsi |first2=Stephanie |last3=Davis |first3=Marion |last4=Wishart |first4=Marcus |last5=Emenanjo |first5=Ijeoma |title=Lesotho: Tackling water insecurity in a changing climate |publisher=Stockholm Environment Institute |date=2016 |url=https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WB-PB-2016-Lesotho-water-climate.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{huberlee2016lesotho, author = {Huber-Lee, Annette and Galaitsi, Stephanie and Davis, Marion and Wishart, Marcus and Emenanjo, Ijeoma}, title = {{Lesotho: Tackling water insecurity in a changing climate}}, institution = {Stockholm Environment Institute}, year = {2016}, url = {https://www.sei.org/mediamanager/documents/Publications/Climate/SEI-WB-PB-2016-Lesotho-water-climate.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }