Impacts of Dams on Downstream Riparian Ecosystems’ Health and Community Livelihoods: A Case of the Lesotho Highlands Water Project

  • Patrick Gwimbi
  • Thabo E. Rakuoane
Part of the Climate Change Management book series (CCM)


Environmental and social impact assessments and reviews for the Lesotho Highlands Water Project (LHWP) dams were completed and approved, thus providing rationale for the construction of the dams. However, little is known about the downstream effects of the dams on river flow regulations and riparian ecosystems’ health and subsequent impact on river-dependent communities’ livelihoods. This study assessed the impacts of Phase 1 LHWP on downstream river flow regulation and riparian ecosystems’ health and their subsequent impacts on river-dependent community livelihoods. The methodology included a review of secondary data and primary data derived from a questionnaire administered to a case study community. Data sets included in-stream flow requirements (IFR), riparian vegetation and responses of river-dependent communities on the impact of dams on their livelihoods. Construction of LHWP dams resulted in modification of the flow pattern of downstream rivers and overall condition of the riparian ecosystems. Excessive livestock grazing also caused extensive riparian zone degradation and soil erosion, thereby threatening people’s livelihoods. The riparian zone was characterized by loss of bushes and grass and invasion of the channel sloughs by woody vegetation. Community members downstream of LHWP dams reported experiencing reduction in fish populations in rivers, grass for thatching and crafts making, wild fruits, livestock grazing pastures, food sources, medicinal plants and timber. Livestock overgrazing was, however, also identified as significantly contributing to riparian ecosystems’ degradation long before the construction of the LHWP. The study concluded that reduced flows downstream of dams represent an escalating problem on riparian ecosystems’ health, threatening livelihood sources of river-dependent communities. This review is relevant in understanding of the linkages between dams, downstream river flow and its effects on riparian ecosystems’ health and subsequent impact on river-dependent community livelihoods. The paper concludes with recommendations for improving the integration of environmental flow considerations into riparian ecosystems’ management to sustain livelihoods of local communities.


Lesotho Highlands Water Project (LHWP) IFR policy Downstream Riparian ecosystems’ health Livelihoods 


  1. Alldredge B, Moore G (2012) Assessment of riparian vegetation sensitivity to river hydrology downstream of a major Texas dam. River Res Applic 30:230–244CrossRefGoogle Scholar
  2. Backeus I, Grab S (1995) Mires in Lesotho. Gunneria 70:243–250Google Scholar
  3. Boelhouwers JC, Sumner PD (2003) The palaeo environmental significance of southern African block fields and blockstreams. In: Phillips M, Springman SM, Arenson LU (eds) Permafrost. Swets & Zeitlinger, Lisse, pp 73–78. ISBN 90 5809 582 7Google Scholar
  4. Bouwes N, Weber N, Jordan CE, Saunders WC, Tattam IA, Volk C, Wheaton JM, Pollock MM (2016) Ecosystem experiment reveals benefits of natural and simulated beaver dams to a threatened population of steelhead (Oncorhynchus mykiss). Sci Rep 6:28581CrossRefGoogle Scholar
  5. Brown C (2008) Let it flow: reducing the environmental legacy of dams. Int Rivers 23(2):6Google Scholar
  6. Brown C, King J (2012) Modifying dam operating rules to deliver environmental flows: experiences from southern Africa. Int J River Basin Manag 10:13. Scholar
  7. Chakela QK (ed) (2014) The Lesotho national conference on sustainable land management. Book of Proceedings, Ministry of Forestry and Land Reclamation, MaseruGoogle Scholar
  8. Devitt P, Hitchcock RK (2010) Who drives resettlement? The case of Lesotho’s Mohale Dam. Afr Stud Monogr 31(2):57–106Google Scholar
  9. Divine OA, Michael S, Bridgette F, Henrietta A (2017) Environmental and socioeconomic perturbations of a dam project on catchment communities, Ghana. Glob Environ Health Saf 1(2):13Google Scholar
  10. Du Preez PJ, Brown LR (2010) Impact of domestic animals on ecosystem integrity of Lesotho high altitude peatlands. In: Grillo O (ed) Ecosystems biodiversity. Janeza Trdine 9, 51000 Rijeka, Croatia. ISBN: 978-953-307-417-7Google Scholar
  11. Duvail S, Hamerlynck O (2003) Mitigation of negative ecological and socio-economic impacts of the Diama dam on the Senegal River Delta wetland (Mauritania), using a model based decision support system. Hydrol Earth Syst Sci 7(1):133–146CrossRefGoogle Scholar
  12. Ford AES, Graham H, White PCL (2015) Integrating human and ecosystem health through ecosystem services frameworks. EcoHealth 12:660–671. Scholar
  13. Fu B, Li Y, Wang Y, Campbell A, Zhang B, Yin S, Zhu H, Xing Z, Jin X (2017) Evaluation of riparian condition of Songhua River by integration of remote sensing and field measurements. Sci Rep 7, 2565.
  14. Grobbelaar JU, Stegmann P (1987) Limnological characteristics, water quality and conservation measures of a high altitude bog and rivers in the Maluti Mountains, Lesotho. Water SA, Vol. 13(3)Google Scholar
  15. Grundling P, Linström A, Fokkema W, Grootjans AP (2015) Mires in the Maluti Mountains of Lesotho. Mires Peat 15:1–11Google Scholar
  16. Hardin G (1968) Tragedy of the commons. Science 162:1243–1248CrossRefGoogle Scholar
  17. Hitchcock RK (2015) The Lesotho Highlands Water Project: dams, development, and the world bank. Soc Anthropol 3(10):526–538. Scholar
  18. Hoover R (2001) Pipe dreams: the world bank’s failed efforts to restore lives and livelihoods of dam-affected people in Lesotho. International Rivers Network, BerkeleyGoogle Scholar
  19. James CS, Mackay SJ, Arthington AH, Capon SJ, Barnes A, Pearso B (2016) Does stream flow structure woody riparian vegetation in subtropical catchments? Ecol Evol 6(16):5950–5963CrossRefGoogle Scholar
  20. Jay G, Xi-lai L, Brierley G, Cheung A, Yang Y-w (2013) Geomorphic-centered classification of wetlands on the Qinghai-Tibet Plateau, Western China. J Mt Sci 10(4):632–642. Scholar
  21. Kafumbata D, Jamu D, Chiotha S (2014) Riparian ecosystem resilience and livelihood strategies under test: lessons from Lake Chilwa in Malawi and other lakes in Africa. Phil Trans R Soc B 369:20130052. Scholar
  22. Lejon AGC, Renöfält BM, Nilsson C (2009) Conflicts associated with dam removal in Sweden. Ecol Soc 14:4CrossRefGoogle Scholar
  23. Letsebe PH (2012) A study of the impact of Lesotho Highlands Water Project on residents of Khohlo-Ntso: is it too late for equitable benefit sharing? Unpublished Thesis, Faculty of Arts, University of WitsGoogle Scholar
  24. Letšela T, Witkowski ETF, Balkwill K (2003) Plant resources used for subsistence in Tsehlanyane and Bokong in Lesotho. Econ Bot 57(4):619–639CrossRefGoogle Scholar
  25. Lewis F, Browne M, Oosthuizen S, Peerbay K (2015). Mapping climate change vulnerability and potential economic impacts in Lesotho. A case study of the Katse Dam catchment. Institute of Natural Resources NPC, PietermaritzburgGoogle Scholar
  26. LHDA (2002a) Analysis of the minimum degradation, treaty, design limitation and fourth scenarios for phase 1 development. Summary Report compiled by Metsi Consultants. Report No. LHDA 678-F-002. LHDA, Maseru, LesothoGoogle Scholar
  27. LHDA (2002b) Analysis of the minimum degradation, treaty, design limitation and fourth scenarios for phase 1 development, section 3: social consequences. Report compiled by H. Sabet and P. Martel. Report No. LHDA 678-F-002. LHDA, Maseru, LesothoGoogle Scholar
  28. LHDA (2003) Lesotho Highlands Water Project: phase 1: policy for instream flow requirements (2nd Edition Incorporating Corrigenda). July 30. MaseruGoogle Scholar
  29. LHDA (2006) Annual flow releases for in-stream flow requirement (IFR) implementation. Report N0.5. LHDA, Maseru, LesothoGoogle Scholar
  30. LHDA (2007) Annual flow releases for in-stream flow requirement (IFR) implementation. Report N0.7. LHDA, Maseru, LesothoGoogle Scholar
  31. LHDA (2016) IFR monitoring report for 2015 to 2016. LHDA, Maseru, LesothoGoogle Scholar
  32. Lin Q (2011) Influence of dams on river ecosystem and its countermeasures. J Water Resour Prot 3:60–66CrossRefGoogle Scholar
  33. Lu YR, Wang Y, Zhang H, Su P, Wang A, Jenkins RC, Ferrier M, Bailey SG (2015) Ecosystem health towards sustainability. Ecosyst Health Sustain 1(1):2. Scholar
  34. Manwa H (2014) Impacts of Lesotho Highlands Water Project on sustainable livelihoods. Mediterr J Soc Sci 5(15).
  35. Marcinkowski P, Grygoruk M (2017) Long-term downstream effects of a dam on a lowland river flow regime: case study of the Upper Narew. Water 9:783CrossRefGoogle Scholar
  36. Mashinini V (2010) The Lesotho Highlands Water Project and sustainable livelihoods: policy implications for SADC. (AISA Policy Brief no. 22).Google Scholar
  37. Mathebula B (2015) Assessment of the surface water quality of the main rivers feeding the Katse Dam, Lesotho. MSc Thesis. University of Pretoria, PretoriaGoogle Scholar
  38. Medley KE (1992) patterns of forest diversity along the Tana River, Kenya. J Trop Ecol 8:353–371CrossRefGoogle Scholar
  39. Metsi Consultants (2002) Summary of main findings for Phase 1 development. Report 678-F-001 Metsi Consultants 2002. Additional scenarios and production of a new final report (vol II). Report 678-F-002Google Scholar
  40. Moleko L, Thokoa M, Dlamini Z (2011) Challenges of managing communal compensation downstream of the LHWP dams as part of the Instream Flow Requirements (IFR) Policy and Procedures. WIT Trans Ecol Environ 153:387–395CrossRefGoogle Scholar
  41. Moqekela MC (2016) A valuation based approach for sustainable utilization of Khubelu Wetlands in Lesotho. Master of (Integrated Water Resources Management) Dissertation University of Dar es SalaamGoogle Scholar
  42. Mul M, Pettinotti L Amonoo NA, Bekoe-Obeng E, Obuobie E (2017) Dependence of riparian communities on ecosystem services in northern Ghana. Colombo, Sri Lanka: International Water Management Institute (IWMI). 43p. (IWMI Working Paper 179). doi:
  43. O’connor TG (2001) Effect of small catchment dams on downstream vegetation of a seasonal river in semi-arid African savanna. J Appl Ecol 38:1314–1325CrossRefGoogle Scholar
  44. Olaleye AO (2012) Mountain watershed in Lesotho: water quality, anthropogenic impacts and challenges. In: Křeček J, Haigh MJ, Hoffer T, Kubin E (eds) Management of mountain watersheds. Springer, Netherlands, pp 139–152Google Scholar
  45. Overton IC, Smith DM, Dalton J, Barchiesi S, Acreman MC, Stromberg JC, Kirby JM (2014) Implementing environmental flows in integrated water resources management and the ecosystem approach. Hydrol Sci J 59(3–4):860–877. Scholar
  46. Palmer A (2014) Towards assessing rangeland condition and production for The Kingdom of Lesotho. In: Chakela QK (ed) Sustainable land management in Sub-Saharan Africa: increasing land productivity. Book of Proceedings. Janeza Trdine 9, 51000 Rijeka, CroatiaGoogle Scholar
  47. Poff B, Koestner KA, Neary DG, Merritt D (2012) Threats to western United States riparian ecosystems: a bibliography. Gen. Tech. Rep. RMRS-GTR-269. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station: 78Google Scholar
  48. Ramaili LG (2006) Impact of the Lesotho Highlands Water Project in poverty alleviation in Lesotho. MA Thesis. University of Stellenbosch, South AfricaGoogle Scholar
  49. Rampai RI (2017) Effects of different grazing systems on ecosystem functions in Lesotho and Iceland. United Nations University Land Restoration Training Programme [final project].
  50. Reinecke MK (2013) Links between lateral riparian vegetation zones and flow. PhD Thesis, Faculty of Agri Sciences, Stellenbosch University, South AfricaGoogle Scholar
  51. Renofalt BM, Jansson R, Nilsson C (2010) Effects of hydropower generation and opportunities for environmental flow management in Swedish riverine ecosystems. Freshw Biol 55:49–67CrossRefGoogle Scholar
  52. Richter BD, Postel S, Revengan C, Scudder T, Lehner B, Churchill A, Chow M (2010) Lost in development’s shadow: the downstream human consequences of dams. Water Alternatives 3(2):14–42Google Scholar
  53. Schachtschneider K (2010) Water sourcing by riparian trees along ephemeral riverbeds. PhD Thesis, Department of Botany, University of Cape TownGoogle Scholar
  54. Schneider C, Flörke M, De Stefano L, Petersen-Perlman JD (2017) Hydrological threats to riparian wetlands of international importance – a global quantitative and qualitative analysis. Hydrol Earth Syst Sci 21:2799–2815CrossRefGoogle Scholar
  55. Sene KJ, Jones DA, Meigh JR, Farquharson FAK (1998) Rainfall and flow variations in the Lesotho Highlands. Int J Climatol 18:329–345CrossRefGoogle Scholar
  56. Swanson S, Wyman S, Evans C (2015) Practical grazing management to maintain or restore riparian functions and values on rangelands. J Rangeland Appl 2:1–28Google Scholar
  57. Talukdar S, Pal S (2018) Application of frequency ratio and logistic regression models for assessing physical wetland vulnerability in Punarbhaba river basin of Indo-Bangladesh. Hum Ecol Risk Assess 24(5):1291–1311. Scholar
  58. Timpe K, Kaplan D (2017) The changing hydrology of a dammed Amazon. Sci Adv 3:1–13CrossRefGoogle Scholar
  59. Van Zinderen Bakker EM, Werger MJA (1974) Environment, vegetation and phytogeography of the high altitude bogs of Lesotho. Vegetation 29:37–49CrossRefGoogle Scholar
  60. Varty N (1990) Ecology of the small mammals in the riverine forests of the Jubba Valley, southern Somalia. J Trop Ecol 6:179–189CrossRefGoogle Scholar
  61. Wang Y, Rhoads BL, Wang D (2016) Assessment of the flow regime alterations in the middle reach of the Yangtze River associated with dam construction: potential ecological implications. Hydrol Process 30:3949–3966CrossRefGoogle Scholar
  62. Webb AD (2017) Fire effects and management in riparian ecosystems of the Southwestern United States and Mexico. MSc Thesis, University of Arizona.

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Patrick Gwimbi
    • 1
  • Thabo E. Rakuoane
    • 1
  1. 1.Department of Environmental HealthNational University of LesothoRomaLesotho

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