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YOUR INVOLVEMENT Your involvement is very important to us. While at this stage we seek to inform, not to solicit comment, we urge you to submit comments on the Draft IFR Policy when it is released. Details about the venues where documentation is available, and where the Draft IFR Policy will be posted are provided on the next page. WHO TO CONTACT ABOUT THIS PROJECT Should you wish to submit comments, please do so to the following email address lhwp@lhda.org.ls Or by fax to +266 325775, for the attention of Mr R Maphetla Chief Executive Officer LHDA PO Box 7332 Maseru 100 Lesotho Should you wish to discuss anything relating to the IFR policy process, or to obtain further information, do not hesitate to contact the following persons at LHDA: Ms. M. Mothepu Deputy General Manager ESSG Phone: +266 835 0825 +266 85 0679 (Cell phone) Mr. Taole Tesele IFR Co-ordinator Phone: +266 835 0731 +266 85 2143 (Cell phone) Description of the Lesotho Highlands Lesotho is a land-locked country 30 355km 2 in extent. The eastern two-thirds, called the Highlands, are formed by the rugged Drakensberg and Maloti ranges, which form a high, dissected plateau with an average elevation of about 2 500 metres above sea level (masl). The narrow river valleys are steep-sided; the landscape is one of deeply incised valleys and peaks. The Senqu (Orange) River drains the eastern and southern sectors and has several large tributaries, including the Malibamats’o, Senqunyane and Matsoku rivers, which are the locations for LHWP structures (see map). Highland catchments are characterised by high rainfall, temperate summers and long, cold winters, and they have high water yields due to rapid runoff from the steep slopes. Rainfall occurs predominantly as thunderstorms of high intensity and short duration. The nature of the rainfall and the rapid movement of water off the steep slopes and thin soil results in a quick drainage reaction time. Highly variable, but distinct wet, dry and transitional seasons are identifiable from hydrological records. The wet/rainy season extends from December to March, while the dry season usually extends from June through September. Grasslands and shrublands dominate highland vegetation; wetlands occur in all drainage lines. Vegetation zones along rivers typically have a higher biodiversity than elsewhere and a higher proportion of woody vegetation, both indigenous and exotic species. The wild animal communities of Lesotho are distinctive, with several endemic species, but wildlife densities are very low due to heavy, uncontrolled exploitation. The human population along the rivers downstream of the LHWP structures within Lesotho live in small villages, with a small proportion living in larger settlements such as Marakabei. It has been estimated that some 8 300 households in a 5km corridor on each side of the downstream rivers may be significantly affected by Phase 1 of the LHWP. While foreign employment in South Africa represents an important, although declining, source of income, rural people are heavily dependent on local resources for their livelihood. Agriculture is an important source of livelihood, but agricultural plots are constrained in size by topography and soil depths. Relatively more and better land is available along the Matsoku and upper Senqunyane Rivers than along the deeply incised Malibamats’o and upper Senqu rivers. The nutrition status of local people, especially children, is low, even by Lesotho rural standards, and there is a high incidence of childhood infectious diseases as well as water-related diseases. Livestock are abundant in the area (estimated populations of 68 000 catttle, 78 000 sheep, 131 000 goats and 24 000 horses and donkeys). IFR Study Scenarios Minimum Degradation Scenario This scenario was developed as a hypothetical condition, in which maintenance of the rivers in a state of minimal degradation from their current condition was the main objective and only thereafter would water delivery needs be catered for (ie transferred to SA). It assumed that 60-65% of Mean Annual Runoff would be released to downstream ecosystems. This scenario allowed specialists to consider interactively baseline conditions relative to flow levels and to establish the flows below which significant ecological and physical changes could be anticipated. It should be noted that this scenario is not technically achievable due to design constraints on the structures 6
WHERE TO GET MORE INFORMATION The 3 key reports: ❏ Metsi Consultants (2002) Report 678-F-001, Summary of Main Findings for Phase 1 Development ❏ Metsi Consultants (2002) Report 678-F-002, Additional Scenarios and Production of a New Final Report (Vol. II) ❏ S. Klasen (2002) The Costs and Benefits of Changing Instream Flow Requirements are available on the following websites: ❏ www.lhwp.org.ls. ❏ www.lesotho.gov.ls ❏ www.dwaf.gov.za ❏ www.sametsi.com Hard copies of these reports are lodged for public inspection at the following venues: ❏ LHDA Library, 3rd Floor, Post Office Building, Kingsway, Maseru, Lesotho ❏ National Environmental Secretariat Library, Post Office Building, Maseru ❏ National University of Lesotho Library, Roma, Lesotho ❏ DWAF Library, 3rd Floor Sedibeng Bldg, Schoeman St, Pretoria ❏ World Bank office, Pro-Equity Court, 1250 Pretorius Street, Pretoria ❏ University of Cape Town Library, Rondebosch, Cape Town ❏ Public Information Center, World Bank, 1818 H Street NW, Washington, DC Should you wish to read further, a full set of Metsi Consultants Contract 648 reports are lodged at: ❏ LHDA Library, 3rd Floor, Post Office Building, Kingsway, Maseru, Lesotho ❏ DWAF Library, 3rd Floor, Sedibeng Bldg, Schoeman St, Pretoria, South Africa ❏ National University of Lesotho Library, Roma, Lesotho Treaty Minimum Release Scenario This is the scenario generated by application of the minimum release conditions specified in the Treaty and is at the opposite end of the range from Minimum Degradation in terms of water requirements. Conceptually, the scenario differs from that above in that the volumes of delivery water are first specified and consequential river conditions then assessed. Design Limitation Scenario This is a scenario based on the practical limitations of flow releases imposed by the designs of the Phase 1 structures. In terms of volumes of water releases, it is between the above two scenarios. Fourth (Intermediate) Scenario This scenario was selected to fall between the Treaty Minimum and Design Limitation scenarios and to provide a reference point between the former (legally defined and highest water delivery, but most severe environmental and socioeconomic impacts) and the latter (possible within engineering constraints, but likely to have high impacts on water and revenues). Summary of Findings Hydrological changes The Table below gives a global picture of the hydrological changes that are predicted to occur under each of the four scenarios. It is from the changes in the river hydrology or flow regime that all other predicted changes are derived. This overview presents the overall amount of water available to downstream ecosystems on an annual basis, as a proportion of mean annual runoff (MAR), this being an estimate of the average amount of water draining from the catchment in a year. Table 1: Historical MAR, the annual volume allocated to the river and the percentage of historical MAR that this represents, under each of the four scenarios at each IFR site for LHWP Phase 1 development. Shaded sites represent reaches immediately downstream of the dams in Phase 1a and 1b IFR Site Historical MAR Minimum Degradation Scenario MCM a -l MCM a -l %MAR MCM a -l %MAR MCM a -l %MAR MCM a -l %MAR 1 87 51 59 35 40 35 40 31 36 2 554 366 66 22 4 184 33 97 18 3 774 436 56 128 17 315 41 227 29 4 1572 866 55 831 53 831 53 831 53 5 1924 1194 62 6 3330 2171 65 Treaty Minimum Scenario Design Limitation Scenario Fourth Scenario Flows sufficient for Minimum Degradation 7 355 231 65 48 13 126 35 77 22 8 592 397 67 158 27 254 43 195 33 Site 1 = Matsoku R, immediately downstream of Matsoku Weir (30km) Site 2 = Malibamats’o R, immediately downstream of Katse Dam (20km) Site 7 = Senqunyane R immediately downstream of Mohale Dam (90km) Site 3 = Malibamats’o R at Paray, downstream of confluence with Matsoku R (35km) Site 4 = Senqu R at Sehonghong, representing Senqu between confluences of Malibamats’o and Tsoelike rivers (125km) Site 5 = Senqu R at Whitehills, between confluences of Tsoelike and Senqunyane rivers (85km) Site 6 = Senqu R at Seaka Bridge, from confluence with Senqunyane to South African border (140km) Site 8 = Senqunyane R upstream of the confluence with the Senqu R, from confluence with Lesobeng R to the confluence with the Senqu R (40km). 7
Page 1 and 2: This document is intended as a mean
Page 3 and 4: PUBLIC DISCLOSURE AND INVOLVEMENT P
Page 5: Instream Flow Requirements: Theory
Page 9 and 10: RECORDED IMPACTS Metsi Consultants

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