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World Bank Document Document of The World Bank FOR OFFICIAL USE ONLY Public Disclosure Authorized Report No. 4378-BT STAFF APPRAISAL REPORT Public Disclosure Authorized BOTSWANA THIRD WATER SUPPLY PROJECT Public Disclosure Authorized May 9, 1983 Water Supply and Urban Development Division Public Disclosure Authorized Eastern Africa Projects Department This document has a restricted distribution and may be used by recipients only in the performance of their official duties. Its contents may not otherwise be disclosed without World Bank authorization. | BOTSWANA APPRAISAL OF THIRD WATER SUPPLY PROJECT Currency Equivalents Currency Unit = Pula (P) 1 Pula = 100 Thebe = US$0.9 US$1 = P 1.1 Weights and Measures I Imperial Gallon (Ig) = 1.2 US Gallons = 4.55 liters (1) I cubic meter (m 3 ) = 220 Ig, 264.2 US gallons, or 1 kiloliter (kl) 1 liter per capita per day = I lcd 1 million Imperial gallon per day (Imgd) = 4,546 m3 /day 1 meter (m) = 3.28 feet (39.37 inches) 1 millimeter (mm) = 0.039 inches 1 kilometer (km) = 0.62 miles 2 1 square kilometer (km ) = 0.386 square miles = 247 acres (ac) Abbreviations and Acronyms AfDF = African Development Fund BPC = Botswana Power Corporation CIDA = Canadian International Development Agency CDC = Commonwealth Development Corporation DCs = District Councils DWA = Department of Water Affairs (MRWA) GTC = Gaborone Town Council Gibb = Sir Alexander Gibb & Partners Government (GOB) = Government of the Republic of Botswana GSD = Geological SturveyDepartment (MRWA) GWEU = Gaborone Water & Electricity Unit IDRC = International Development Research Center of Canada MFDP = Ministry of Finance & Development Planning MLGL = Ministry of Local Government & Lands MOH = Ministry of Health ~TRWA = Ministry of Mineral Resources & Water Affairs MWC = Ministry of Works & Communications NDP = National Development Plan, 1979-1985 RSA = Republic of SouithAfrica SIDA = Swedish International Development Authority UK = United Kingdom of Great Britain & Northern Ireland UNDP = United Nations Development Programme USAID = United States Agency for International Development WUC = Water Utilities Corporation Fiscal Year (FY) April 1 to March 31 LIST OF ANNEXES ANNEX DESCRIPTION 1 Sector Investment Programme 2 Population/Water Demand Growth 1979-1990 3 Description of the Proposed Water Supply Facilities 4 Description of the Gabarone Dam Raising Works 5 Project Cost Estimates 6 Project Implementation Schedule 7 Disbursement Schedule 8 Yields of Proposed Raw Water Sources and Average Water Demand for Gabarone 9 Water Utilities Corporation - Organization Chart 10 WUC / Gabarone/Lobatse Income Statement 11 WUC - Gabarone/Lobatse Division Financing Plan 12 Economic Rate of Return for Gabarone WS/Average Investment Cost of Water 13 Proposed Monitoring Guidelines MAPS IBRD 16921R - Layout of Proposed Gabarone Dam IBRD 16922 - Catchment Area of Gabarone Dam IBRD 16923R - Existing and Proposed Water Supply System of Gabarone I BOTSWANA THIRD WATER SUPPLY PROJECT I. THE WATER SUPPLY AND WASTE DISPOSAL SECTOR Country Background 1.01 Botswana, which has an area of about 582,000 km2 (225,000 sq. mi.), is landlocked and is bordered by Zimbabwe, the Republic of South Africa (RSA), Namibia, and Zambia. Botswana occupies the central portion of the great plateau of southern Africa and the ground surface, which is relatively flat, averages about 1,000 meters (3,000 ft.) in elevation. 1.02 The climate is continental and semi-arid with an average annual rainfall of 475 mm which is highly erratic and unevenly distributed. 1/ Precipitation is seasonal, mostly occuring during the period of November through April. Temperatures generally range between 5CC and 38°C with wide diurnal variation particularly evident during the "southern" winter months (May through October). 1.03 The population of Botswana, mainly situated in eastern Botswana, was 935,000 according to a 1981 census and is increasing at about 3.5% annually. Although the urban population comprises only about 16% (resident in five towns, Gaborone, Lobatse, Francistown, Selebi-Phikwe and Orapa), the country has one of the world's highest urbanization rates, currently close to 12% per year. 1.04 The rangeland of Botswana basically consists of a number of bush and tree savannah types. In only about 5% of the surface area of Botswana do adequate rainfall and suitable soils occur together to provide potential for arable agriculture. 1.05 Intensive, large-scale prospecting for minerals has begun only in recent years. Commercially exploitable deposits of diamonds, copper-nickel and coal have been brought into production at Orapa, Selebi-Phikwe and Morupule, respectively. A third diamond mine has just been put in operation at Jwaneng. Water Resources 1.06 Although Botswana's total water resources are fairly substantial 2/, due to their unfavorable location and/or variability in occurence, the country is effectively water deficient. Surface water, representing over 85% of the total resources and of good quality, occurs mainly in the Okavango River located in the north and, to a lesser extent, in border rivers. Except for the Limpopo and its tributaries located in eastern / Average annual rainfall ranges from 250 mm in the southwest to more than 650 mm in the northeast. 2/ The total annual resource, though not well documented, has been estimated at about 21 billion m3 of which approximately 18 billion m is surface water and about 3 billion m3 is ground water. - 2 - Botswana, they are little utilized. Surface water located elsewhere, although more accessible, is ephemeral and small in volume (representing less than 5% of all surface water). 1.07 Although ground water is believed to underlie much of Botswana, these resources have not been fully investigated. The majority of existing boreholes are located in the eastern part of the country where 90% of the population is located. The country has over 5,000 registered boreholes, and the number of unregistered boreholes is estimated at 50% of this figure. Shallow wells are much smaller in number. Yields of individual boreholes are small 3/ and natural water quality in some areas is unacceptable for human consumption due to high salinity. Many of the wells are unuseable during extended drought periods due to lowered water levels and the small storage capacity of individual aquifers. Further, due to the nature of the aquifers and to inadequate control of the disposal of waste from livestock and/or humans, high nitrate concentrations and serious fecal bacterial contamination exists in ground water underlying many villages and certain of the towns. 1.08 In recognition of increasing water demands in the eastern portion of the country, the Government of Botswana (GOB) recently investigated the feasibility of developing supplies from several potentially attractive sources. The first of these studies, which was financed by the United Nations Development Programme (UNDP), concerned transfer of water from the Okavango Delta to potential areas of demand. The studies concluded that such a transfer is unlikely to be economic in the foreseeable future. The practical limitations are that the demand must be either close at hand or very large and concentrated. A second study, financed by the African Development Fund (AfDF), concerned the feasibility of water development in northeast Botswana. Several attractive schemes were identified in this study including that of the just completed Second Water Supply (Francistown) Project financed by the World Bank. A third study by the Department of Water Affairs (DWA) of the Ministry of Mineral Resources and Water Affairs (MRWA) investigated the feasibility of developing supplies from principal sand rivers of eastern Botswana. Findings of this study indicate that sand rivers have potential mainly as supplies to villages and other minor demand centers. 1.09 Water resources studies relevant to the proposed Third Water Supply Project (Gaborone) have been: (i) "Water Resources Reconnaissance of lower Metsemotlhaba and lower Ngotwane River" prepared by B.G.A. Lund and Partners, RSA, 1977. (ii) "A Reconnaissance Study for Major Surface Water Schemes in Eastern Botswana", prepared by Sir Alexander Gibb and Partners, 1977. (iii) "Gaborone Water Resources, Review of Alternative Development Options" prepared by Sir Alexander Gibb and Partners, 1981. 3/ Only 17% of all wells are yielding more than 2.5 litres per second, and typical depths range from 30 to 100 m. - 3 -. A complete list of all documents relevant to the project is available on the project file. Sector Legislation 1.10 Various Parliamentary Acts dealing purely with water sector issues, legislated between 1956 and 1970, together with the Tribal Land Act of 1968 and the Town and Country Planning Act of 1977, provide adequate legislative instruments. However to further improve the situation Government have invited SIDA to study all existing water legislation and obligations covering domestic and international water regulation. The studies are in progress and will also include recommendations for necessary amendment of legislation to deal with the evolving water needs and establish controls for the management of Botswana's own national water resources and common international water resources. During negotiation, Government agreed to make the studies available for Bank review and comment prior to introducing legislative changes. (Guarantee Agreement Section 3.02). Sector Organization 1.11 Four different ministries are active in the sector. Two of these, the Ministry of Mineral Resources and Water Affairs
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