3 rd International Seminar on Watershed Management, Wisconsin, USA June 22 – July 07, 2004

Water Resources Development and Management in Botswana

Presented by Balisi Bernard Khupe

1 TOPICS

• Introduction • Geophysical Feature • Population & Economy • Water Resources • Water Demands • Long-term Water Resources Development • Ground Water Monitoring

Angola Zambia N Chobe River Zambezi River Kasane

Zimbabwe Okavango Delta Maun

Namibia Makgadikgadi Lake Pans Ngami Francistown Orapa Shashe River Ghanzi Selibe Phikwe REPUBLIC Serowe OF Palapye BOTSWANA Mahalapye Limpopo River

Molepolole

Jwaneng Mochudi GABORONE Kanye Lobatse

Molopo River Tsabong Republic of South Africa

2 Figure 2. Average annual runoff from selected countries 1500

Ecuador 1,166 mm

1000

Italy 528 mm Thailand Sweden 428 mm 500 390 mm Estimated runoff mm/a runoff Estimated

Zimbabwe Botswana 52 mm 1.2 mm

0 Area of Country

Table 2. Comparison of surface resources of Botswana and other countries [1,2,3].

Estimated Annual Runoff Country Area km2 Population*x1000 106 m3 mm m3/capita

Botswana 582,000 1,681 705 ** 1.2 419 Australia 7,682,000 19,138 412,500 54 21,550

Ecuador 243,500 12,646 283,980 1,166 22,460 India 3,169,000 1,008,937 1,678,000 530 1,660

Israel 21,000 6,040 740 35 123 Italy 301,000 57,530 159,000 528 2,760 Japan 373,000 127,096 540,000 1,450 4,250 South Africa 1,141,000 43,309 53,500 47 1,240

Sweden 450,300 8,842 175,600 390 19,860 Thailand 514,000 62,806 220,000 428 3,500 Zimbabwe 384,000 12,627 19,900 *** 52 1,580 * 2003 figures from UN World ** excluding Okavango River and Chobe *** excluding the Zambezi Water Report and 2001 River system River census for Botswana

3 Table 3. Estimated runoff of international border rivers [1]

Estimated Annual Mean Runoff River Area 106 m3 mm km2 Zambezi at Victoria Falls 360,700 40,100 113

Okavango at border inflow 200,000 9,910 50 (Mohembo) Chobe river system 131,000 1,310 10

Limpopo (Point Drift) 158,000 620 4

Table 4. Main aquifer formation in Botswana

Age Litho-stratigraphic Lithology Aquifer area Regional Borehole unit km2 Transmiss Suc Type ivity m2/d ces s rat e % Cenozoic Sand Rivers of E. Botswana Gravel, sand P 400-1500 100 and the Okavango delta 350 72-100 Alluvium (Limpopo) Gravel, sand 40 P 0.7-35 Kalahari Beds Sand, sandstone, cal-crete, 201000 P silcre-te, clay Mesozoic Karoo Supergroup 6000 F 1.5-2.5 68-94 Stormberg Basalt 138000 F-P 1-40 92-100 Lebung Sandstone 94000 F-P 0.9-70 86-100 Ecca, Beaufort Arkose, sandstone, siltstone, mudstone, coal Protero-zo E and S Botswana 49000 F 1-8 68-100 ic Waterberg Supergroup Conglomerate, siltstone, 4000 F-K quartzite, shale 400 F 2-5 71-87 Transvaal Supergroup Dolomite 33000 F 62 W, NW and N Botswana 1000 F-K 0.2 79-100 Olifantshoek Sequence Quartzite, schist, 0.6-2 por-phyry Damara Sequence Arkose, quartzite, schist, mudstone, shale Dolomite Archean Ventersdorp Supergroup Porphyry, felsite, 50 F 0.7 6 greywacke 61000 F 0.5-2 44-96 Archean base-ment of Granite, gneiss, SE and E Botswana migmatite, amphibolite F=fractured K=karstified P=porous Successful borehole rate > 0.01 m3/h

4 Figure 4. Wellfields in Botswana

Angola Zambia N

Zimbabwe

Maun Namibia

Francistown Orapa Ghanzi Paje Talana Farms REPUBLIC Serowe Seleka Farms OF Palapye Lerala Shoshong Lecheng BOTSWANA Bonwapitse Palla Rd Sefhare Jwaneng Botlhapatlou Malotwane Gaotlhobogwe Molepolole E. Moshupa & Thamaga Metsemothlaba

Kanye Ramotswa Sedibeng Pitsanyane

Tsabong Republic of South Africa

Table 6. Major difference between WHO and Botswana drinking water quality guidelines

SUBSTANCE Units WHO BOTSWANA Desired Permissible Maximum Permissible Total Dissolved mg/l 1000 1000 1500 2000* Solids (TDS) Sulphate mg/l 400 400 --- 600* Chloride mg/l 250 250 600 800 Nitrate mg/l 45 45 100 100 Fluoride mg/l 1.5 1.5 3.0 3.0 Iron mg/l 0.3 0.3 1.0 3.0* Manganese mg/l 0.1 0.1 0.5 0.5* * Tentative figure

5 NATIONAL WATER MASTER PLAN SCOPE • review of socio-economic background (as influencing the demands for water) • estimation of water demands for all sectors of the nation • assessment of the quality and quantity of Botswana’s water resources • rural water supply studies • sanitation aspects (water needs, return flows) • formulation of alternative water development strategies for rural and urban areas • economic and financial studies • examination of institutional, legal and environmental implications • recommendation of preferred course of action

NATIONAL WATER MASTER PLAN OBJECTIVES • the identification of existing and potential surface and groundwater resources

• the projection of future demands from 1990 to 2020

• the timing of future water resource developments to meet the rising rural, urban and industrial needs of the nation

• the selection of water pricing policies to ensure both optimal use of this key resource and balanced socially equitable development, and

• an assessment of the environmental and social impacts of changing patterns of water use

6 MAJOR WATER ISSUES IN THE 21ST CENTURY • Water Conservation and Efficient use of water

• Water pricing and cost recovery

• Social and environmental considerations

• Institutional response to better management

• Management of international Water Bodies

• Proper analytical frameworks

NATIONAL WATER MASTER PLAN SOURCES OF WATER

• Groundwater boreholes traditional wells sand rivers

• Surface water perennial rivers seasonal rivers and pans dams

• Other water recycling water conservation roof drainage desalination

7 Table 1. A summary of water demands in Botswana (106m3/a) divided into various categories of consumers [2] Category Estimated Demand Demand consumpti 2000 2020 on 1990 Settlements (Domestic) 36 78 175

Mining and Energy 23 36 64 Livestock 35 45 44 Irrigation/Forestry 19 29 47 Wildlife 6 6 6 Total 119.0 194 336

Table 5. Water demands to south-eastern Botswana and the greater Gaborone Region, water supply from local sources and required additional supply. Figures given in million m3/a

Year Total Local Deficit to be % deficit of Demand sources supplied from total supply NSC or other demand sources 1998 31.5 22.6 8.9 28 1999 33.6 22.6 11.0 33 2000 35.7 22.6 13.1 37 2010 56.1 22.6 33.5 60 2020 81.7 22.6 54.1 72

8 Figure 3. The North-South Carrier Water Project in Botswana

Makgadikgadi Pans

Orapa Francistown Shashe Dam Shashe River

Letsibogo Dam Selibe Phikwe

Serowe

Limpopo River Republic of Palapye Botswana Mahalapye Palla Rd Chepete

Jwaneng Masama Wellfield Goatlhobogwe Makhujwane Republic of Booka Dam South Africa Mochudi Molepolole Waterberg Jwaneng E. Suping Thamaga GABORONE Molatedi Moshupa Gaborone Dam Dam Kanye Ramotswa Kgakgwe Nnywane Dam

Ramonnedi Lobatse Legend

Wellfield

Village

Figure 6. Combined wellfield protection zoneation and aquifer vulnerability map [12]

9 Figure 5. Monitoring of groundwater level in production well 4700 at Dukwi wellfield. The borehole is pumped at an average 11 hours/day at a rate of 35 m3/h. The whole wellfield produces 2,250 m3/day -35 Water level before start of pumping -40 -45 -50 -55 Water level at end of pumping -60 Pump intake level -65 W ater level (m .b.g.s.) -70

Dec-92 Dec-93 Dec-94 Dec-95 Dec-96 Dec-97 Date

10 11 12