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Preface Annex 1
OVERVIEW OF RESOURCES
Southern Africa is vulnerable to environmental change due to its limited water resources. Poverty is widespread, with large numbers of its people living on less than a dollar a day, HIV/AIDs is a growing problem in many of the countries and its population is largely rural and heavily dependent on agriculture. Chapter 1: The Human Dimension gives an overview of these issues and their significance for environmental management and economic opportunity.
This sub-region has 12 major internationally shared river basins, of which the four largest basins are the Zambezi, Orange, Okavango and Limpopo river basins. Surface run-off in the northern and eastern parts is available in sufficient quantities throughout the year. In the south-western part it only occurs with extreme episodic rainfall events. Under such conditions, people rely largely on dams and groundwater resources. Major groundwater resources are found in the Kalahari- Etosha, Karoo, Cape Fold Belt, East Kalahari Precambrian Belt and the coastal basins of Mozambique and Tanzania. The region has experienced floods in the northeast and episodes of severe and prolonged droughts in other places.
ENDOWMENT AND OPPORTUNITIES
Southern Africa’s freshwater resources are critical aspects of local livelihoods and a central component of many economic activities. Several are also recognized as globally significant from a biological diversity perspective. These include the Okavango Delta, the St. Lucia Wetlands and Lake Malawi.
Lake Malawi is the third largest lake in Africa. It is 560 km long, 75 km wide (at maximum width), has a maximum depth of 700 m at its western shore and a mean depth of about 290 m, with lake capacity (volume) estimated at 8 400 km³ (ECA 2000). It is an important resource for people in Tanzania, Malawi and Mozambique, who rely on it for potable water, food, irrigation and hydropower (S & E 1999). It is also important for navigation, transportation and tourism, and supports both subsistence and commercial fisheries (ECA 2000). It has the largest number of fish species of any lake in the world, estimated at more than 600, of which half have been identified. Many of these are endemic (S & E 1999).
To meet the demand of the growing population, solutions in the past mainly focused on the supply side of resource management. As a result, as shown in Figure 7, Southern Africa has a high concentration of dams and inter-basin transfer schemes. Yet, cheaper and readily accessible solutions have proven to be possible and significant strides have been made towards the development of infrastructure for water supply and sanitation services. Among the adopted measures are improved maintenance and efficiency of urban water distribution networks, and improvement of sewage treatment and disposal facilities. Various tools are deployed to control the impacts of discharges on water quality, such as subsidies per unit of pollution emission abatement, waste charges, and penalties for pollution, following “the polluter-pays” principle.
Irrigated agriculture places the highest demand on water and many countries are introducing more efficient, cost-effective and sustainable water demand management (WDM) measures aimed at controlling demand to conserve water. Namibia, for instance, has been successful in implementing a wide range of WDM measures including plastic covers over the soil to reduce evaporation, block-tariff systems in the urban sector to curb excessive water use, leak detection programmes and public campaigns to educate people about the role of water (Chiuta and others 2002).
CHALLENGES FACED IN REALIZING DEVELOPMENT OPPORTUNITIES
Future projections for Southern Africa for 2025 (Chiuta and others 2002) suggest that water availability per person will sharply decrease for most countries (see Figure 2). Southern Africa is among the few regions in the world for which most global climate models agree upon an increase in aridity in the future and hence a further lowering of water availability for livelihoods (DWC 2003, IPCC 2001). In particular, the projection looks bleak for Malawi and South Africa. In addition, Lesotho, Tanzania and Zimbabwe are expected to experience water stress by 2025, while Swaziland is likely to experience water quality and availability problems in the dry season.
The sub-region has experienced floods in the northeast and episodes of severe and prolonged droughts in other places. Repeated droughts affect freshwater availability and make the sub-region prone to soil erosion, which in turn affects water quality through siltation. The extreme amounts of soils transported to the coast especially impact the mangrove forests, causing asphyxiation of the buried roots.
Overabstraction of surface water resources has caused significant changes in the flow regimes and water quality of many rivers, leading to negative impacts on aquatic biota and subsequent loss of ecological function and health (Hirji and others 2002). For example, the building of the Kariba Dam altered the hydrological regime of the Zambezi River and changed the Marrameu floodplain to a dry, bushy area prone to fire. Additional threats to the remaining Zambezi basin wetlands include reduced flows caused by droughts and water abstractions, aquatic weed infestation, pesticides (especially DDT), infrastructure development like dams, overuse of resources due to human pressures, uncontrolled fires, pollution and deforestation (Schuijt 2002).
Pollution, especially from agricultural drainage and wash-off, urban wash-off and effluent return flows, industries, mining, and areas with insufficient sanitation services, is increasing. Pollution of groundwater resources is of particular concern because it is costly and time-consuming to rehabilitate. Water quality management should therefore form an integral part of a strategy for water resource management (DWAF 2004).
Invasive alien species, and in particular Eichhornia crassipes (water hyacinth), threatens many freshwater bodies (Chenje 2000).
STRATEGIES TO IMPROVE DEVELOPMENT OPPORTUNITIES
There has been good progress in water sector reforms since the late 1990s, with an increasingly integrated approach to water resource management (surface water, groundwater, socioeconomic and other issues dealt with in an integrated manner). The reforms, which include the setting up of new institutions with new functions, responsibilities, legislation and guidelines for water resource development and management, take place at different paces and at different scales. Box 13 lists some of the main lessons learnt from the reforms providing opportunities for further improvements in the area of good management.
Most countries have established catchment management institutions with specified powers and responsibilities. Transboundary cooperation on water matters takes place within the framework of the Protocol on Shared Watercourses (SADC 1995, SADC 2000). River Basin Commissions have been established in all of the four largest river basins, with the most recent developments being the establishment of the Zambezi Watercourse Commission in 2004 and the Limpopo Watercourse Commission in 2003.
Capacity enhancement programmes at various academic and institutional levels, such as WaterNet and the GWP, support and facilitate the adoption of IWRM approaches. Water-related data and information are increasingly compiled according to hydrologic boundaries. Opportunities for further work are in the areas of climate variability and change, water pollution, groundwater recharge and environmental flow.
Many Southern African countries have embarked on cost-recovery approaches or on enhancing private sector participation in providing water to urban and rural areas at various degrees of recovery rates. Box 14 describes an initiative that was undertaken to improve water and sanitation service provision to poor urban and rural communities.
Other measures that are possible for solving the problem of financing water projects in developing countries, besides donor support, include the encouragement of international commercial lending, the promotion of private investment and operations, and the recognition and support of community initiatives and non-governmental organizations by providing them with the resources necessary to perform their important role.