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Preface Annex 1
WESTERN INDIAN OCEAN ISLANDS
OVERVIEW OF RESOURCES
The Western Indian Ocean (WIO) islands are separated by large expanses of ocean and do not share any freshwater resources. Freshwater resources vary considerably across the islands.
Madagascar can be divided into two major basins – one draining to the west into the Mozambique Channel and the other draining to the east into the Indian Ocean. Water in Madagascar, Mauritius and the Seychelles is primarily extracted from rivers on the main inhabited islands through the construction of dams and reservoirs, while the islands of Comoros are heavily dependent on groundwater resources. The islands are subject to tropical storms or cyclones with heavy rainfall from November to May giving rise to periodic flooding. Despite the relative abundance of rainfall, the islands also experience periods of water shortage.
There are large variations in rainfall across the countries and this has implications for available freshwater resources. All the countries experience extended dry seasons with periods of heavy rain, torrential at times, which present technical problems for storage, treatment and distribution. Climatic patterns are discussed in Chapter 2: Atmosphere.
ENDOWMENT AND OPPORTUNITIES
Wetlands occur throughout the island states. These wetlands are important habitats that provide breeding grounds for large numbers of waterfowl. These natural assets make the island states ideal tourist destinations.
On the Mauritius island of Agalega, 1 000 km north of Mauritius main island (Government of Mauritius 2005), the use of groundwater is declining for domestic or agricultural purposes, because of saltwater intrusion and land pollution; rainwater harvesting from pitched roofs is proving a problem because of faecal contamination from birds.
In the areas of public awareness and information, and economic measures, such as metering and charging for water use, there are opportunities to further curtail the demand for freshwater.
CHALLENGES FACED IN REALIZING OPPORTUNITIES FOR DEVELOPMENT
Projections for the WIO islands place Mauritius in the category of water-stressed countries and Comoros in the category of water-scarce countries by 2025 (see Figure 2). Comoros is currently on the threshold, with just 1 700 m3 available per person per year (UNEP 2005a). Water availability is a problem across the sub- region (UNEP 2005a):
In the Comoros, seawater intrusion reaches as far as 2 km inland due to the high water table around the coast (UNEP 2004). There are also problems of contamination of groundwater through seepage from septic tanks, substandard equipment and an insufficient number of water pumps.
The Intergovernmental Panel on Climate Change’s (IPCC) projected worst-case scenario of a 1 m sea-level rise by 2100 would result in loss of coastal land, agricultural opportunities, groundwater resources (due to salinization), biodiversity critical to community support, and in loss of livelihoods (IPCC 2001). The social impacts of a sea-level rise will cause migration and displacement of people, water-related diseases and water supply problems.
In the Seychelles, high fertilizer use means that rivers have fertilizer loads of up to 25 kg per day (UNEP 2005b). Wells in Mauritius have high nitrate levels reaching 50 microgrammes per litre, which is up to the World Health Organization defined safety limits (UNEP 2005b). Mauritius uses, on average, 57 500 tonnes of fertilizer annually, representing 600 kg per hectare, or three times the rate in western Europe (UNEP 2005b).
For many people in many of the WIO islands, waterborne and tropical communicable diseases are widespread, as a result of contamination of water supplies by human waste. The Comoros, for example, suffered cholera epidemics in 1975, 1998 and 2001. Two recent outbreaks were associated with poor sanitation and pollution of freshwater. Poor disposal of waste, particularly containers, is also generating increased risk of malarial infections, especially in Madagascar and the Comoros. The containers, ranging from old plastic bags to paint tins, accumulate rainwater, which is an ideal breeding ground for disease-carrying insects. Both Mauritius and the Seychelles have developed organized waste management schemes. In the Comoros, collection and disposal of waste is poorly managed.
In the Comoros, malaria is one of the principal causes of morbidity and mortality, being associated with 25 per cent of hospital admissions and 10-25 per cent of deaths in children under five years old (WHO/UNICEF 2003). Diarrhoea is a significant cause of morbidity in children in the Comoros and is associated with poor water quality.
Madagascar has health problems associated with stagnant water in irrigation canals in rice fields which promote mosquito breeding and are host to the spread of the parasites producing bilharzia. Mauritius and the Seychelles are relatively free from diseases affected by poor quality of water. Malaria has been successfully eradicated in Mauritius, although in the past it was responsible for over 2 000 deaths per year. Tourist areas throughout the sub-region have yet to introduce quality controls on water in bathing areas, although the adoption of the Blue Flag schemes of western Europe is being considered.
STRATEGIES FOR IMPROVING DEVELOPMENT OPPORTUNITIES
The role of the private sector in financing water projects and infrastructure is increasing, although more so in Mauritius and the Seychelles than in Madagascar and Comoros (UNEP 2004). In the Seychelles, the role and importance of NGOs in sustainable development has increased since 1996.
In January 2005, the Mauritius Strategy was adopted, by the Small Island Developing States (SIDS) and the international community, to ensure the successful implementation of the 1994 Barbados Programme of Action (BPoA). The BPoA focuses on problems SIDS face related to climate change and sea-level rise, natural and environmental disasters, freshwater resources, and capacity- building. Selected challenges and actions related to freshwater resources are listed in Box 18. The next step is to outline a road map for the implementation of the strategy.
Box 19 illustrates the progress made with disaster management in one of the island states, the Seychelles.