Environmental quality in the coastal and marine environments of Eastern Africa is under increasing pressure from land- and sea-based sources of pollution. Land-derived agrochemical and municipal wastes and sea-based petroleum wastes are the major causes of pollution in the sub-region (Martens 1992, Okemwa & Wakwabi 1993). Residues of fertilizers and pesticides from agricultural inputs in the hinterland enter main drainage systems and are washed into the sea where they have cumulative effects in the marine and coastal environment (Onyari 1981). At the same time, increased siltation resulting from deforestation in the hinterlands also impacts the coastal habitats by increasing the turbidity of the waters, and smothering habitats, flora, and fauna. Eutrophication is not yet a serious issue in the sub-region, but isolated pockets in sheltered bays (especially along the Kenya coast) are threatened with blooms of toxic algae (Wawiye, Ogongo & Tunje 2000) and phytoplanktonic bacteria (Mwangi, Kirugara, Osore, Njoya, Yobe, & Dzeha 2000).
The coastal waters of the Red Sea and Western Indian Ocean are the major sea routes for large petroleum and oil tankers supplying the world with products from the Middle East. Major shipping routes run close to the coral reefs near the port of Djibouti and Port Sudan and ships often discharge oily wastes and sewage. Ships also cause physical damage to the reefs when poor navigation brings them into collision with the reefs (Pilcher & Alsuhaibany 2000). Longshore currents and winds in the Western Indian Ocean are instrumental in the horizontal distribution and spread of pollutants, particularly in bringing oil slicks from the open sea (beyond the EEZ limit) into the coastal waters. In addition to the elevated risk of high-impact oil spills, frequent transport operations also contribute to oil pollution-oil tankers often empty ballast and wash engines on the high seas and residues of degraded oil are consolidated and washed ashore by onshore winds, currents and waves. Tar balls litter beaches with deleterious effects on wildlife and on humans that use the beaches (Munga 1981). Soluble PCBs from these products poison marine life and accumulate in the food web, causing physiological disorders in top predators.
Most Eastern African coastal municipalities do not have the capacity to handle the vast quantities of sewage and solid wastes they generate every day; large volumes of solid and liquid waste are disposed of at sea, or in an unsatisfactory manner, and end up by being washed or blown out to sea where they pose a threat to wildlife and human health
Treated and untreated effluents from municipal, industrial and domestic sources further contribute to coastal and marine pollution. Waste treatment facilities are often poorly designed or sited, and are old and poorly maintained or overloaded. Location of dumpsites and municipal sewage outfalls is therefore critical in maintaining environmental quality (especially water quality, both inshore and offshore) when urbanization and other forms of coastal development increase. (Mwaguni & Munga 1997).
Most Eastern African coastal municipalities do not have the capacity to handle the vast quantities of sewage and solid wastes they generate every day. For example, the Mombasa Municipal Council (Kenya), can handle only 30 per cent of the waste generated (Anon 1996). In Djibouti and Somalia, sewage treatment plants are few in number and are, generally, poorly maintained (Pilcher & Alsuhaibany 2000). Large volumes of solid and liquid waste are therefore disposed of at sea or are disposed of in an unsatisfactory manner and end up by being washed or blown out to sea, where they pose a threat to wildlife and human health. It is evident that a restructuring of waste management policies and plans is required to handle the increase in solid wastes and sewage in the coming years.
Governments in Eastern Africa have enacted public health legislation to regulate responsible environmental use of chemicals. There are also integrated resource management plans aimed at improving land use practices in the hinterland, thereby reducing the incidence and impacts of siltation and eutrophication. Global and regional agreements and treaties are also in place for enhanced cooperation on environmental management in the region. Furthermore, the Nairobi Convention calls for enhanced management of landbased and marine-based sources of pollution, and mitigation of their impacts.
Effective implementation, monitoring, and regulation of activities requires enhanced political commitment and coordination, as well as sustained resourcing. For example, Kenya's National Oil Spill Response Committee should be given legal status and contingency plans should be developed comprehensively. The Kenya Marine Fisheries and Research Institute also requires further financial and human resources to support its research work and monitoring of the coastal and marine environments (FAO/EAF 1999).
Djibouti and Somalia are parties to the Jeddah Convention and members of PERGSA, its implementation agency. Progress in enhancing environmental quality in these countries includes assessment, monitoring and state of the environment reporting, capacity building in oil spill response and integrated coastal management.
ICZM and appropriate legislation and regulations on environmental management are important steps towards the sustainable use of Eastern Africa's coastal zone and resources in the hinterland. There are already national initiatives that should be encouraged by enhanced regional cooperation (Linden 1993, Ngoile 1997, PERSGA 2000). For example, ICZM plans for Kenya and Eritrea use a site-specific approach for the integration of beachfront/seafront developments and waste management in coastal urban centres. Under these plans, location of dumpsites and sewage outfalls will be properly planned and their effects closely monitored.
If success of such initiatives is to be sustained, their institutional structures will need to be strengthened, their coordination improved, and their capacity and funding will need to be increased. Priorities include improved waste management and erosion control in the coastal zone and, in the hinterland, improvement of agricultural practices and introduction of measures such as reforestation schemes, and soil conservation programmes to prevent soil erosion (see Box 2c.3).
|Box 2c.3 Priorities for enhancing environmental quality in Eastern Africa|
|Source: FAO/EAF 1999|