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1.1 Background and Terms of Reference

A decade ago FAO carried out a brief survey of inland water pollution in Kenya, Tanzania, Uganda and Zambia (Thorslund, 1971) from which it was concluded that although water pollution was not then a serious problem in relation to freshwater fisheries, it could become so in the future as a result of increasing urbanization and industrialization. Several recommendations were therefore made relating to legislation, administration, monitoring, training, research and liaison of FAO with other bodies.

The present survey has been carried out to examine the same question in three more countries: Burundi, Malawi and the Sudan, and to review the situation in Kenya, Tanzania and Zambia, as well as to make further recommendations and to report to the fourth session of CIFA in Malawi on 8 12 December 1980.

The terms of reference were:

  1. to identify existing and assess potential future sources of pollution affecting fisheries in the countries listed;

  2. to examine local capacity for dealing with fisheries aspects of water pollution; and

  3. to suggest appropriate infrastructure and establish baselines for future studies and monitoring programmes in the countries.

Some attention has also been given, however, to the impact on fisheries of environmental changes, other than water pollution particularly those resulting from water resource development schemes.

1.2 Acknowledgements

In the comparatively short time available for the mission, it has been possible to contact directly many, but not all relevant organizations and key personnel, and to visit only a few locations and to read but a limited number of relevant documents which has inevitably led to an imbalance in the coverage of different countries. Nevertheless, it is felt that sufficient has been accomplished to gain an overall view of the situation in each of the countries visited and to identify common problems. The consultant is moreover greatly indebted to the many individuals (listed in Appendix 1) with whom he has had invaluable discussions and exchange of information, and considerable help in arranging his itinerary. This report was circulated in draft to all those listed in Appendix 1 as well as other participants to the Fourth Session of CIFA and comments taken into account in preparing the final document.


2.1 Freshwater Fishery Resources

In most of the countries visited, fish provide a substantial proportion of the animal protein supply in the diet, amounting on average in 1972–74 to under 20 percent in Kenya and the Sudan, 20–24 percent in Burundi, Tanzania and Zambia (FAO, 1980) and, from a more recent figure, 60–75 percent in Malawi (Mothotho. pers. comm). Obviously the importance of fish as a source of dietary protein varies within countries. It is particularly important, for example, in Khartoum, compared with the rest of the Sudan, and also, in Tanzania, in the region near the shoreline of Lake Victoria, compared with areas further inland as reflected by the better nutritional state and greater resistance to disease of children under five years old. And in Zambia recent figures show that fisheries supply about 50 percent of the protein in towns and up to 60 percent in rural areas; per caput consumption can exceed 25 kg/year in the north near the lakes and along the Kafue and Zambezi rivers (Williams, 1977), and in the Luapula Province it has been estimated at as much as 45 kg/year by the World Health Organization (see Muncy, 1973).

Most of the fish in all the countries visited comprise freshwater species, the proportion being over 80 percent in Tanzania, 90 percent in Kenya, 95 percent in the Sudan and 100 percent in Burundi, Malawi and Zambia (Welcomme, 1979). Altogether it amounts to about 358 000 tonnes live weight/year, which is over 25 percent of the total catch of freshwater fish in Africa; the figure could well be an understimate because the catch from subsistence fishing on small rivers and other waters may enter the diet directly and therefore not be recorded.

Potential catches of fish in some of the countries visited are higher than present values - by estimated factors of 1.4 for Zambia, 1.6 for Tanzania and 5.5 for the Sudan quite apart from any increase to be expected from presently unstudied and unexploited resources, as must be the case for example in the rivers of Burundi, as well as from the development of aquaculture in all countries.

The importance of fish protein is particularly great in other countries, such as Kenya, whose meat production at present is actually declining and a food shortage is anticipated (African Business, 1980), and in Tanzania where there is a widening margin between food production and demand.

This brief resume serves to indicate the magnitude and importance of the fishery resources that might be at risk from water pollution and other environmental changes, although the actual risk will depend upon the interaction of several factors, as discussed later (Sections 2.2 to 2.5); but most important is the distribution of exploited fishery resources within each country in relation to the distribution of water pollution.

2.2 Demography

In general the risk of water pollution would be expected to increase with population density and growth. Table 1 underlines the low population density in the countries visited, compared with many developed countries.

Table 1: Demographic characteristics of selected African countries (FAO 1978)

Population Growth
Kenya  23 4.1*
Malawi  96 3.1*
The Sudan    73.5
Tanzania      20**  3.3**
Zambia    73.1

*   Based on latest census
** Average (Ministry of Finance and Planning, 1980)

This would lead to a generally low expectancy of water pollution; although much would depend upon the degree of urbanization, and also the extent of industrialization, amount of water available for dilution of waste waters and degree of waste water treatment provided, as well as future trends in all these factors.

In the Sudan, for example, the population is low in density, but tends to concentrate along the Nile and its tributaries. In Kenya it has been forecast (Ngunya, 1975) that between the years 1980 and 2000, the urban population will grow from 17 percent to 40 percent of the total. In Burundi, on the other hand, although the population density is the second highest in Africa, 96 percent of the people are scattered in rural areas in autonomous family units on small plots of land, rather than being concentrated in towns and villages; however, efforts continue to be made to resettle many of them in the Ruzizi valley, draining to Lake Tanganyika. In Tanzania, over 90 percent of the population is rural but there is a drift to the towns, as shown by the latest census figures (Ministry of Finance and Planning, 1980). A similar drift is found in Malawi. In Zambia, only about 66 percent of the population is rural and the density is particularly high (41.6/km2) in the copperbelt (Chidumayo, 1979).

Noteworthy is the high rate of increase in population in all the countries, especially Kenya where a low-key birth control programme is reported as being rather ineffective, the response being poorest in rural areas (Mbote, 1979). In Tanzania, rates of annual increase are 2.8 percent in rural areas and about 6 percent in the towns (Ministry of Finance and Planning, 1980); in Zambia the figures in 1974 were 1 percent and 7 percent respectively (Chidumayo, 1979) and are now about 1 percent and 9 percent respectively. In all the countries visited the rate of growth is accelerating.

It is clear, therefore, that urbanization, although not yet highly developed, is increasing and is likely to continue to do so in the immediate future, especially with the current high and accelerating rate of population growth.

2.3 Agriculture

The importance of agriculture to the countries visited can be illustrated by expressing the agricultural gross domestic product (GDP) as a percentage of the total GDP; the figures show that, except for Zambia (11 percent), all are highly dependent upon agriculture, the situation being similar in Kenya (27 percent), Malawi (33 percent) and the Sudan and Tanzania (34 percent), while Burundi (59 percent) is an extreme case (FAO, 1978). Such emphasis on agriculture might lead to a low expectancy of water pollution, but much depends upon the intensity of agricultural practices, particularly the extent of monoculture and heavy application of pesticides, and their proximity to fisheries.

Pesticides used in developing countries include certain chemicals that, for environmental reasons have been partially or completely banned in developed countries, but for which effective cheap substitutes have yet to be evolved. Usage in developing countries is increasing, it having been estimated to be 20 percent of the world total in 1972 and to increase to 36 percent of the total by 1985, amounting then to 846 000 tonnes (Stout et al., 1979). In (13) African countries, the bulk of the materials used are insecticides, half of which are used on cotton, but the proportion of herbicides used has increased from 3 percent of the total in 1971 to 18 percent in 1975, while that of fungicides has remained below 1 percent (Stout et al., 1976).

Direct and indirect contamination of water by agricultural chemicals, especially pesticides may cause, for example, fish kills, reduced fish productivity and elevated concentrations of undesirable chemicals in edible fish tissues. This question is considered again separately in Section 3.2 for each country visited.

Agricultural practices can also impinge on fisheries in several other ways. Soil erosion and the resultant increases in concentration of suspended solids, for example, can reduce photosynthesis and the productivity of fish species that are not adapted to turbid waters; such a phenomenon seems to have occurred in Lake Baringo in Kenya and there are fears expressed that it might also occur in parts of Lake Victoria (Meadows, 1980). On the other hand, increasing the supply of nutrients in drainage water can result in increased total fish production, perhaps at the expense of species diversity.

In all the countries visited, agriculture is being further developed, which will lead to an extension of existing industries involved in the processing of animal and plant products, and an increase in the discharge of wastes, most of which are highly oxidizable, often containing high concentrations of suspended matter, and occasionally contaminated with toxic inorganic chemicals. These sources of water pollution are discussed again in Section 3.1.

2.4 Forestry

Over-exploitation of forests which has been extensive in the countries visited, and has led, amongst other causes, to severe land erosion, and presumably also to changes in the discharge characteristics of the rivers, is generally recognized as a problem in need of urgent attention at all levels. In Tanzania, for example, there is national concern, expressed in the press (Daily News, 1980) in strong appeals to plant trees, and government schemes make trees available for planting free of charge; in Burundi there is a national programme for reafforestation; in Kenya there are plans to treble tree planting in the next 10 15 years. Alongside some of the schemes, however, there are also plans for further forest exploitation and for the construction of paper mills, e.g., in Kenya, Malawi and Tanzania which introduces the potential for further water pollution (discussed further in Section 3.1).

2.5 Water Resources and Industrial Development

In most countries there are national water plans directed principally to supplying potable water to a greater proportion of the population. Development of piped domestic and industrial supply can bring with it the increased risk of water pollution from water-borne sewage and industrial waste. In Kenya, for example, it is planned to supply the whole population with tap water within 1 km of their homes by the year 2000; this contrasts to the situation in 1972 when only 19 percent of the total population and 9 percent of the rural population was so served, and to the situation then projected for the year 1980 when the corresponding figures were 31 percent and 19 percent respectively (Ngunga, 1975). In this case there are also plans for sewerage, where necessary, and for sewage treatment.

In Burundi, with only 4 percent of the population living in urban areas, only about 10 percent of the population is now served with potable water supplies, but it is planned to increase the figure to 50 percent within the next decade (REGIDESO, 1980), given the development of village communities and the resettlement of some people in the less populated areas. The consequence will be an increase in urban sewage, particularly in Bujumbura, where it currently discharges untreated to Lake Tanganyika, either directly or indirectly via the river Ntahangwa. Sewage treatment facilities are planned for the future, following completion, perhaps within five years, of storm sewers which are considered the first priority.

In Tanzania, the rural population has already been gathered into villages to some extent, to which it is planned to supply water by the year 1990, though this is unlikely to increase water pollution problems significantly. However, supplies to urban areas are also being actively pursued.

The construction of dams for water resource development can result in damage to fisheries for while they may provide productive fisheries upstream as in the case of the Sudan, they may also lead to an overall reduction through loss of highly productive fisheries in the flood plains downstream which otherwise would have provided the major portion of the river catch. In the Rufiji basin in Tanzania, for example, hydro-electric development is likely to have a marked effect on fisheries; an initial appraisal by FAO has included recommendations for further studies to be carried out by the Rufiji Basin Development Authority, in collaboration with the Zoology Department of the University of Dar es-Salaam, which has already been active in the area, and for the drawing up of a programme in collaboration with the Tanzania Fisheries Department, the University, UNEP and FAO (Hopson, 1979).

The lack of fish ladders on some of the more recently built dams has led to the occurrence of fish mortalities under conditions of low river flow in the Sudan and to interfere with the upstream migration of fish in Kenya. And in the Sudan, there is also the possible future impact on the flood-plain fisheries, of cutting the Jonglei Canal through the centre of the flood-plain area (Muller, 1978), a scheme considered by some to have been implemented before sufficient basic data on the existing situation had been gathered for a proper environment impact assessment to be made.

Hydro-electric development is likely to be linked to the use of power for the development of industry and thus to the increased risk of consequential problems of industrial waste disposal. At present, industrialization in Africa is low as judged crudely by the per caput consumption of energy, expressed as kg coal equivalent/year for 1976; the figures are 11 for Burundi, 56 for Malawi, 68 for Tanzania, 152 for Kenya, 167 for the Sudan, and 548 for Zambia (FAO, 1979). This may be compared with figures of 5 000–10 000 for developed countries. Industrialization is likely to increase in Africa and estimated and projected per caput consumption of energy indicates that by the year 2000, the figure for developing countries will be similar to that of the developed world at the turn of the century (Stout et al., 1976). One would therefore expect that, in general, industrial water pollution problems in Africa would be and would remain, on a relatively small scale in the immediate future, though this does not rule out the possibility of severe local problems. These are examined in more detail in Section 3.1.

2.6 Conclusions

A brief consideration of some of the factors relevant to fisheries and pollution in East Africa, with some specific references to the six countries that have been visited, leads to the following conclusions.

  1. Freshwater fisheries are very important as a source of dietary protein and are likely to become even more important in the future since, in several countries, there is already a gap between demand and supply of home-grown food, a gap that is likely to increase with the current very high rates of population growth. The protection and development of fisheries is thus essential.

  2. Agriculture plays a vital role in the economy and is likely to be developed further, partly with the help of increasing quantities of insecticides and also herbicides; this development is of considerable concern to fishery interests because of the risk of accidental damage to fishery resources (which is discussed further in Section 3.2). In addition, the processing of agricultural products may lead to the discharge of highly oxidizable wastes and the reduction of concentrations of dissolved oxygen in receiving waters (which is discussed further in Section 3.1).

  3. The adverse effects on fish of deforestation may be avoided or rectified by the reafforestation schemes that are planned, but some of them are also linked to the development of a pulp and paper industry, the wastes from which also pose a threat to fisheries (see also Section 3.1).

  4. Urbanization though at present not generally developed, is increasing and bringing with it an increase in piped water supplies and consequent water borne sewage disposal.

  5. Schemes for water resource development often centre on hydro-electric power production, as a consequence of which flood-plain fisheries may be especially at risk. In addition, the availability of power, which shows signs of being increased in several countries, provides the thrust for fulfilling industrial development, which involves the disposal of more waste waters (as discussed further in Section 3.1).


Pollution control legislation, and the administrative and scientific work devolving from it, are so intimately bound up with the nature and extent of pollution problems affecting fisheries in each country that the two aspects are dealt with together, country by country, separating as far as possible the legislation and its enforcement, from present and future problems. First, sewage and industrial wastes, and then pesticides are considered separately. But there follows a final section in which factors of common interest to all countries, as well as topics of interest to only a limited number, are discussed, particularly in relation to needs for the future and role CIFA might play.

3.1 Sewage and Industrial Wastes

The reports in this section are presented, arbitrarily in the order in which the countries were visited.

3.1.1 The Sudan

The Ministry of Health enforces a National Water Pollution Control Act whereby the discharge into the River Nile and its branches of sewage whether treated or not is prohibited; the discharge of treated industrial effluent is permitted in exceptional cases, provided it contains “no toxic chemicals. suspended solids not more than 30 mg/l and BOD [biochemical oxygen demand] not more than 20 mg/l” (George, 1976). The Ministry carries out routine monitoring using normal sanitary analyses but there is a dearth of data on heavy metals and pesticides. Also, the Fisheries Administrative Department enforces provisions of a Fisheries Act designed to protect and safeguard aquatic life (George and El Moghraby, 1978).

In rural areas domestic sewage is removed and dumped to dry in remote areas or, more commonly nowadays, passed into septic tanks and soakaways, and so presents no hazard to fisheries.

In the larger towns sewage is collected in foul sewers and treated in either percolating filters or oxidation ponds. The sludge may be used as agricultural fertilizer and the effluent, after dilution, used to irrigate trees or, if containing a high proportion of industrial waste, passed to the desert. Thus there appears to be no risk to fisheries or fish consumers, unless as apparently happens, fish that occur in effluent channels are caught despite laws prohibiting such fishing.

Some industrial wastes have been or are discharged to the River Nile, and while this is regarded in some quarters as unsatisfactory, there is no evidence that fisheries have been damaged by the practice, and the Fisheries Department is satisfied that no serious problems derive from these sources at present. Furthermore, future industrial development on the River Nile has been considered not to pose a serious threat (George, 1976).

It has been suggested, however, that the law needs strengthening and that additional resources should be made available to enforce it more rigorously and carry out monitoring. The need for a complete inventory of discharges has been stressed and the University of Khartoum plans to carry out such a survey for both the Blue and White Nile over a three-month period in 1981 with the help of an overseas expert.

Further major industrial development may well take place mainly on the coast, e.g., at Port Sudan, rather than inland, where in any case it would appear to be unlikely to have much effect on the Nile provided current methods of water disposal prevail.

In the Gesira area there are some pesticide formulation plants, but they produce no effluent discharges, and emergency retaining walls minimize the likelihood of water pollution resulting from accidental spills. Conclusion

There are no serious problems of water pollution affecting fisheries at present, partly because much of the sewage and industrial waste is not discharged to the Nile, which in any case provides a large amount of dilution. However, there is a lack of information on discharges to the river and on their effect on water quality. Furthermore, the legislation may need strengthening.

3.1.2 Kenya Legislation

The anti-pollution legislation in Kenya has been touched upon by Moore and Christy (1978) and given in more detail, with comments and suggestions for improvement by Meadows (1980). Most important is the Water Act 1951, whereby all prospective water users must apply to the Water Apportionment Board for a licence to abstract, and must satisfy it that any effluent discharges will meet standards of quality necessary to protect downstream uses, including fisheries. The Board comprises members of various ministries, including those of commerce, industry and agriculture, specialist regional catchment agencies, and members of the public, and has informal contact with fishery interests; the Board is advised by the Director of the Water Department of the Ministry of Water Development. Failure to comply with a condition of consent can result in the revocation of a licence, subject to appeal to the Ministry of Water Development. This is a very powerful provision. Enforcement of the Act is accomplished by the Ministry of Water Quality and Protection Control Division (established in 1972) together with the Trade Effluent Inspectorate. A revised act, tightening up loop-holes discussed by Meadows (1980), relating to the control of discharges to municiple sewers, is expected to become law in 1981.

Effluent standards are based on relevant water quality objectives for specific uses, taking account of the assimilative capacity of the receiving water. In the absence of data on water quality criteria for African or similar freshwater species, the requirements of trout are used as a guideline. The Ministry has facilities for carrying out toxicity tests on effluents using fish, which it has used from time to time. In setting effluent standards, Baker and Meadows (1978) favour methods based upon dilution, toxicity, stream physics and, to avoid unnecessarily stringent standards, water usage downstream, although in most cases this is taken to be usage for domestic consumption. For seasonal streams, off-river storage is envisaged for some effluents, with discharge being allowed only at times of high river flow.

Specific advice is given on the design and operation of plant, both for production processes and effluent treatment, so as to facilitate the attainment by industry of the effluent standards being required. Special emphasis has been given, for example, to the treatment of wastes from the processing of coffee, the advice being developed in cooperation with the Kenyan Institute of Industrial Research and the industry concerned, i.e. the Kenyan Coffee Board in this case.

To help ensure that effluent standards are met, it has recently been proposed that the legislation should be strengthened to give power to the government, inter alia to specify production processes and pollution control equipment and to provide subsidies for its purchase and installation (Kenya, National Environment Secretariat, 1979).

For the centralized treatment of effluent in large urban areas, Baker and Meadows (1978), as well as Mbote (1979), stress the appropriateness of waste stabilization ponds, together with the possibility of using them for fish production (a use being investigated by Kenya as part of an international programme sponsored by the International Development Research Centre); they also point to acceptable alternatives to water-borne sanitation in small urban and rural areas.

The Department of Fisheries has no special powers and responsibilities regarding the protection of fisheries from pollution but has an interest and is represented on an inter-ministry committee on pollution.

Until now, pollution control has been exercised largely by central government but there are now plans for more decentralization at a provincial and district level (Kenya, National Environment Secretariat, 1979). National coordination of environmental protection

The environmental implications of water resource development in Kenya have been discussed by Baker and Meadows (1978), and they emphasize the necessity to consider the subject on a catchment basin basis within a national context, and in relation to all other interests and developments. They (and others) stress the need, for example, for coordination between those responsible for water supply and those responsible for the location of industry. Now, there are several new bodies in Kenya concerned with developments in river basins, e.g., the Lake Basin Development Authority, covering the eastern part of Lake Victoria, the Tana River Development Authority, and the Kerio Valley Development Authority, though, as yet there is not complete coverage of the whole country in this way. Some schemes, involving the possible transfer of water between catchments, call for the close coordination between the relevant local and national authorities.

Overall planning of national development and environmental protection is undertaken by the National Environment Secretariat, a small unit atached to the Office of the President. Its duties and functions and accomplishments are set out in broad terms in Appendix 2 and there are now proposals to establish it by statute and provide it with regulatory powers (Kenya, National Environment Secretariat, 1979). Included amongst its presently envisaged future priorities are the forecasting of environmental trends, including the quality and quantity of water, a review of existing environmental law, and development of a procedure, with legal backing, for the assessment of the environmental impact of new projects. Pollution problems affecting fish

After a long period without serious water pollution problems, save for those in the Nairobi river, several serious pollution incidents developed in 1970, soon after which a survey of the concentration of dissolved oxygen in all the major rivers was carried out by the World Health Organization and an inventory made of all sewage works and industrial discharges (Ngunya, 1975). This, together with data on river flow from the Ministry's hydrology sector, has since proved invaluable in the setting of effluent standards for which research has also begun on self-purification processes in rivers.

The nature and extent of pollution problems affecting freshwater fisheries in Kenya have been summarized by Ngunya (1975) and Arunga, Okemwa and Nyaoke (1978). In general they are not regarded as seriously damaging to fisheries, although there is concern for the future. The main sources of potential pollution are sewage and other oxidizable wastes from food processing plants, especially for coffee and sugar refinery, pulp and paper mills, textile mills and tanneries. There are also localized discharges of heavy metals and a unique problem caused by high concentrations of fluoride. All these sources are being actively considered by the authorities; work has been carried out for example on the design of oxidation ponds; there is growing interest in using sugar refinery waste for ethanol production; studies have been commissioned on the toxicity of dyes used in the textile industry; and consultants have examined the problems with effluent containing fluoride. In the last two years there has been an upsurge of chemical and metal-based industries (Baker and Meadows, 1978) and although heavy metal pollution is not as yet a major problem the recent increase in the number of tanneries is posing the problem of chromium pollution; the authors also report that pesticides are manufactured at these locations, a situation that requires careful surveillance - indeed the existing monitoring strategy, though sound, is considered in need of extension if pollution problems are to be contained. As yet there is no automatic continuous monitoring carried out.

Industrial production in Kenya is certainly expected to rise (Kenya, National Environment Secretariat, 1979; Mwamanga, 1980), perhaps by 10 percent/year, and by the year 1986 it is planned that its contribution to the GNP should equal that made by agriculture. Some industry is supported by the Government, and steel is considered a possibility for the future. Conclusion

The development of acute local pollution problems a decade ago was followed by country-wide acquisition of data on water quality and waste discharges and the strengthening of the pollution control authority's existing legislation. Considerable attention was focussed on the waste from coffee processing, in collaboration with the industry; and in spite of major improvements, following the introduction of recycling of water within the factory, it still remains the largest single source of water pollution. Decentralized water pollution control is to be developed further and the legislation is being revised. At the same time steps are being taken to give statutory authority to a small National Environment Secretariat which has responsibility for coordination of national development and environmental protection.

3.1.3 Burundi

In Burundi there is a general fishery law to prevent water pollution, but apparently no government department with special responsibility for its enforcement. Nevertheless, there is now government concern expressed about the discharge of sewage and industrial wastes to Lake Tanganyika and long term plans to provide sewerage and sewage treatment facilities for the capital, Bujumbura, and ultimately to connect industrial discharges to the foul sewer. These plans are being formulated and coordinated by Regie de Distribution d'Eau et d'Electricite (REGIDESO, 1980), an inventory of all industrial discharges (which include those from the manufacture of beverages, shoes and soap) while the Departement de l'Assainissement, with the help of REGIDESO, is taking the initiative in considering trade effluent treatment and effluent standards. However, the main activity of the Departement for the immediate future will involve the setting up of the organization itself, rather than carrying out technical appraisal and management of pollution problems; thereafter, more technical resources will be required to deal effectively with the situation and a couple of outside experts are soon to join the team. The initial concern in setting effluent standards for industrial wastes is to protect biological treatment processes rather than water quality in Lake Tanganyika, although no decision has yet been made whether to use lagoon treatment or a more sophisticated method. Hitherto, there has been no formal consultation with fishery interests, though this is not ruled out for the future.

In the meantime, industrial development is taking place in Bujumbura, e.g., the establishment of a tannery and a textile mill, before the sewerage system is available and more of such premature development is expected in the future; there are long-term plans (Burundi, 1978) to increase labour-intensive production, to develop nickel resources if possible, to develop peat for fuel and also to increase hydro-electric generation in the north. Conclusion

There are plans for sewage and industrial waste treatment facilities and an administration is being set up capable of preventing and controlling pollution but industrial development is already taking place.

3.1.4 Tanzania Legislation

The Fisheries (General) Regulation, 1973, made by the Ministry of Natural Resources and Tourism under the Fisheries Act 1970, enables water pollution affecting fisheries to be controlled, and some ad hoc work in that direction has been carried out by research staff of the Ministry's Fisheries Division. Guidelines on effluent standards have been prepared by a government-established Effluents Standards Committee (Tanzania, Ministry of Health, 1977) and its recommendation that they be given legal backing is currently being pursued. The Committee recommended that there should be a government review of legislation relating to environmental protection and that the Ministry of Lands and Urban Planning (the custodian of UNEP affairs in Tanzania) should take the initiative in forming an Environmental Pollution Control Authority whose secretariat should be located at State House or the Office of the Prime Minister and whose proposed responsibilities would initially be confined to water pollution control.

In the event the Ministry of Lands and Urban Development formed a Tanzanian Environment Management and Protection Unit with responsibility inter alia for pollution control and the coordination of all environmental matters; it seems likely to concentrate its attention first on water pollution. A new Effluents Committee was also set up, in the absence of a more appropriate body, by the Tanzanian Bureau of Standards, an independent body established in 1975. This Committee began work in May 1979 to consider inter alia the possibility of studying methods for testing the toxicity of effluents to fish, a subject not dealt with in the Ministry of Health report, although currently under very active consideration by the International Standards Organization which Tanzania has recently joined.

The Ministry of Water, Energy and Minerals, through its Principal Water Officer, is responsible for issuing water rights under the Water Utilization (Control and Regulation) Act 1974, and generally adopts the Ministry of Health Guidelines, while the separate Ministry of Lands, Housing and Urban Development, through its Sewage Division, established in 1978, deals with new urban sewage schemes. including standards for discharges to the sewers but not rural developments, even if they involve industrial waste disposal. This division of responsibilities between the two ministries calls for close collaboration between them.

Neither Ministry has the resources available at present to check that effluent treatment plants are operating properly and that the standards set for the effluents are being met satisfactorily by industry. Recently (July 1980), fishery research has become the responsibility of a new autonomous Fishery Research Institute, having several centres, though still answerable to the Ministry of Natural Resources and Tourism, but it does not have the resources, either, to carry out the necessary monitoring. Clearly the pollution control legislation and the means of implementing it have yet to be finalized.

In a very detailed report (Alkbrant, 1979), commissioned by the Ministry of Water Development, Energy and Minerals to advise on rural water supplies, existing legislation dealing with water quality was reviewed and recommendations made regarding: (i) amendment of the Water Utilisation Act to enable it to cover the setting of effluent standards; (ii) extension of existing surveillance of drinking water to cover sewage and industrial effluents and receiving waters; and (iii) the setting up of a river-basin-oriented infrastructure, with priority given to heavily populated industrial areas. Although dealing primarily with drinking water, its recommendations are equally pertinent to the protection of fisheries from water pollution. The report also examined the capacity of existing laboratory resources to carry out the necessary monitoring and dealt with training needs.

An aspect not covered in the report was the need for, and ability of, government organizations to give technical advice on the most appropriate means of waste water treatment necessary to achieve the effluent standards demanded. Neither the Ministry of Lands nor the Ministry of Water currently have the capacity to fulfil such a role, although both (and others) agree it would be invaluable in water pollution control. A Tanzanian Industrial Research and Development Organization, established under statute in 1979, has included in its functions: (i) advice to industry on minimizing sources of pollution; and (ii) research on abating and prevention of pollution, and it may well be able to help in the future.

The report (Alkbrant, 1979) also considered effluent standards, a preference being expressed for those that took account of available dilution and local circumstances, something that seems to be generally preferred to those that are uniform in all circumstances. It also proposed the setting up of a central National Water Quality Committee which would be a coordinating and policy-making body comprising representatives of all interests, though fisheries interests were excluded, presumably because the report was mainly concerned with drinking water.

There are regional plans for water development, based upon catchment and political areas, and provision has recently been made to coordinate them at national level. The formation of new National Urban Water Authorities to deal with water supply in urban areas is being actively considered, but their likely lack of responsibility for sewerage and sewage treatment is considered by some to be a serious disadvantage. National coordination of environmental protection

A more recent report (McAuslan, 1980) commissioned by UNEP at the request of the Government of Tanzania discusses the control of all environmental pollution in the light of existing legislation and institutions, and the setting up of a National Environmental Agency, which should be a small new organization, established by law under the aegis of the Ministry of State for Economic Affairs and Planning. Its possible composition, terms of reference and programme are outlined. Essentially it would be a planning and administration agency with strong political backing and a brief to ensure the implementation of a national environment policy and programme. Its priorities would include: (i) pollution control techniques and standards for industrial, mining and energy developments; and (ii) the environmental implementation of major irrigation programmes. While stressing the urgency of the matter, the report also stressed the need for cost/benefit analysis of environmental protection action or inaction. Nature and extent of problems affecting fisheries

In Tanzania industry is already well established in several of the larger inland towns, having increased during the 15 year period to 1978 (Ngoile, Challe and Mapunda, 1978). Although most of the existing industries have been set up without pollution controls (Tanzania, Ministry of Health, 1977), the Ministry's Effluent Standards Committee's guidelines are now being used by consultants in current proposals for sewage and industrial waste treatment facilities in towns such as Arusha, Morogoro, Moshi and Mwanza; in most cases town master plans for future development exist, and include details of existing and proposed industries, but none is yet implemented.

The location of new industry is dealt with by a National Development Corporation and other autonomous industrial corporations under the Ministry of Industry, not necessarily with reference to the availability of water supplies, a lack of coordination which has been highlighted and heavily criticized (McAuslan, 1980) and underlines the need for integrated planning.

Since the report on the nature and extent of water pollution problems in Tanzania (Ngoile, Challe and Mapunda, 1978), there have been further development, e.g., of textiles and tanneries, in existing industrial areas, the policy being to achieve a fairly even distribution of zoned industrial complexes throughout the country. Hitherto, most industry was located on the coast but now there is a new trend, as gauged for example by an increase in the energy consumed by industries inland, the percentage of the total energy consumed having increased from 17 percent to 30 percent over the period 1967 to 1979 (Msuya, 1980). However, new waste treatment facilities have been provided for some existing inland sources of pollution, e.g., for raw sewage, previously discharged direct to Lake Victoria at Mwanza, and for the waste from a tannery recently established there, and for the waste from a new textile industry at Musoma.

Although there is no evidence of serious adverse effects of waste discharges on fisheries, no scientific studies have been carried out, and there is concern that fish in Lake Victoria are at risk from the further increase expected in industrial waste production, especially those such as Tilapia spp. that live close inshore.

Despite a shortage of trained technicians to support a research programme, studies are planned by the Fisheries Institute to measure the toxicity to indigenous fish of industrial effluents presently discharged to Lake Victoria, with a view to taking remedial measures. However, in those cases, identification of the chemical causes of toxicity would depend upon receiving help from the Government Chemists' Laboratory of the Ministry of Health, which too is presently below complement.

There is major development in the Rufiji river basin which includes a large paper mill on the North Ruaha River draining into a very important flood plain fishery which has aroused considerable concern (Bernacsek, 1980; 1980b); the need is foreseen there for effluent quality monitoring using tests for toxicity to indigenous fish. And further downstream there are plans for large hydro-electric developments, the power from which may well be partly utilized by industry in the future. An iron industry is planned for Njombe in five years' time, as well as a steel-rolling mill for Mwanza. Conclusion

Industrialization has been increasing, especially inland, although new waste water treatment plants have been provided for existing and new sources of pollution. Water pollution does not seem to be a serious problem yet, but no studies have been carried out to investigate the question and there is fear that fish nursery grounds along the shores of Lake Victoria may already be adversely affected. There are plans to carry out toxicity tests on effluents being discharged to the lake, using indigenous species of fish. Provisional guidelines on effluent standards are being used for pollution control but the legislation is considered to be in need of revision. A capability of administering it effectively, particularly with regard to monitoring of effluent quality, needs to be established. There have been constructive proposals to set up a small national coordinating body for water quality and environmental protection.

3.1.5. Zambia Legislation

The anti-pollution legislation in Zambia has been touched upon by Moore and Christy (1978). The Directorate of Water Affairs of the Ministry of Agriculture and Water Development, through a Water Board representing many relevant interests, now licenses the abstraction of surface water, under the Water Act, Ch. 312, and can impose conditions relating to any likely consequential water pollution; however, its powers are limited and it has at present no capability for the routine monitoring of effluent and river water quality, though it investigates pollution incidents. Municiple authorities are responsible for urban water supply, the control of waste discharge to sewers and sewage treatment, and have facilities to carry out regular monitoring. There is consultation with fishery interests though this is not obligatory.

The Mining Regulations 1971 provide for the control of water pollution from mining, but regular monitoring is carried out only by the mining companies themselves, though the results are required to be sent to the Directorate of Water Affairs.

The Natural Resources Conservation Act of 1970 provides, in general terms, for the prevention of pollution and also for the setting up of a Natural Resources Advisory Board for soil, water, flora and fauna.

The Ministry of Commerce registers the establishment of industries though there is no obligation to consult those concerned with water supply and fisheries.

There is general agreement that the present legislation and infrastructure are inadequate, and consequently there have been several initiatives taken to try to improve matters. A government Water Pollution Research Committee, set up in 1972, prepared draft proposals in 1978 to amend the Water Act to deal more comprehensively inter alia with effluent standards and monitoring; these are being considered by the Directorate of Water Affairs. The Committee recommended that provisional standards, prepared by the mining industry (Charman, 1978; see also Kaoma and Salter, 1979), should be accepted as guidelines by the Government. In 1977, the Ministry of Lands and Natural Resources began preparing an Environmental Conservation Act dealing, amongst other things, with pollution, which it is currently broadening. The Ministry of Commerce which had apparently been given a brief for pollution control has since commissioned a study (Kratel, 1979), relevant to the drafting of a new Water Pollution Control Act, which includes guidelines on effluent standards and water quality criteria for fish; the report has been circulated widely for comment. There seems to be general agreement in favour of standards that allow for local conditions, such as dilution. National coordination of environment protection

The National Council for Scientific Research through a special research committee examined the question of environmental pollution in 1974–75, and recommended legislation and the setting up of an overall body independent of existing organizations, which would be responsible for policy and monitoring.

Recently it has been agreed, at a meeting of all those concerned, that the Ministry of Land and Natural Resources should now coordinate all activities on the revision of legislation. However, there remains the question of government agreement on guidelines for effluent standards and it is not yet clear how they will be established and incorporated into law; the Fishery Department feels that outside expert advice is required regarding standards for fish, pending the outcome of experimental work in the resistance of indigenous species of major importance to contaminants relevant to rivers in Zambia. A capability for carrying out toxicity tests on effluents, using fish, is also seen as a necessary development for effective pollution control in the future, as well as the ability to investigate the accumulation of chemicals in fish and to use biological methods of water quality surveillance. Furthermore, it is generally agreed that there is need for the acquisition of government expertise on waste treatment technology and on the self purification capacity of the Kafue river, the river under greatest threat from water pollution. Nature and extent of problem affecting fisheries

Mumba, Chanda and Muleya (1978) have indicated that water pollution from sewage and industrial wastes in Zambia is concentrated in the Kafue river in both its upper reaches, where it is associated particularly with copper mining and urban development, and in its lower reaches and tributaries, from Lusaka and especially the industrial estate at Kafue, which includes textiles, nitrogen fertilizers, plastics construction, yeast manufacture and a tannery. They concluded that generally pollution was not yet a severe problem, although there was a lack of detailed studies on the impact of waste discharges on aquatic life, and the situation was barely under control. Downstream of the mining area fish kills have occurred and catches over a 10 to 15 km water stretch of the river are said to be very low. In terms of concentration of various water quality characteristics, including dissolved copper, pollution has decreased during the period 1971–78 (Kaoma and Salter, 1979) and data from June to December 1979, provided by the mining companies (J.A. Charman, pers. comm.) show further reductions compared with the same months in previous years. However, no data are available on the effect of copper and other water quality characteristics on local species of fish although a little is known of the dissolved oxygen requirements of some (Chapman et al., 1971). Fish kills have also occured in the river downstream of Kafue and particular concern has been expressed (e.g., by Kaoma and Salter, 1979) about the impact of nitrogen wastes from Kafue on eutrophication in the river and its possible exacerbation of the low concentration of dissolved oxygen already normally experienced during the two periods of flooding during the year. The question has not yet been investigated however.

Recent developments include the establishment of two paper mills and the possibilities of establishing a steel roller-mill.

The policy for industry in the future, within the plan for 1979–83, is to invest proportionally less in mining than hitherto, especially for copper (which, however, will still remain predominant) and to develop non-copper minerals, develop more energy from coal and also establish small-scale industries including those based on copper, as well as those for processing agricultural products such as sugar, the output of which is expected to increase. Conclusions

There is considerable urban and industrial development on the Kafue river, and evidence of adverse effects on fish in the upper reaches in the copper belt, as well as in the lower reaches near the industrial estate of Kafue; nationally, the problems are not regarded as severe, but no detailed studies have been carried out to investigate them. The authorities do not have the capability for regular monitoring of effluent and river water quality and at present rely on the mining companies to fulfil this role near the mines. The pollution control legislation is generally regarded as unsatisfactory and its revision is being actively considered, together with proposals for national coordination of water pollution and environmental pollution control.

3.1.6 Malawi

The control of discharges into natural waters is carried out by the Water Resources Board of the Department of Land Valuation and Water under the Water Resources Act 1972. Application to abstract water has to be made to the Board which can impose conditions on consequential effluent discharges. Provisional guidelines on effluent standards relate to BOD, suspended solids, total dissolved solids, and toxic substances as a general class. Charges for water use are levied, according to water use and the class of recipient water (lakes, potable use, and use for fisheries all have the highest rating), the extent to which the effluent deviates from the standards, the quantity of effluent (to encourage economy in water use and restrict effluent volume) and the dilution available under dry weather flow conditions (considered in addition to quantity of effluent); self purification processes in streams are not yet taken into account explicitly (see Appendix 3). One of the advantages of the charging system is that it applies to rural as well as to urban districts.

Sewage treatment and disposal is the responsibility of local councils who have the power, under the Public Health Act, to control the discharge of industrial waste into the sewers; sewage discharges are controlled in turn by the Board.

A UNDP team presently considering a water resources master plan for Malawi is to be joined by a legal expert in 1981 to advise on a review of the water legislation. Schemes for sewage disposal are not, at present, automatically linked to such a plan, but water development in rural areas is not expected to result in a significant increase in water borne sewage disposal, and even in some of the towns, the septic tank is thought likely to retain its importance.

Currently there are plans to build up technical expertise in the Water Department to achieve more extensive effluent quality control and monitoring, using central and regional laboratories, one of which is soon to be operational at Blantyre. The greatest need is for personnel who have received relatively short-term (three to six months) intensive training. More expertise would be desirable on self-purification processes in natural waters, so that these could be taken into account in effluent standards, the formulation of water quality objectives for specific water uses, and industrial waste treatment technology; it is stressed, however, that the latter should not be acquired to offer a consultancy service to industry, but simply to provide an insight and understanding of the possibilities and limitations of process and waste-water treatment control and, in dealing with industry, to be in a position to offer informal advice if need be.

Magasa (1978) has outlined water pollution in Malawi and concluded that it was not yet a serious problem, treatment facilities being available for sewage in urban areas and there being little industrial development, mostly centred on Blantyre, which is likely to remain the commercial capital. Also, the recipient Shire river is large and fast-flowing.

The main industries are those for processing agricultural products (e.g., textiles, sugar processing with an associated ethanol plant, and canning) and there are plans for a tannery and possibly a pulp-mill. For the latter, base-line studies have begun in the vicinity of a possible effluent outflow in Lake Malawi and several options for waste treatment and disposal are being considered, including the use of ponds for holding fish for both monitoring effluent quality and production of fish. Industrial development is being encouraged in Lilongwe and a five to ten year plan for the whole country is currently being prepared which will take account of relevant interests, including fisheries. New developments could include the production of cement, bauxite and more rubber, and, in the long term, even coal. Conclusion

Pollution is not a serious problem, there being treatment facilities for sewage, little industrial development, and tight control of discharges through a charging system based upon the quality and quantity of effluent in relation to the dilution available. Water legislation is nevertheless to be reviewed and there are also plans to strengthen technical expertise within the Water Department and provide laboratory facilities to improve the monitoring and control of effluent quality.

3.2 Pesticides

3.2.1 The Sudan

The National Pesticides Committee enforces the Pesticides Act 1974 which regulates all aspects of pesticide usage including import, registration and field trials (El Tigani et al., 1980). It has close links with the Agricultural Research Cooperation which has a Plant Protection Department and a Fishery Research Centre.

The situation with regard to pesticide usage and control has been reviewed by George and El Moghraby (1978) in relation to fisheries interests.

The main usage of pesticides occurs in the large tract of irrigated land in the Gesira area south of Khartoum, lying between the Blue and the While Niles. Here is produced about half the cotton on which the Sudan economy depends so much. It is normally heavily treated with repeated applications of a variety of pesticides at a total rate of about 4 kg/ha/year. The irrigation channels contain fish which suffer periodic mortalities partly from direct spraying, spray drift and washing of empty containers and clothing in the channels. The fish are exploited for subsistence fishing, even though they are not meant to be utilized in that way. Pesticide residues have been found at moderately high concentrations in the fish but no regular systematic monitoring programme has been or is known to be planned. Moderately high concentrations of residues have also been found in the adipose tissue and milk of humans in the area but no epidemiological studies have yet been carried out; the levels are comparable to those found in developed countries.

The irrigation channels have been considered for use in aquaculture (George, 1976) but further investigation of their content of pesticides is considered necessary before pursuing that possibility further.

Over recent years there has been a tendency to use the more selective and the less persistent pesticides, and the total quantity has not shown any marked increase, probably because the newer materials are more expensive than DDT. There is also a determined effort being made by the Fishery Research Centre, with the help of FAO, to develop an integrated pest control programme in which pesticides do not necessarily play the dominant role, and also to deploy task forces in the field to supervise aerial spraying operations to prevent excessive overdosing.

The control of aquatic midges, mosquitoes and snail hosts of schistosomiasis is nowadays also tackled with chemicals of relatively low toxicity to fish, although those chemicals effective against the eggs and cercaria of schistosomes are also very toxic to fish. The World Health Organization has considered this question (WHO, 1978) and advocated caution and selectivity in the use of pesticides for malaria control, and their use only as an intermediary to prevention and the permanent elimination of vector breeding; for schistosomes the World Health Organization has expressed its preference for environmental management methods, rather than the use of pesticides.

Research work has been carried out at the University of Khartoum on the acute lethal toxicity of pesticides to fish and further work is planned to study the long-term effects.

Experiments are also being carried out by the Fisheries Research Centre on the use of the Chinese carp (Ctenopharyngodon idella) for aquatic weed control in the irrigation channels and results suggest that it may also be of value in controlling populations of vector snails of schistosomes.

Elsewhere, on irrigated lands outside the Gesira area, the potential problems for fisheries from pesticide usage generally exist on a smaller scale, usually involving fewer sprays on cotton. A minor but high-rate relatively uncontrolled mode of application of pesticides occurs, however, on numerous small vegetable plots on the banks of the White Nile.

One major source of pesticides in water, although of short annual duration, has been the use of 2,4-D for the control of water hyacinth (Eichhornia crassipes) in the 1 800 km length of the White Nile from Juba to Jebel Aulia, where it has been sprayed at the rate of 4.4 kg/ha. The whole of the ecosystem has apparently been affected (El Moghraby, 1975), and mass mortalities of fish have occurred in the past (1969); the use of herbicides is considered by some to present the greatest problems for fisheries in the future, and to warrant further research. The hyacinth spraying programme is now controlled by a separate Fisheries Administration based at Juba.

Although it has been alleged (University of Zambia, 1973) that the use of chemical fertilizers has affected the quality of groundwater in the Sudan, no confirmation of this has been found.

3.2.2 Kenya

There is at present a lack of government advice (no leaflets, for example) on the safe use and disposal of pesticides, although there is a committee on pesticides, on which manufacturers are represented, and they provide an extension service which partly fulfils the need, e.g., in dealing with the safe disposal of animal dips. However, the Government has considered the subjėct and a new Pesticides Bill is before Parliament. Consideration is also to be given to the banning of certain chemicals, such as DDT, dieldrin and aldrin (Kenya, National Environment Secretariat, 1979), but the need to consider the acute toxicity to fish of alternative, less persistent, chemicals, has been pointed out by Meadows (1980).

Approximately 5 000 tons of pesticides/year are being used on a relatively small area where coffee, cotton maize and horticultural crops are grown, as well as on irrigated areas (Mbote, 1979). The usage on some crops, e.g., wheat, may be affected by the current subsidy but generally it is considered it will increase, despite rising costs.

Pesticides and their breakdown products have been found in water and aquatic organisms including fish (Kallqvist and Meadows, 1977) and there is concern that concentrations are approaching those that may have adverse effects. At present, however, there is no systematic monitoring of body burdens. Furthermore, there are virtually no data available on the possible adverse effects of aquatic herbicides used in rural areas (Meadows, 1980).

3.2.3 Burundi

There appears to be no scheme for screening pesticides for safe use. The principal use is on crops in the plain of the Rizizi river (Autrique, 1977), where it is likely to continue, and even increase, since the Government plans to continue to try to attract people to the area from the over-populated hills in the central northern region. The river drains into the northern, shallow part of Lake Tanganyika, and there is concern that the fisheries there might be adversely affected by pesticide run-off, especially since the nursery grounds of some of the species of importance occur relatively close inshore.

Samples of fish have been examined in 1971 and 1972 for their content of pesticides (e.g., Deelstra, 1977), and while the concentrations found have not given cause for alarm, no regular monitoring programme has yet been carried out to establish trends, if any, although further work, for which funds have been secured, is planned. The University of Burundi (or possibly REGIDESO) could carry out the necessary chemical analyses, given appropriate administrative action in Burundi. Fryer (1972) has drawn attention to the very long flushing time for a large body of water like Lake Tanganyika, having only a small outflow, and the implication that an accumulation of persistent chemicals to toxic concentrations could last for centuries in such circumstances prevention of pollution is made essential since cure may be virtually unavoidable. Clearly, experience of pesticides in North American lakes has some relevance.

3.2.4 Tanzania

There is no formal procedure for clearing pesticides for use in Tanzania, but the Tropical Pesticides Research Institute, established in October 1979, has the responsibility for registering pesticides, and in doing so, proposes to seek information on their properties, including toxicity to fish. It is empowered to carry out research on environmental pollution and to administer regulations dealing with the supervision, regulation, and distribution of pesticides.

The use of pesticides in agriculture is not widespread. In the central region, about 5 t/year of phenothion has been used to control quelea birds. In the Kigoma region to the west, it has been reported that 75 t/year of 5 percent DDT was used on maize, and it is speculated, following an accidental spillage during transhipment in Kigoma harbour, that this might present the greatest danger to fisheries in Lake Tanganyika, rather than agricultural run-off. In 1979, a special tsetse-control project was started in the northwest part of the country between Rwanda and Lake Victoria, in relation to a new cattle-ranching experiment, which involved five aerial sprayings of endosulphan at 6–8 g/ha at 14-d intervals; Lake Ihimpa and Lake Burigi are in the area concerned but no studies were made of the possible side effects on fish; however, the scheme has now been abandoned. In the area near Nbozi near the northern part of Lake Nyasa, very heavy applications of copper fungicides have been used on coffee the consequences of which are already causing concern because yields have been depressed by the high concentration in the soil, but no information is available on effects on drainage water and fisheries.

A programme of monitoring pesticides in fish in Lake Tanganyika and ancillary work on the toxicity of selected pesticides to indigenous species of fish are planned and will be carried out by the Fisheries Institute's Centre at Kigoma when personnel are available. Proposals to examine the effect of pesticides on growth and fecundity of indigenous fish species, that have not yet been kept successfully for long periods in captivity, are ambitious and are in abeyance.

3.2.5 Zambia

There is no legislation in Zambia relating specifically to the use of pesticides, but the Ministry of Agriculture (and Water Development) took the initiative in 1976 in setting up a committee on pesticide control to deal with legislation and safety, and the Ministry does provide some advice on safe use although extension and services to farmers are largely in the hands of commercial companies supplying the chemicals. The draft Environment Conservation Act being prepared by the Ministry of Lands and Natural Resources also contains guidelines on the prevention of pollution by pesticides and that Ministry has been approached by the Ministry of Agriculture seeking clearance on the use of pesticides.

Kaoma and Salter (1979) have considered pesticide usage in Zambia and have pointed to the Mazabuka area near the Kafue river as one of relatively high risk from water pollution because of heavy usage on maize, sugar and other crops, together with the presence of large numbers of cattle and the fact that the farms are drained by a series of parallel rivers running into the Kafue flats. Tsetse fly control aerial spraying operations, using endosulphan, have also centred nearby, e.g., near Mapanza and Macha, south of the Kafue river and near Mumbwa to the north. It was reported that application rates higher than called for in the programme were occasionally being used.

No monitoring of pesticides in fish has yet been carried out in Zambia but the Zambian Tsetse Control Office of the Ministry of Agriculture and Water Affairs will begin analysis of four commonly-found species of fish and crustaceans that are being collected by FAO personnel carrying out the Tsetse fly control programme, provided that financial support for the overseas expert is forthcoming. DDT and its metabolite have already been detected in control fish. The National Council for Scientific Research also plans a programme on pesticides in the environment, including water, fish and mud, which it intends to implement with the help of an overseas expert already in post, who will train local staff.

Wessels et al. (1980) examined the content of chlorinated hydrocarbon insecticides in the eggs of crocodile (Crocodilus niloticus) in Lake Kariba and in the Zambesi river upstream of the lake and found relatively high concentrations of BHC and DDT in the latter, which pointed to the need for intensive studies of the fate of these pesticides in view of the development of the lake fisheries; residues of DDT. but not those of BHC, were consistent with known land usage in Zimbabwe. Although recent analysis of fish of various species from Lake Kariba shows the presence of organochlorine pesticides at low levels, further samples are to be analysed wherever possible to provide further background information and perhaps assist in the demarcation of problem areas (T. Tannock, pers, comm.)

3.2.6 Malawi

The Ministry of Agriculture and Natural Resources requires pesticides to be screened and it issues advice on their safe use, e.g., in handbooks relating to crop protection (Matthews et al., 1974) and veterinary use, in which warnings are giving regarding toxicity to fish. The Ministry has recently drafted Pesticide Regulations under the Agriculture, Fertilizers, Farm Feed and Remedies Act, introducing strict registration of all pesticides used in the country, and requiring information on properties, including toxicity to fish.

Plans had been made for the Fisheries Department to carry out any necessary tests using idigenous species in ponds, but the project is now in abeyance for lack of funds. For the same reason, a project proposal for a research laboratory, designed to handle all pesticide analyses in Malawi, is also not now included in the current five-year programme.

Pesticide usage is mainly concentrated on cotton grown along the lake shore and particularly in the Shire Valley, though other treated crops include tobacco, maize and tea. Fisheries are important in the Shire Valley, producing about 12 000 out of a total of 70 000 t/year. Between 1973 and 1978 fish from the Elephant Marsh near the cotton growing areas, and also from Lake Makoka near the Agricultural Research Station, have been sampled and analyzed for DDT (Pickering et al., 1980). Concentrations of DDT and its metabolites in the fish are generally too low (average less than 0.05 mg/kg in muscle) to cause concern, although a relatively high concentration (2.7 mg/kg) in the ovaries of one individual Clarias gariepinus raises the question of whether it could be high enough to cause adverse effects on reproduction.

3.2.7 Summary and conclusions

Pesticides are being used increasingly. They have caused unwanted fish kills and have been found in the tissue of fish, sometimes at concentrations which have given cause for concern because they might be approaching values having long-term and sub-lethal adverse effects. Comparatively few tests have been carried out to measure the toxicity of pesticides to African species of fish and no long-term tests, or regular monitoring programmes for concentrations in fish, have yet been carried out, although several relevant proposals are in abeyance. This situation needs rectifying. Some, but not all, countries have a system for screening pesticides for safety and for issuing advice on safe use, including information on toxicity to fish.

3.3 Conclusions

3.3.1 General

A decade ago, water pollution in some African countries was not considered to be a serious problem in relation to inland fisheries (Thorslund, 1971). But since then, as forecast, there has been an increase in urbanization and industrialization and also in the use of pesticides for agricultural and health purposes and, as a result, the occurrence in some countries of local acute problems involving fish kills. The extent of less obvious problems is not known because no relevant studies have been carried out, either in the laboratory or field.

In general terms, the main sources of pollution are sewage, sewage effluent and discharges of other highly oxidizable wastes from the production and processing of agricultural and forestry products. notably textiles, leather coffee sugar sisal and wood pulp and paper. In addition, chromium occurs in tannery waste and copper and other inorganic chemicals are important in one or two countries. Heavy industry is virtually absent and is unlikely to develop to any great extent very quickly. The application of pesticides, which has also caused fish kills has aroused concern about possible long-term and sublethal effects on fish, including the accumulation of chemicals in edible tissues.

In the face of these developments, a number of remedial measures have been taken, and those that seem to have helped in controlling water pollution are listed below (not necessarily in order of importance).

For sewage and industrial waste discharges the measures include:

  1. use of alternatives to water-borne sanitation in small urban and rural areas;

  2. making inventories of discharges to surface water and sewers;

  3. surveying river water quality;

  4. classifying rivers in terms of water quality and designated use;

  5. integration of data on river flow with those on water quality

  6. revision of the water pollution control legislation and institutional arrangements for its enforcement;

  7. utilization of effluents for irrigation purposes, the culture of fish and the recovery or manufacture of useful by products;

  8. establishment and enforcement of standards for discharges of effluents to streams, taking account of the quality and quantity of effluent and receiving water (based on dry weather flow), downstream water use and self purification capacity of the receiving water;

  9. development of the capacity to carry out toxicity tests on effluents, using fish;

  10. control of discharges to sewers;

  11. definition of water quality objectives for specific water uses, particularly fisheries;

  12. promotion of the use of oxidation ponds for waste water treatment, including research on the subject;

  13. development of methods of treating waste waters, in collaboration with industry;

  14. specification of pollution control equipment and the provision of subsidies for its purchase and installation;

  15. development of an effluent and water quality monitoring capability;

  16. management of water quality on a river basin basis within a national context;

  17. coordination of water resource developments with those of industry, taking account of fishery and other relevant interests;

  18. creation of a small national coordinating ‘Environmental Protection Agency’, independent of existing ministries; and

  19. consideration of procedures for assessing the environmental impact of new projects;

For pesticides, remedial action has included:

  1. establishing legislation to register all pesticides used, and assess data on toxicity to fish and other aquatic organisms, and advise on safe use;

  2. carrying out of toxicity tests on indigenous species of fish;

  3. supervision of spraying operations by special teams of observers;

  4. use of insecticides of low toxicity to fish;

  5. measuring of concentrations of pesticides and their metabolites in fish and other sectors of the aquatic environment; and

  6. development of integrated pest control programmes in which pesticides do not necessarily play a dominant role. This has included the use of fish for the control of insect and gastropod hosts of human parasites.

Activities which seem to have been absent, despite their relevance, include:

  1. cost/benefit analysis, stressed as important by McAuslan (1980) when deciding whether or not to take a specific action involving environmental protection;

  2. an active ‘fish lobby’ of commercial fishery interests, considered to have potential value by Bernacsek (1980a);

  3. development of the idea of ‘fish master plans’ (Bernacsek, 1980a) for river basins, to be viewed alongside plans for the development of towns, water resource and industry (also referred to by R.A. Borthwick at the opening of the Fourth Session of CIFA); and

  4. thorough investigations either in the laboratory or the field of the relation between water quality, as affected by water pollution, and fish and fisheries under East African conditions.

These activities have proceeded to differing degrees in different countries, but enough has been done, or left undone, as the case may be, to justify a more detailed exchange of information and experience between different African countries than has been possible in this report. It is, therefore, recommended that such liaison should be formally promoted by CIFA, with a view to the development of collaborative efforts to identify priorities in more detail and fill major gaps in knowledge.

In the meantime, some of the activities listed can be picked out for brief discussion here to examine their merits and the way in which they might, with advantage, be pursued further. The detail is already given in Sections 3.1 and 3.2.

First of all, it is clear that most of these activities relate not so much to fish and fisheries (although items 9, 11, 21, 23 and 24 have an obvious direct bearing on them). but to the wider questions of water pollution control and environmental management in which fisheries are but one element, and in which a multidisciplinary approach is essential. This requires close collaboration between those primarily concerned with fisheries and those primarily concerned with, for example, water quality control, each group needing an appreciation of the role of the other.

3.3.2 Use of alternatives to water-borne sanitation

The pit latrine, soakaway and cesspit are used extensively in small urban and rural areas, and although there are moves to improve supplies of piped potable water to many of these, sometimes linked to the development of sewerage and sewage treatment, this may not necessarily lead to more water-borne sanitation and, indeed, there may be advantages in retaining traditional methods of disposal, or perhaps adapting them for the production of bio-gas. Such utilization of human waste is already common in some developing countries, but as yet is found only on a small scale in East Africa. The subject is really outside the field of direct interest to CIFA, but those involved in water pollution prevention and control should be aware of information on current technology (e.g., Rybczynski et al., 1978).

3.3.3 Inventories of discharges

An essential first step in dealing with water pollution form sewage and industrial wastes is to make an inventoy of all discharges. There may be several ways of achieving this. In Kenya, for example it was carried out for discharges to surface waters, with the help of WHO; in Burundi, it is being done by government authorities; in Tanzania it is in progress with the help of consultants, as each major urban development plan is prepared; while in the Sudan, the University proposes to undertake the task. In several countries, e.g., Kenya, Tanzania Malawi and Zambia, licensing of water abstraction is linked more or less directly to a requirement for information on the quality and quantity of effluent that may result from use of the water, but local authorities frequently have control of discharges to the public sewer.

3.3.4 Legislation

The water pollution control legislation has been evolving rapidly in several countries and is still under review in most of them. In a few cases, however, it has already reached the stage when it is being used effectively to control pollution, e.g., in Kenya and Malawi, where the licence to abstract water is closely linked to effluent quality control. In Kenya, revocation of the abstraction licence could follow a breach of the conditions under which the effluent is permitted to be discharged; in Malawi a system of charging is imposed whereby the sum levied increases as effluent volume and quality exceed certain standards. In general, legislation that enables conditions to be imposed on effluent quality and quantity is preferred to rigid definition of standards in the legislation itself, and an isolated suggestion (in Zambia) to prescribe in the legislation numerical values for environmental and effluent quality, is not generally applauded.

Since the subject is in such a fluid state, there would appear to be merit in the idea of an exchange of information and ideas between African countries so that each may benefit from the others experience. It is, therefore, recommended that the subject be considered by CIFA, and it is suggested that the simplest procedure would be to arrange for the latest legislation, as well as currently freely available draft proposals to be exchanged each with a commentary by the donor country, emphasizing the advantages and disadvantages.

3.3.5 Utilization of effluents

Again, this subject is not strictly within the terms of reference of CIFA but a knowledge of its possibilities is of general background value to those involved with pollution and fisheries, especially as some involve fish culture. The International Research Development Centre has sponsored a project in a number of countries (including Kenya) involving the production of fish in sewage fed lagoons, and in any case fish often occur in the final ponds in a series. Even if the fish are not utilized for human or animal consumption, they clearly can play an invaluable role in monitoring the quality of the final effluent. Such a use of fish in the final lagoon of a treatment system has also been envisaged as a possibility in one of the alternatives being considered for disposal of the waste from a proposed pulp mill in Malawi.

Other developments in this area include the utilization of effluents for irrigation purposes, as in the Sudan, and the conversion of sugar refinery waste into methanol as as now carried out in Malawi, for example, and as proposed in Kenya. Subjects amenable to research, as has been called for by Stout et al., (1976), include the feasibility of converting feedlot wastes into industrially useful oxychemicals, and the development of more efficient effluent control equipment in fertilizer plants.

3.3.6 Effluent and environmental standards

In establishing effluent standards, there is a general preference expressed for those that are tailored to individual cases rather than having blanket coverage by uniform values of particular water quality characteristics, irrespective of local circumstances. Nevertheless, guidelines are often regarded as a necessity and are available in several countries, in provisional form for example in Tanzania and Malawi, and are being developed elsewhere; suggestions to embody these rigidly in the legislation are generally resisted.

There is general agreement that, in prescribing effluent standards account should be taken of the quality and quantity of the effluent and the receiving water, downstream water usage, and the self purification capacity of the latter; the extent to which this is achieved, however, varies in different countries. A basic requirement is the availability of data on river flow, especially under dry-weather flow conditions, which implies the need for close coordination between hydrologists and those involved in water quality control. For seasonal streams, off-river storage has been envisaged for some effluents in Kenya. In Malawi, the volume of effluent is also considered separately from its dilution, so as to encourage recirculation of process water.

Although fisheries may be regarded as a legitimate downstream water use, which should be taken into consideration in any classification system of rivers, the usage actually considered in formulating effluent standards is most often potable water supply per se, as in Kenya, or potable supply explicitly linked to fisheries and discharge to lakes, (this being the most demanding for water quality), as in Malawi. The problem is partly that water quality criteria for African fish have not yet been developed, through either experimental work on native fish species under controlled conditions in the laboratory (except some preliminary work on their dissolved oxygen requirements and survival at acutely lethal concentrations of some pesticides), or field observations of fish and fisheries in relation to water quality and pollution, or the critical review of relevant data available for related species. In Kenya, data for trout are presently taken as a guide, but a need has been expressed for more work in this field, analogous to that carried out for European freshwater fish by the European Inland Fisheries Advisory Commission (EIFAC), as updated and summarized by Alabaster and Lloyd (1980). It is therefore recommended that CIFA should take the initiative in carrying out critical reviews of the literature on water quality criteria for African freshwater fish and should also consider research needs. The subjects of considerable interest to East Africa include the dissolved oxygen (DO) requirements of fish and the effects of chromium (in tannery wastes) copper and effluent from pulp and paper manufacture. Of these, DO and copper have already been covered by EIFAC, although much literature has accrued, especially on the latter, since the report was updated in 1979; chromium is included in EIFACs current programme. It is therefore further recommended that close liaison be established between CIFA and EIFAC Working Party on Water Quality Criteria for European Freshwater Fish.

The self-purification capacity of streams is seen as an important factor to be taken into account in determining conditions of consent for effluent discharges, especially in relation to changes in dissolved oxygen concentration caused by sewage effluent and other highly oxidizable wastes. However, the extent to which it can be taken explicitly into account is severely limited, because it is poorly understood in African rivers. The consultant is aware of only one research project on the subject in the countries visited in Africa (in Kenya); also a simulation model has been applied to oxygen balance in one river (in Tanzania), though in this case there was no proof available of its applicability (to the effect of a proposed discharge of effluent from a paper mill on the Rufiji river). Clearly, there is a need to evaluate the results of relevant research in Africa and elsewhere, with a view to preparing a manual to provide guidelines on how best to predict the oxygen balance of streams under African conditions, and thus set realistic standards for BOD and other water quality characteristics of effluents containing oxidizable mater. It is therefore recommended that CIFA should take steps to fulfil this need and also consider research needs in this area.

3.3.7 Toxicity testing

The capacity to carry out toxicity tests using indigenous fish is seen as having value for investigations carried out to identify sources of toxic wastes not otherwise easily identified and measured, for monitoring the quality of such sources, for screening pesticides for acute toxicity, and it is also regarded as an ultimate necessity in establishing water quality criteria. Investigations of effluents have been carried out occasionally (e.g., by Kenya) or are planned for this purpose (e.g., for discharges to Lake Victoria in Tanzania) and for monitoring the proposed discharge of pulp-mill effluent (e.g., in Tanzania and Malawi); in Tanzania there is interest in using a standard toxicity test for effluents for which liaison with the International Standards Organization is desirable, since draft standard methods are in an advanced stage of preparation. Short-term toxicity tests on pesticides have already been carried out to some extent (e.g., in the Sudan), or have been planned (e.g., in Tanzania and Malawi) and have particular value, in view of the likely increase in use in the future, including the introduction of more herbicides, and the fact that more-than-additive effects of mixtures of pesticides are more commonly found with this class of compound than with the more commonly-occurring sewage and industrial waste contaminants such as ammonia and heavy metals (EIFAC, 1980). It is recommended that CIFA should liaise with EIFAC in keeping developments in Africa in this field under review.

3.3.8 Waste treatment processes

In general, there is a dearth of expertise within government on waste-water treatment technology but there is, at the same time, a recognition of its value for advising industry on the means by which it may attain the standards of effluent quality demanded of it. In Kenya, for example, where appropriate, expertise has been available; collaboration between government and industry has resulted in improved methods of dealing with wastes from the processing of coffee. Since these wastes also occur in other African countries, there is a need to disseminate the results of this and any other relevant work more widely and to produce a manual for general guidance.

There is also a need to consider methods of treating other wastes that may be of particular importance to Africa, such as those from the processing of sisal and wood-pulp and paper, and, if possible, to advise on the most appropriate treatment technology to be adopted. Furthermore, special attention should be given to lagoons which, in Africa, are particularly suited to, and much used for, the treatment of sewage and other wastes because of the general availability of cheap land, high ambient temperature and solar radiation, as well as ease of operation. However, performance is not necessarily optimal and there is a need to examine its relation to design characteristics so that appropriate advice, based on experience, can be promulgated.

It is therefore recommended that CIFA should become involved in the dissemination of information and advice on waste treatment processes, to which end it should consider the production of the following:

  1. an annotated list of published papers on waste treatment processes relevant to Africa (e.g., for sewage and wastes from the processing of sugar, coffee, canneries);

  2. a critical review of the literature on the use of lagoons for waste water treatment in Africa and the preparation of a manual giving advice on design and operation;

  3. a manual on the treatment of wastes from the processing of wastes from coffee; and

  4. a manual on the treatment and monitoring of pulp and paper mill effluents in Africa.

3.3.9 Water quality management in relation to fisheries

The concept of river basin management of water resources, within a national context, well developed in countries such as the U.K., is found in operation to a limited extent within some African countries. In Kenya, for example, there are several River Basin Development Authorities, though not complete national coverage, and in Tanzania a notable example is that for the Rufiji river basin. Their value for the protection of fisheries depends on the effectiveness with which they take account of, and resolve, the conflicting demands on water resources. What has detracted from their effectiveness in this regard has been failure to consult sufficiently between different interests, such as those involved with the development of industry, hydro-electric power, urban areas, forestry, agriculture and fisheries, although it is evident that more attention is now being given to the need for such coordination.

At the national level there is growing interest in the formation of ‘Environmental Protection Agencies’ independent of existing ministries, good examples being that already existing in Kenya and that proposed for Tanzania (McAuslan, 1980). There is also considerable interest in the development of procedures for the assessment of the impact of development on the environment. It is recommended that CIFA should consider how the needs of fisheries should be taken into account in the preparation of Environment Impact Statements.

At the international level there has been collaboration between different countries on the development of water resources, e.g., of the Nile and of the Kagera river basin, and on the development of fisheries, e.g., in Lake Tanganyika, but no similar initiatives are being taken at present relating to the possible impact of water pollution on fisheries. It would seem, however, to be a subject of considerable importance for the future because of the large number of rivers and lakes in Africa that actually demarcate national frontiers. At present there is no evidence that there are serious pollution problems affecting fisheries in these waters, although no detailed studies have yet been carried out to investigate the point. Nevertheless, there is anxiety already being expressed about the possibility of future problems, for example in relation to inshore waters in Lake Victoria and Lake Tanganyika. It would therefore seem prudent to obtain agreement now among African countries to protect these international waters from the possibility of damage to fisheries from water pollution in the future. Indeed, it has already been suggested (Ssentongo, 1979) that there should be bilateral or regional mechanisms for pollution abatement in relation to the needs of fisheries. The subject has been discussed for the marine environment by Portmann (1978) who, after pointing out the disadvantages of the rigid protocols that have already been promulgated, advocates a simple international agreement or declaration with built in flexibility, allowing for national follow-up administrative action as required.

It is therefore recommended that CIFA should promote the establishment of a Convention on Pollution Control for African Waters whereby member countries agree to control their discharges of wastes to international rivers and lakes so as to protect the fishery resources therein from water pollution.

3.3.10 Pesticides in fish

For persistent chemicals reaching the environment the principle of their control, by identifying the critical target organisms, whether it be man or fish or other organisms, setting appropriate environmental quality objectives and establishing appropriate monitoring have been well described for the marine environment by Portmann (1978) and apply equally to freshwater.

In East Africa no regular monitoring programmes for pesticides in fish have yet been carried out, although a five-year study has just been completed in Malawi and several isolated investigations have been made elsewhere, some of which justify concern about the possible adverse effects on fisheries. Further isolated studies are in the planning stage but the appropriate technical and financial support is not necessarily assured. There is a need to review existing data on concentrations of pesticides in fish, to establish regular monitoring programmes linked to spraying operations, and to formulate and review guidance on the safe use of pesticides in relation to the needs of fisheries. It is therefore recommended that CIFA should take the initiative in promoting and coordinating activities in this field in Africa.


Although there is recognition in Africa of the need for environmental education at all levels of society (Kenya, National Environment Secretariat, 1979; McAuslan, 1980), despite the basic constraints of poverty illiteracy and scarcity of resources, and for this to be achieved using a range of methods throughout life from school to university, there is a shortage of trained manpower at all levels, and a tendency in some sectors of society to neglect the long term environmental consequences of taking short-term gains from development schemes.

The normal educational courses are generally not specialized enough to satisfy the training requirements of those involved in work on pollution and fisheries, although the training available in chemistry, mathematics and biology would be expected to provide a good technical foundation. Post-graduate courses are provided for the upper echelon in some countries. In the Sudan, for example, an Institute of Environmental Studies has been established which includes among its subject areas for research and training “freshwater ecosystem management”, with particular reference to the Jonglei Canal project and effects on fisheries. And in Kenya there are post-graduate courses available in several relevant subjects, including environmental engineering, environmental analytical chemistry, aquatic pollution biology, limnology, and environmental law. But in some cases, e.g., Zambia, the lack of job opportunities makes it difficult to enrol sufficient candidates to make the courses viable, although the University would be in a position to cover environmental sciences and ecology.

Specialist courses taken overseas apparently tend to lead the recipient to being promoted into management, rather than being allowed to practice the newly-acquired skills, and the same appears to be true for short-term specialized courses taken in Africa. Nevertheless, the courses seem to be much appreciated; for example, the few former participants to the Sixth FAO/SIDA training course held in 1978, who were contacted by the consultant and were still in post, expressed their satisfaction with it, although in some cases the facilities subsequently available in the home country were too limited to allow the new knowledge and insight gained to be applied effectively in their work. Perhaps a partial solution to these problems in future would be to link the acquisition of new expertise with the acquisition of adequate equipment and facilities to enable it to be utilized more fully. There is also a need to investigate the post-training careers of these students and examine more explicitly the use to which their training has been put.

In some countries, overseas experts have been seconded to national laboratories for a year or two to provide specialist training to local staff, e.g., for pesticide analysis in Tanzania. In others, such people have been put in overall charge of more general training at a lower level for a relatively large number of trainees, e.g., in Kenya, for a decentralized training programme for those employed in rural water supplies, which made use of the existing educational infrastructure with the addition of extra buildings provided by the sponsors.

Much of the training necessary for staff who support the senior scientists is largely within the capacity of the countries themselves. In Kenya, for example, there is a system of secondment of water inspectors from headquarters to local authorities to supervise the running of water treatment plants; such a scheme could be extended to cover other activities such as waste-water treatment, effluent sampling, chemical analysis and toxicity testing given a core of relevant expertise within the organizations concerned, or help in this respect from outside.

The importance of a multidisciplinary approach to the problems of fisheries and pollution has already been stressed in Section 3.3 and this is readily accepted in Africa. In many countries there are existing infrastructures, e.g., on fisheries, water supply and pesticide spraying to which could be grafted other relevant disciplines. In some countries the fisheries infrastructure would be involved in advising on environmental and effluent standards for fish and would benefit from appropriate advice and training including testing for toxicity; the administration in Zambia, for example, is particularly interested and that in the Sudan (which already runs a training course for its fishery technicians) would also welcome training in water pollution. The water supply infrastructure together with that on sewage treatment, which are involved in pollution control and the setting of effluent standards for discharges to sewers and surface waters, generally welcomed the suggestion to improve their understanding of waste-water treatment processes and self purification processes in rivers. Those in charge of pesticide spraying programmes were often acutely aware of the danger to fisheries and the need to avoid unnecessary damage and check for residues in fish and other organisms, but when monitoring for pesticides cannot be included as part of the programme, there may be a need to train those more directly concerned with fisheries and pollution in pesticide analysis.

It is therefore recommended that CIFA should encourage further training in these fields at all levels, by fostering an exchange of information and experience between African experts and seeking additional help from outside.


5.1 General

  1. Freshwater fisheries are vital to Africa's food supply and should be protected from damage by wastes arising from the ever-increasing urbanization, industrialization and development of agricultural and forestry products; these have already resulted in increased contamination and, in some cases, pollution of surface water.

  2. Legislation and the administrative machinery for the prevention and control of pollution are developing rapidly, and an exchange of information and experience to date in Africa in this field would be beneficial.

  3. Since water resource and other developments can damage fisheries, consultative mechanisms should be developed for future schemes to ensure that their likely adverse impact on fisheries is properly assessed and the actual impact minimized.

  4. The increased use of pesticides and their accumulation in fish, give grounds for concern that fisheries may be damaged to an extent greater than that apparent from the incidence of known fish kills. Regular monitoring programmes need to be set up and the results appraised.

5.2 Role of CIFA

In view of the above general conclusions and recommendations, which are based on the conclusions summarized and discussed briefly in Section 3.3, and the more detailed information given in Sections 3.1 and 3.2, the following specific recommendations are set out for CIFA to consider.

  1. That the CIFA Secretariat should establish a Working Group on Water Pollution and Fisheries to develop an active technical cooperative programme of work in this area, after first determining a list of priorities. Items that might be included in such a list are as follows (not necessarily in order of priority):

    1. exchange of information on the legislation and administration relevant to the protection of fisheries from water pollution;

    2. dissemination of information on waste-water treatment processes including:

      1. an annotated list of published papers on waste-water treatment processes relevant to Africa (e.g., especially sewage and wastes from processing coffee and sisal);
      2. a critical review of the literature, and preparation of a manual, on the use of lagoons for waste-water treatment in Africa;
      3. a manual on the treatment of wastes from the processing of coffee; and
      4. a manual on the treatment of pulp-and paper-mill effluents in Africa.

    3. a manual on self-purification processes in African rivers;

    4. a critical review of the literature on water quality criteria for African freshwater fish and identifying research needs;

    5. support for regular programmes of monitoring pesticides in fish and appraisal of the results; and

    6. promotion of training programmes at all levels.

  2. That the CIFA Secretariat should establish a Working Group to prepare guidelines on the assessment of the impact of resource developments on fisheries.

  3. That the CIFA Secretariat should promote establishment of a Convention on Pollution Control for African Waters whereby member countries agree to control their discharges of wastes to international rivers and lakes so as to protect the fishery resources therein from water pollution.

These recommendations were considered and endorsed by the CIFA Seminar on River Basin Management and Development, and the Fourth Session of CIFA held in Malawi on 8–12 December 1980.


On behalf of the FAO Committee on Inland Fisheries of Africa (CIFA), visits were made between 22 September and 29 October 1980 to Burundi, Kenya, Malawi, the Sudan, Tanzania and Zambia to examine the nature and extent of water pollution problems affecting freshwater fisheries, the measures being taken to deal with the situation and the need for further action.

The consultant was impressed by the degree to which the authorities, aware of the importance of fisheries, are improving their legislation and technical expertise to protect them from water pollution. Problems seem to be localized at present but there is a dearth of quantitative information on their extent and significance. It was evident that both the legal instruments to protect water quality and the expertise available to back them up varied widely in scope and effectiveness among the countries visited. Some are quite advanced in dealing with specific kinds of problems, such as those from the discharge of coffee wastes, whereas others lacked the resources necessary to implement legislative controls. It was generally agreed that lack of specific technical information and of monitoring facilities and research equipment are major constraints to effective action.

There is a need to organize an exchange of information and experience between all African countries, culminating in some cases in the preparation of critical reviews, guidelines, manuals and protocols relevant to pollution control. There is also a need for advice and training from developed countries working in collaboration with Africans.

General and specific recommendations are made for CIFA to endorse these conclusions, and to form working groups to foster further developments. The most important of these are:

  1. dissemination of information on pollution control legislation and waste treatment technology relevant to Africa;

  2. studies of self-purification processes in rivers and of the environmental requirements of African species of fish.


African Business, 1980 Article in March issue. No.19:43

Alabaster, J.S. and R. Lloyd, 1980 Water quality criteria for freshwater fish. London, Butterworths for FAO, 297 p.

Alkbrant, F., 1979 Rural water quality programme in Tanzania. Final report. Ministry of Water Development, Energy and Minerals. Stockholm, Swedish International Development Authority, 328 p. (10 annexes)

Arunga, J.E., E. Okemwa and J.O. Nyaoke, 1978 Status of aquatic pollution and its control in Kenya. Paper prepared for Sixth FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources. Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, FIR:TPLR/78/Inf.13:7 p.

Autrique, A., 1977 La lutte contre les depredateurs du cotonnier au Burundi. Departement Defense de Vegetaux. Bujumbura, Institut des Sciences Agronomiques du Burundi (ISABO), 9 p.

Baker, D. and B.S. Meadows, 1978 Water development and resource management. GOK/UNEP/UNDP Project on Environment and Development, (SS00108):200 p.

Bernacsek, G.M., 1980 Preliminary assessment of the possible effects of the Mufindi pulp mill on fish yields of the Rufiji Basin, Tanzania. Report submitted to the Fisheries Division of the Ministry of Natural Resources and Tourism, and the Rufiji Basin Development Authority. Dar es-Salaam, Department of Zoology, University of Dar es-Salaam, September 1980:10 p. (mimeo)

Bernacsek, G.M., 1980a Freshwater fisheries and industry in the Rufiji river basin, Tanzania: the prospects for existence. Paper presented to the FAO Seminar in River Basin Management and Development, Malawi, 8–12 December 1980. Dar es-Salaam, University of Dar es-Salaam, Department of Zoology, 9 p (Draft MS).

Burundi, 1978 Plan quinquennal de developpement economique et social du Burundi, 1978–82

Chapman, D.W. et al., 1971 Ecology of fishes in the Kafue river. Central Fisheries Research Institute, Chilanga, Zambia. Moscow, Idaho, University of Idaho, Technical Report 2, FI:SF/ZAM 11:66/7

Charman, J.A., 1978 Water quality standards for the control of mining industry discharge. Nchang Consolidated Copper Mines Ltd., Roan Consolidated Mines Ltd., Mining Industry Technical Service, Kitwe, 17 July 1978, 1 p.

Chidumayo, E.N., 1979 Environment and development in Zambia: an overview. In Proceeding of the National Seminar on Environment and Development. Lusaka, edited by D.S. Johnson and W. Rode. Occas.Stud.Zambian Geogr.Assoc., (10):9–24

Curry-Lindahl, K., 1971 Biological effects of pesticides. In Pollution and environment in Zambia. Seminar report, 16–17 March 1973. Lusaka, University of Zambia, pp 102–13

Daily News, 1980 Tanzania, Article in issue of 14 October: 1 p

Deelstra, H., 1977 Danger de pollution dans le Lac Tanganyika (Bassin de Bujumbura). Bull.Soc.Belge Etud. Geogr., 46(1):23–35

EIFAC, 190 Working Party on water quality criteria for European freshwater fish. Report on combined effects on freshwater fish and other aquatic life of mixtures of toxicants in water. EIFAC Tech.Pap., (37):49 p.

El Moghraby, A.E., 1975 Some effects of Eichhornia crassipes (Mart) Solms on the productivity of the White Nile. In Aquatic weeds in the Sudan, with special reference to water hyacinth. Khartoum, National Council for Research, pp. 133–50

El Tigani, M. et al., 1980 Recommended insecticides, herbicides, fungicides and regulations for testing them in the Sudan. Khartoum, Agricultural Research Corporation, Ministry of Agriculture, Food and Natural Resources, 26 p.

FAO, 1979 Yearbook of fishery statistics. Annuaire statistique des peches. Anuario estadistico de pesca. Catches and landings. Captures et quantites debarquees. Capturas y desembarques. Yearb.Fish.Stat./Ann.Stat.Peches/Anu.Estad.Pesca, (46):371 p

FAO, 1980 FAO regional conference for Africa. Paper presented at the Eleventh FAO Regional Conference for Africa, Lome, Togo, 16–27 June 1980. Rome, FAO, ARC/80/INF/4:7 p.

Fryer, G., 1972 Conservation of the Great Lakes of East Africa: a lesson and a warning. Biol.Conserv., 4(4):256–62

George, T.T., 1975 Water pollution in relation to aquaculture in Sudan. CIFA Tech.Pap., (4) Suppl.1:753–63

George, T.T. and A.I. El Moghraby, 1978 Status of aquatic pollution in the Sudan, its control and protection of the living resources. Paper prepared for Sixth FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources, Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, FIR:TPLR/78/Inf.20:21 p.

Hopson, A.J., 1979 Summary report on the evaluation of the probable impact of the Stiegler's Gorge Dam upon the fish and marine fisheries of the Rufiji river and its Delta. Project Technical Paper No.3, FAO/TCP/URT 8806 (1):9 p.

Kallquist, T. and B.S. Meadows, 1977 Pesticide levels in the Kenyan rural environment. Afr.Environ., 1977 (2 and 3)1:163–70

Kaoma, C. and L.F. Salter, 1979 Environmental pollution in Zambia. In Proceedings of the National Seminar on Environment and Development, Lusaka, edited by D.S. Johnson and W. Roder. Occas.Stud.Zambia Geogr.Assoc., (10):181–216

Kenya, National Environment Secretariat, 1979 1979–83 Development plan, Chapter II. Policy Framework, Section 2.5 Environmental Policies. National Environment Secretariat, Kenya, 36 p.

Kratel, R., 1979 Proposal for a Water Pollution Control Act within the Republic of Zambia, Africa, and Appendix (1), Requirement for discharge of used water (water and sewage) into the receiving water or into the public sewer. Vienna, UNIDO, 47 p., + Appendix (2), Water quality criteria for Zambian waters, 19 p. + tables

Magasa, J.H., 1978 Possible sources of aquatic pollution and their control in Malawi. Paper prepared for the Sixth FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources, Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, FIR:TPLR/78/Inf.25:2 p.

Matthews, G.A. et al., 1974 Malawi crop production handbook. Lilongwe, Extension Aids Branch, Ministry of Agriculture and Natural Resources, 87 p.

Mbote, W.N., 1979 Planning for national development. In FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources. Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, Swedish Funds-in-Trust, TF-RAF 112 (Swe)-Suppl.1:199–209

McAuslan, J.P.W.B., 1980 Report on a National Environmental Protection Agency for Tanzania. Nairobi, UNEP, March 1980, 80 p.

Meadows, B.S., 1980 The quality of water in Lake Victoria Basin and its protection. Seminar Ser. Lake Victoria Basin Dev., Inst.Dev.Stud.Univ.Nairobi, (7)Rev.1:16 p.

Moore, G. and L. Christy, 1978 Legislation for control of aquatic pollution, Part I. International aspects. Part II. National aspects. Paper prepared for the Sixth FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources. Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, Swedish Funds-in-Trust, FIR:TPLR/78/6, FIR:TPLR/78/7:10 p.

Msuya, C.D., 1980 Speech by the Hon. C.D. Msuya, M.P., Minister for Industries, to the budget session of the National Assembly for the 1980/81 period. Dar es-Salaam, The Government Printer, 58 p.

Muller, M., 1978 Will the Jonglei be Sudan's lifeline? New Sci., 78(1099):140–43

Mumba, A.C., J.A. Chanda and A.S. Muleya, 1978 Aquaculture and pollution control in Zambia. Paper prepared for the Sixth FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources. Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, FIR:TPLR/78/Inf.24:15 p.

Muncy, R.J., 1973 A survey of the major fisheries of the Republic of Zambia. A report prepared for the Central Fisheries Research Institute, Chilanga project. Rome FAO, FI:DP 9/10 ZAM/511/3:69 p.

Mwamanga, E.T., 1980 East African report on trade and industry. (Interview with Minister of Industry) reported in Afr.Bus., Kenya, May issue: pp 12–3

Ngoile, M.A.K., A.E. Challe and R.R. Mapunda, 1978 Aquatic pollution in Tanzania. Paper prepared for the Sixth FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources. Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, FIR:TPLR/78/Inf.19:9 p.

Ngunya, E.A., 1975 Some administrative aspects of establishing a pollution control organization in a developing country. Progress Nat.Technol., 7(2):83–91

Pickering, G.B., J.R. Cox and L. Donegan, 1980 DDT levels in the environment following cotton spraying in the Shire Valley, Malawi, 1973–78. London, Tropical Products Institute, Overseas Development Administration, 87 p.

Portmann, J.E., 1978 The Gulf of Guinea: pollution, the need for control and possible mechanism thereof. Preparatory work for the protection of the marine environment in the Gulf of Guinea and adjacent coastal areas. FAO/UNEP Joint Project No. FP/0503-77-02:53 p.

REGIDESO, 1980 Apercu sur le secteur eau au Burundi. Presente par la REGIDESO a l'attention de la KFW. Regie de Distribution d'Eau et d'Electricite, Bujumbura, REGIDESO, 29 p.

Rybczynski, W., C. Polprasert and M. McGarry, 1978 Low-cost technology options for sanitation. A state of the art: review and annotated bibliography. Ottawa, International Development Research Centre, IDRC 102e:184 p.

Ssentongo, G.W., 1979 Freshwater fisheries of Africa. FAO/SIDA workshop on Aquatic Pollution in relation to Protection of Living Resources. Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, Swedish Funds-in-Trust, TF-RAF 112 (SWE)-Suppl.131–8

Stout, B.A. et al. 1976 Energy for world agriculture. FAO Agric.Ser., (7):286 p.

Tanzania, 1980 Ministry of Finance and Planning, 1978 population census - preliminary report. Dar es-Salaam, United Republic of Tanzania, 182 p.

Tanzania, 1977 Ministry of Health, Report of the Effluent Standards Committee. Dar es-Salaam, Central Government Chemical Laboratory. Ministry of Health, CLI/77:36 p.

Thomas, S.J., D.S. Moulder and A. Varley, 1978 Bibliography on aquatic pollution in Africa. Paper prepared for the Sixth FAO/SIDA Workshop on Aquatic Pollution in relation to Protection of Living Resources. Nairobi and Mombasa, Kenya, 12 June–22 July 1978. Rome, FAO, FIR:TPLR/78/Inf.9:55 p.

Thorslund, A.E., 1971 Report on survey of inland water pollution in Uganda, Kenya, Zambia and Tanzania. Rome, FAO, FAO Regular Programme Report (11):16 p.

University of Zambia, 1973 Pollution and environment in Zambia. Seminar report, 16–17 March, 1973. Lusaka, University of Zambia, 113 p.

Welcomme, R.L., 1979 The inland fisheries of Africa. CIFA Occas.Pap., (7):69 p.

Wessels, C.L. et al., 1980 Chlorinated hydrocarbon insecticide residues in Crocodilus niloticus Laurentius eggs from Lake Kariba. Trans.Zimbabwe Soc.Assoc., 60(3):11–7

WHO, 1978 Report on the Seminar on the prevention and control of vector-borne disease in water resource development planning. Alexandria and Egypt, 21–27 March 1978, and The Sudan, 28 March–6 April 1978. WHO, Eastern Mediterranean Region Office, VBC/EM/78.1

Williams, C., 1977 Economic appraisal of the fishing industry in Zambia, June 1977. Lusaka, Department of Fisheries, 73 p.

Zambia, 1978 Ministry of Water and Natural Resources, Draft of a new water act for Zambia. Lusaka, Department of Water Affairs, Ref.HYLO 6/5/38 as proposed 6/6/78

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