UNDP/WHO Public and Environmental Health Planning Phase II UNDP/79/001 WHO/ETH/BSM/001 WATER RESOURCES DEVELOPMENT AUTHORITY ETHIOPIA MASTER DRAINAGE PLAN FOR AMIBARA & MELKA SADI AREAS HEALTH & ENVIRONMENTAL IMPLICATIONS (An Inter-Institutional Collaborative Effort) FINAL REPORT Addis Ababa February 1985UNDP/WHO Public and Environmental Health Planning Phase II UNDP/79/001 WHO/ETH/BSM/OQ1 WATER RESOURCES DEVELOPMENT AUTHORITY ETHIOPIA MASTER DRAINAGE PLAN FOR AMIBARA & MELKA SADI AREAS HEALTH & ENVIRONMENTAL IMPLICATIONS (An Inter-Institutional Collaborative Effort) Addis Ababa February 1985MASTER DRAINAGE PLAN FOR MELKA SADI AND AM IB ARA AREAS ANNEX J - HEALTH AND ENVIRONMENTAL IMPLICATIONS CONTENTS 1. INTRODUCTION Page No 1 2. PRESENT STATUS AND POSSIBLE IMPLICATIONS OF PROJECT IMPLEMENTATION 2 2.1 Water Borne Diseases 2.1.1 Schistosomiasis 2.1.2 Malaria 2.2 Water Quality 2.2.1 Chemical 2.2.2 Pesticide Levels 2.2.3 Eutrophication 3. RECOMMENDATIONS 3.1 Water Borne Diseases 3.2 Water Quality 4. MONITORING ACTIVITIES AND PROCEDURES 4.1 Water Borne Diseases 4.1.1 Schistosomiasis 4.1.2 Malaria 4.2 Water Quality Control 4.2.1 Areas of Concern 4.2.2 Recommended Monitoring 4.3 Institutional Arrangement 4.4 Costs 2 2 3 8 8 8 9 9 10 11 H H 13 I4 I5 16 18REFERENCES TABLES 1. Malaria Control Programme - Observations 2. Distribution of Malaria Parasites by Species & Locality 3. Pesticide Usage in the Middle Awash Agricultural Enterprise Area for 1983/84 crop year (five farms) 4. WHO Standard of Potable Water (1979) 5. Conductivity, pH and Dissolved Oxygen in Selected Irrigation Canals and Drainage Canals in the AIP area 6. AIP Pilot Drainage Scheme - Drainage Discharge Field Record 7. List of Pesticides used in Tibila, Awara Melka, Mille, Dubti and Dit Bahr State Farms of the Awash Valley - January 1984 8. Algal Forms Identified in Water Samples Collected in AIP on November 10, 1984 9. Capital and Recurrent Expenditure for Health and Environmental Monitoring, Amibara and Melka Sadi Master Drainage Scheme FIGURES 1. Water Sampling Points APPENDICES A Terms of Reference B List of Participants1. INTRODUCTION One of the components of the Master Drainage Plan for the Melka-Sadi Amibara area, which is intended to arrest the rising groundwater Cable and reclaim the salt affected soils, is a health and environmental impact study. In order to undertake this study, the Water Resources Development Authority requested the assistance of the Inter-Institutional Committee (see Appendix B) in a letter dated 12 October 1984 with accompanying terms of reference (see Appendix a). The terms of reference as provided by the consultants, require Che study to assess the existing health and environmental situation and develop a monitoring system in relation to water borne diseases and water quality. The study dealing with the assessment of existing situation is intended to identify actual and potential health and environmental problems which are likely to be aggravated and/or introduced by project implementation with a view co developing in-built preventive measures at the planning and design stages. The committee reviewed all available data and undertook a field survey in November 1984 to study the ecology of the area and assess the situation with regard to disease vectors and water quality. Arising from the above pre-project study, a monitoring system has been developed with the aim of assessing changes in water quality and prevalence of malaria and schistosomiasis on a continued basis with a view to undertaking timely corrective measures upon detection of any adverse effect. This report presents the findings of the pre-project health and enviromental impact study which identified the specific risks the project may create and also makes recommendations on appropriate measures for timely incorporation in the project design and operation. It also contains the monitoring systan which among other things include the type and nature of activities and the cost implications. 12. PRESENT STATUS AND POSSIBLE IMPLICATIONS OF PROJECT IMPLEMENTATION 2.1 Water-Borne Diseases The present epidemiological situation in the Middle Awash is characterised by modification of diseases endemic to the area and introduction of new diseases associated with the development of irrigated agriculture. Water related and vector borne diseases are wide spread in the area. Among these diseases, schistosomiasis and malaria are of major public health concern. 2.1.1 Schistosomiasis Schistosomiasis due to Schistosoma haematobium is endemic in the middle and lower Awash Valley mainly among the nomadic Afar populations. The area from Angelele to Gewani is highly infected due to the presence of many natural and man made swamps where Bulinus abyssinicus, the snail intermediate host, breeds and schistosoma transmission takes place. Following the installation of irrigation schemes in the upper middle Awash Valley (Amibara Irrigation Project), the swamps in the Angelele area have dried up as a result of the construction of dykes which stopped the overflow of Awash River to the flood plains. It appears as if urinary biliharziasis would gradually decrease with the destruction of the snail habitats. In fact, a survey carried out in 1981-82 showed an infection rate of 19.8Z in 7 villages considered to be endemic for the disease within the Angelele-Kortume area (Ref 1) as compared to the infection rates of 58.3Z in Angelele and 67.9Z in Kortume in 1969 (Ref 2,3). Whereas some environmental modification such as the construction of the dyke and good land levelling proved to be beneficial in reducing schistosomiasis transmission, other favourable conditions have been created by the irrigation scheme for the propogation of the disease. As a result of improper drainage and release of excess irrigation water, an extensive swamp between Asoba 2 and Dahitele was created and snail host re-established until the construction of a drain network within the Amibara Irrigation Project in 1982. Other sices of actual or potential danger are the Kortume flood plain, the pump site near Dahitele and the pool of water adjacent to Tl-3 canal. 2kiiinus abysslelIcus has been found repeatedly in the Kortume swamp which is formed as a result of diversion of flood water from the Awash Stiver and also in rhe swamps near the pusp site in Dahitele created by seepage and overflow from rhe irrigation canal. The shallow pool aear tertiary canal Tl-3 is about 50 m x LOO a resulting froa inproper drainage. 3ulinus snails were found in the pool grad the place should be considered co be dangerous. prolific growth of aquatic vegetations was seen in almost all the irrigation and drainage canals. wear is more, these canals especially chose close co human habitats are used for drinking, washing, bathing and livestock watering. It was also observed chat sone of these canals serve as disposal sites for human excreta- These activities as well as the presence of abundant aquatic vegetations in the canals are creating nicrohabitats suited for snail propagation and infection. Ln fact a major concern in the ALP area is the possible escablishaenc of snail hosts in the irrigation canals which has not place sc far. This may be due to the peculiar habitat requirements of 3uiims abyssinicus, but it is worth noting that in Somalia the species has successfully coLonized the irrigation canals (4). If this happens in the Al?, the control of urinary biliharziasis could become more complicated and prohibitively expensive. As for intestinal schistosomiasis caused by Schistosoma mansoni, the <«tnn has not yet been substantiated although Biomphalaria pfeifferi, the snail host for this parasite, is found in Melka Sadi, Amibara and Am bash. This is most likely due co the high temperature of the area which is not suitable for growth and breeding of this species. The prevalence of infection is 3.3Z and is predominantly found among the migrant workers from the highlands. With the application of scue preventive measures such as regular monitoring of the snail population, treatment of infected individuals and good water management, it is possible co prevent the escablishmenc of this parasite in the area. The planned drainage system, in as much as it avoids the formation of any stagnant water, is in principle compatible with prevention and control of water related vector borne diseases. Lack of drainage results in stagnant pools, wet areas and seepage which are often favourable for snails to breed. The extension of the flood dyke is also seen as a positive undertaking in the control of 3snails and mosquitoes. On the other hand, the open drain ditches and the auxiliary structures could in themselves create conditions favourable for the breeding of disease vectors unless properly designed, maintained and operated. Major factors that need closer attention in the existing and proposed drainage network are the intermittent discharges, siting of the drainage canals in relation to residential areas, velocity, the option of discharging the flows directly into the Kortume swamp and operation and maintenance. The performance of the main drain extension in the AIP II during the past year has been satisfactory. According to the information obtained during the field survey, the period when overflows dicharged into the Amibara extension area was only about 10 days for this year (1984) and no snail colonies were re-established. The accumulation of water for a period not exceeding two months does not appear to create a habitat suitable for the snail hose, but even one week is considered to be dangerous in the case of malaria transmission. The recommended velocity in the open drains during normal flow is 0.3 m/s. Taking inco consideration the nature of the canal bed, the volume of discharge especially from the rejection flows and the abundance of aquatic vegetation noted often in the canals, this velocity does not appear to be high enough to immobilise and dislodge snails. Halidebi is a known focus for urinary biliharziasis . According to the surveys carried out by the Inter-Institutional Committee in 1981 (pre-treatment) and in 1982 (post-treatment) the infection rates were 38.5Z and 18.3Z respectively (Ref 1). The same survey has also identified the existence of a big population of live Bulinus abyssinicus in che Korcume swamp which is considered to be the major site of transmission in the area. Perennial supply of water to this swamp which at present is said to be seasonal, would provide favourable breeding ground for snails all year round and thereby intensify the transmission of the disease. What is more, chemical control of the snail will be extremely expensive due to the large volume of water estimated to cover an area of 200-300 ha. In addition, the size of grazing ground would be greatly reduced by inundation. 42.1.2 Malaria Malaria is endemic in the entire Awash Valley, characterised by two seasonal transmission periods covering September to November and April to May of each year. The Malaria Control Programme has included 8 localities which are located in the Melka Sadi and Amibara areas in its routine control activities for malaria, ie, the settled population in those localities is being protected through the reduction of mosquito populations by means of residual spraying and also through the provision of antimalarial drugs. However, there is no consistent reliable programme outline to protect the nomadic Afar population of the area. Periodic entomological and parasitological activities are conducted to evaluate the impact of residual spraying on mosquito population and to determine the prevalence of malaria respectively. Entomological Activities Entomological studies were conducted by personnel of the Malaria Control Programme in Melka Werer observation post from 1980-1984. Day time adult resting collection, night time biting collection and larval collection was conducted (Table 1). Anopheles gambiae, A.pharoensis, A.funestus and other non-vector Anopheles Spp were found to breed in the observation post at Melka Werer. The data obtained by the three collection methods indicated a.gambiae to be the predominant species followed by A.pharoensis. Both A. gambiae and A.pharoensis have exhibited a strong tendency to rest in-doors (endophilic) and to bite out-doors (exophagic). Supplementary larval survey was conducted during the Inter-Institutional, Collaborative team's field trip to the area on November 10, 1984 from Tl-3, D4, C4, D5 & D6 locations and from Dahitele pump site. Second instar Anopheles Spp were collected from Tl-3 while the remaining locations were negative for Anopheles mosquitoes. However, Cuiex pipi ens (fatigans) were found breeding in all the examined sites. Water bodies in field, tertiary and secondary canals were not sampled for mosquitoes. 5Seasonal Blood Survey Seasonal blood surveys were conducted in eighc localities, namely, Melka Sadi, Amibara, Melka Werer, Asoba, Halidebi, Dahitele and Angelele. The surveys were undertaken from 1976 to 1984. Since all the localities were not surveyed during one single year, it is not possible to compare the prevalence of malaria in different parts of the project area. In general, the malaria situation in the project area seems to be stable with some degree of fluctuation. Plasmodium falciparum is the dominant species followed by P.vivax (Table 2). Spray Operations for Malaria Control DDT is the insecticide that is being used to spray human dwellings of all localities in the project area. During 1976 to 1984 some localities were sprayed ten times while others were sprayed only twice. The Anopheles mosquitoes in the project area are susceptible to DDT. Pesticides used in the farm areas Different types of pesticides are sprayed in the farm areas from insects, mites and weeds. In 1983/1984 alone, over 11 are sprayed in the farm areas (Table 3). The impact of the widespread use of these pesticides on insect species of public health importance is not known. The Public Health workers should periodically test the susceptibility of insect species to the insecticides used in’ the farm area, as the wide spread use of insecticides could lead to development of resis tance. Repeated exposure of pesticides may have cumulative toxic effects and would result in gradual onset of poisoning symptoms. Those workers handling pesticides as well as those people working in pesticide-treated areas are exposed to this risk. to protect the crops types of pesticides The existing irrigation system in Amibara and Melka Sadi areas has created large surface area of water bodies due to the extensive network of distribution and 6drainage canals. In addition, large ponds of stagnant water are allowed to be established in different parts of the project area as a result of improper water management practices. During the current field trip to the project area, it was evident that field, tertiary, secondary and primary distribution and drainage canal systems were covered with vegetation. Moreover, as stated earlier excessive pools of stagnant water were observed at Tl - 3 and the Dahitele Camp site as a result of seepage from distribution canals. These conditions have brought about the formation of habitats suitable for continuous breeding of mosquitoes and have created the potential for the occurrence of year-round transmission of malaria in the project area. Thus it will be fundamental to take into account the adverse impact the proposed drainage systems will have on the environment and on the propagation of malaria in the area. The proposed network of surface and subsurface drains to be constructed under Stage 1 of the Master Drainage Plan will utilise the existing Primary Drain Outfall (see Annex D). This drain flows into the Awash River and has provision for periodic overflows into Amibara Extension Area. Such intermittent overflow of drainage water into an open field will have a minimum negative health impact provided prolonged ponding does not occur. It is important that water bodies created by emergency overflows should not be allowed to stand for more than one week at any one location. For the development of the drainage system within the Amibara Extension Area three alternative methods of gravity disposal of drainwater were considered. The first method of routing all flows directly into Kortume swamps would have a negative health impact as it would create an environment of permanent breeding habitat for Anopheles mosquitoes and other species of public health importance. The second method is to discharge the drain into the Awash River with occasional emergency spillages into the Kortume swamp. While this alternative seems to be an improvement over the first, still the large volume of water that would be discharged into the swamp would be of health hazard. The third, and recommended, option is to direct all flows into the Awash via an unresticted confluence with the river some 12 km downstream of the study area. By this means the need for periodic overflows into Kortume is avoided and the associated negative impact eliminated. « 72.2 Water Quality 2.2.1 Chemical Chemical analysis of the irrigation canals, drainage canals and the Awash River at the intake conducted by the Water Resources Development Authority (WRDA) and measurements of conductivity and pH done during the field visit indicate that as far as the potability of the water is concerned, none of the measured constituents are beyond the acceptable limits put forward by WHO (Table 4). However, increased salinity was observed in the drainage canals compared to the river or irrigation canals - conductivity values of 3 fold being observed in the drainage canals compared to the irrigation canals (Table 5). The total discharge of about 100,000 kg of chloride equivalent of salt into the river between April and August alone, calculated from field data obtained by AIP Pilot Drainage Scheme Project (Table 6) indicates a high input of salt to Che Awash River which could also be augmented by Che proposed sub-surface drainage to be implemented (see Annex C). 2.2.2 Pesticide Levels There is no data available on the level of pesticides in Che area. However, the types of pesticides sprayed in Che area are known (Table 7). As far as we could see, none of them is persistent and all are believed co be biodegradable. It is however known by repute that toxicity to people and cattle drinking the canal water immediately after spraying is common. All the pesticides used are also known to be toxic. Thus there is a high risk Co people and animals using the canal and drainage water both from pesticides and from high salinity levels. 2.2.3 Eutrophication Surface or subsurface drainage and subsequent discharge of the water into the Awash River downstream is likely co increase Che level of nutrients in the river. However, the high turbidity of the Awash River will result in light limitation of growth 9uch that prolific growth of algae is not to be expected in che river. However, potential bloom-forming algae have been observed in Che river at che intake and in the irrigation canals (Table 8). 8u i i I I l l l to to I M3. RECOMMENDATIONS 3.1 Water Borne Diseases 3.1.1 Unnecessary collections of water like the ones adjacent to Tl-3 canal and the pump site in Dahitele should be avoided. Major depressions should be filled and spillways avoided whenever possible in order co prevent the formation of snail, mosquito and other disease vector habitats. In addition all habitats confirmed to harbour Bulinus abyssinicus should be destroyed. Furthermore, all existing water bodies and those to be created should be identified and located on a map for follow-up. 3.1.2 More frequent clearing of aquatic vegetations should be carried out, at least twice a year. At present vegetations are cleared once a year and it is apparently not sufficient. 3.1.3 A water velocity of 30 cm/sec as indicated in the design criteria, does not seem strong enough to cause snails to dislodge. It is therefore suggested Co increase the velocity to at least 40 cm/s and at the same time avoid sharp curves, make canal banks smooch and flat and keep the drainage system clear from vegetation growth to maintain a constant velocity. 3.1.4 The open drainage canals should be constructed far away (250-500 m) from labour camps and Afar villages to minimise man-water contact and contamination of the water by human excreta. New camps and villages co be built in Che future should be located far enough (500 m at least) from Che open ditches so that they don't give ready access to the canaL water. It is also desirable chat existing open drainage canals near or crossing human dwellings as in Melka Sadi and the bridge near the primary drain outfall be covered or fenced to minimise human/water contact or be lined w.ith concrete to discourage the breeding of vectors. 3.1.5 One of the major causes for the creation of unnecessary water bodies which favour the breeding of vectors is poor water management. It is therefore highly recommended that water management procedures and schedules be strictly enforced and supervised day and night. 93.1.6 Kortume swamp has to be kept dry to reduce the transmission of bilharzia and malaria in the Halidebi area. Therefore the option of routing the drain to skirt the Kortume flood plain and discharge into the river is preferred to the discharge of the drain and runoff water directly into the swamp. It is further suggested that part of the flow be discharged into wilderness at various sites so that more surface area will be soaked and conditions similar to controlled irrigated pasture created. This will not only increase the grazing ground and stop the Afars from diverting flood water, but also reduce the water spilled into the Kortume swamp. 3.1.7 Intermittent discharge of water into open fields could be acceptable provided the period of discharge is short and water from such discharge is not allowed to stand for more than one week at any one location. 3.2 Water Quality 3.2.1 Use of the canal or drainage water for drinking and domestic purposes should be avoided to prevent toxicity from pesticides and increased level of certain ions from fertiliser treatment. Safe water supply must be provided. 3.2.2 Provisions must be incorporated in the engineering design for the reduction of the salinity of the water before it is discharged into the river. This must be assessed in the context of a proper cost-benefit analysis of the system to be applied. 104. MONITORING ACTIVITIES AND PROCEDURES The major areas of concern that need periodic epidemiological and environmental surveillance in the project area are water related vector borne diseases and water quality. Among the vector borne diseases malaria and schistosomiasis constitute the major health risks while return flows containing excess salts, fertilisers and pesticide residues may give rise to pollution and contamination of the Awash River. 4.1 Water Borne Diseases In the monitoring of water borne diseases, emphasis is placed on schistosoma haematobium and malaria. The areas of concern are the vectors, ecology and human infection. 4.1.1 Schistosomiasis Base line data on the prevalence of schistosoma haematobium infection from Melka Sadi to Halidebi are available for 1981/82. Although it is unknown how the prevalence will change even without the Master Drainage Plan, studies and observations done during 1983/84 give reasonably good indication that at least within the Amibara Irrigation Project II and even extending up co Dahitele village, schistosomiasis transmission appears to have ceased. This area roughly corresponds to the present study area to be covered by the drainage plan. Using the 1981/82 data as a basis, yearly prevalence survey from 10Z of the population will be done which will indicate whether the disease is increasing or decreasing and the causes. Villages from Melka Sadi co Halidebi will be examined but emphasis will be given to villages from Hasoba to Halidebi, other villages being Dahiceli, Daknamo, Adengele and Deli. Urine filtration technique will be used for the examination and chose found positive will be treated. Praziquantel is the drug of choice because of few and minor side effects and ease of administration. Records from health centres and clinics in the project area will also be compiled for additional information. 11Malacological studies will also be undertaken and data to be collected will include the distribution of schistosomal infection of snails and their seasonal trend which are all essential in the formulation of a schistosoma control strategy. Bulinus abyssinicus and Biomphalaria pfeifferi are the two species of Lmmediate concern. 20 new snail collection sites were selected in November 1984 and these same sites will be used in this study and collection will be done once every two months. In addition, the area between Dahitele and Halidebi will be examined on a quarterly basis with particular attention to the Kortume flood plain. Major and frequent human/water contact sites will be identified especially near human dwellings and additional collection sites set up. Snails will be collected by scoop net. Bulinus and Biomphalaria species will be examined for schistosoma infection by shedding and/or dissection under the stereoscopic microscope. If S.haematobium or S.mansoni infections are found, snail control measures using chemical, habitat modification or both will be applied. If a large colony of B.abyssinicus is found near a village or camp site, control measures will also be applied even chough infected snails are not found. Bayluscide will be used as molluscicide. At each snail sampling site, the growth of aquatic vegetation, physical condition of the water body, water velocity, volume and temperature, nature of bottom whether gravel, sandy or muddy etc and any leakage or damage will be recorded. The information gathered will be useful in the evaluation of water management. Any finding with regard to unsatisfactory water management such as the formation of unwanted water bodies should be reported for corrective measures. The yearly prevalence survey and treatment of positive cases will be done by a team composed of a physician, epidemiologist, biologist, technicians and ocher paramedical workers. The ceam members will be drawn from the institutions and agencies which participated in this study. In addition all health centres and clinics in the project area will participate in the treatment of cases.Snail surveys, control and habitat observation will be done by the existing environmental health unit within the Amibara Project Control Centre. 4.1.2 Malaria The irrigation and drainage projects of Amibara and Melka Sadi are located in malaria endemic zone. The population within the project areas as well as the nomadic pastoralists in the surrounding sites are exposed to the risk of malarial infection. These sites are included in the Plan of Action of the National Malaria Control Programme (MCP) and are protected through the MCP’s routine control activities. The malaria situation in these areas is also being monitored and evaluated using standard entomological and parasitological indicators. However, due to the particular objectives of this project, the monitoring system should be strengthened to include the following activities. a) Entomological studies to monitor vector density and feeding and resting behavioural patterns need co be conducted on a regular basis. Personnel of the MCP will conduct such activities from the Melka Werer observation post on a monthly basis. b) Monthly larval survey of Anoph eles mosquitoes need to be conducted at various sites in the study area. Different components of the irrigation network such as primary, secondary and tertiary irrigation and drainage canals and all pools of standing water need to be sampled. It is recommended that sampling be conducted from randomly selected fixed sites. This will help to monitor the distribution of active breeding sites and also Che larval density in chose sices. These activities can be conducted by the sanitarian assigned to Che project area. The MCP will provide the necessary forms for Che larval survey and will train the sanitarian on sampling techniques. Collected larval specimens will be identified by Che MCP laboratory personnel at Nazareth Zone Office. c) Parasitological blood surveys need to be conducted during September-October of each year to monitor the prevalence rate of malaria during the peak transmission season. A sample size of 5 to 102 of the population from 13within and outside the project areas need to be sampled. Such activity will be performed by the MCP personnel. d) It is very important to monitor the malaria situation on a regular basis due to the high turn over of the labourers and the frequent movement of the nomadic pasturalists. Most of the labourers in the project area come from non-endemic areas and become targets for malarial infection. The existing health centres, stations/clinics found in the project area should be utilised in the monitoring and treatment of malaria cases. At present, fever cases who report to these health establishments are being treated for malaria without microscopical confirmation. It is strongly recommended that blood smears be taken from people who present themselves with fever in the various health establishments. The MCP will provide essential forms to be used by each health unit in order to maintain uniformity of recording, will examine the blood smears and provide results of microscopical examination to the respective health units. The sanitarian assigned to the project area should be the co-ordinator between the health establishments in the project area and the MCP. e) Other complex technical activities such as the monitoring of the sensitivity of antimalarial drugs and insecticides will be conducted by the MCP. 4.2 Water Quality Control 4.2.1 Areas of Concern There appear to be three areas of concern here: a) General impairment of water quality as a result of salinisation b) Eutrophication as a result of leaching of nutrients from the soil of the plantations c) Contamination of the water with pesticide residues A fairly simple monitoring scheme should suffice to deal with (a) above 14ic would perhaps be desirable co carry out periodic total analysis for major constituents (Na, Ca, K, Mg, alkalinity, chloride, sulphate) but routine measurements of conductivity would be sufficient to warn of any changes. Fairly simple routine analysis for phosphate, nitrate and ammonia should suffice for (b), along with occasional measurements of chlorophyl to indicate whether any added nutrients are having an effect. In such turbid water productivity is probably limited by light penetration so that even heavy nutrient loads might well have little or no effect on algal growth. The third area of concern poses a more difficult problem because Che nature and quantities of possible contaminants are known only in a general sense. It has been found elsewhere that the concentrations of contaminants in water are usually exceedingly small, so extraction and analysis of water samples might not be very informative. As a preliminary procedure it is suggested that specimens of fish and invertebrates be collected at several sites above and below the drainage outfall. These could be dissolved in concentrated HC1, and the resulting solutions extracted into a suitable solvent, such as dichloromethane, for analysis by gas chromatography. It might be necessary to use an electron capture detector, because the quantities would probably be below the limits of detection with a flame ionization detector. If contaminants are found, an attempt could be made to identify them either by mass spectrometry or by comparison of their retention times with those of known substances, a continuous monitoring programme could then be worked out on the basis of these preliminary results. 4.2.2 Recommended Monitoring In line with the above suggestions therefore, the following is recommended; (i) Chemical analysis should be conducted at sites formerly selected by the Health and Environmental Planning Department, WRDA, and also in the river downstream of the study area. The sampling locations are shown in the attached Figure 1. SampLing periods should be every six months, one in the middle of the dry season, and another in the middle of long rainy season. 15Responsible institutions are the Health and Environmental Planning Department and Biology Department, Addis Ababa University. In addition to the above six monthly chemical sampling and analyses the Project Control Centre (PCC) will undertake monthly electrical conductivity observations at the sample points shown on Figure 1. These observations should be made available to the Health and Environmental Planning Department of WRDA. (ii) Biological monitoring Sample sites at a) The main intake b) Irrigation canal preferably some place in the middle of AIP c) Drainage canal central area d) Drainage outfalls Sampling periods are every six months, one in the middle of the dry season and another in the middle of the rainy season. Responsible institutions are the Health and Environmental Planning Department and Biology Department. (iii)Analysis of pesticide residues Sampling of sites could be at several places, above and below the outfall. Sampling periods are every six months, one in the middle of the dry season and another in the middle of rainy season. Responsible institutions are the Health and Environmental Planning Department and Biology Department. 4.3 Institutional Arrangement The monitoring programme outlined in the previous section requires inter-sectoral and inter-disciplinary coordination and collaboration both at the local and central levels. The existing Inter-Institutional Committee which 16collaborated in this health and environmental impact study is the moat ideal group and will continue to participate in the monitoring scheme. The committee is composed of representatives from the Ministry of Health, (Central Laboratory and Research Institute, and the National Malaria Control Project), Water Resources Development Authority (Health and Environmental Planning Department), Addis Ababa University (Medical Faculty, Institute of Pathobiology and Biology Department) and Awash Corporation under the Ministry of State Farms Development. The role of these institutions and agencies in carrying out the various monitoring casks has been specified in the chapter dealing with activities and procedures. The Health and Environmental Planning Department of WRDA and the Environmental Health Unit in Amibara, in addition to their specific technical inputs, will have co-ordinating, programming, implementing and management functions. The local unit is supervised regularly by the Health and Environmental Planning Department and will receive technical assistance from the Institute of Pathobiology, the National Malaria Control Project and the Central Laboratory and Research Institute. The head of the local unit will promote and coordinate local activities in respect to health and environmental aspects of the drainage scheme. He will also facilitate the monitoring activities to be carried out by the Inter- Institutional Committee and will ensure the implementation of all recommendations arising from the monitoring process. Full liaison should also be maintained between the Water Management Unit of the Project Control Centre and the Environmental Health Unit in Amibara. The Health and Environmental Planning Department will prepare a plan of action and programmes, make Che necessary arrangements for financial material and logistic support and follow up of recommendations.4.4 Coses The major cost components are for schistosomiasis surveillance and water quality monitoring. Malaria surveillance in the project area will be part and parcel of the national malaria control programme and will not, as such, require additional expenses. Total capital and recurrent costs for water quality monitoring, schistosomiasis survey and control are 80,000 Birr and 20,000 Birr respectively. The cost breakdown by major component is depicted in Table 9. Costs to the project are greatly reduced because existing facilities at WRDA, Institute of Pathobiology and Addis Ababa University will be used free of charge. It is only those items of equipment and the supplies needed for field use that are included here. The major capital cost is for a vehicle for the Project Control Centre sanitarian at Amibara. All equipment and supplies have co be imported. In the recurrent expenditure, the foreign exchange component is about 20Z. All other costs are mainly for per-diem and maintenance.REFERENCES 1. An Inter-Institutional Collaborative Effort, August 1983, Urinary Bilharziasis Control in the Middle Awash Valley, Ethiopia. 2. Lemma A 1969, Bilharziasis in the Awash Valley, An Epidemiological Study with Special Emphasis on its possible Future Economic and Public Health Importance, Eth. Med. J. 7. 147 - 176. 3. Kloos H Polderman, A M G Desole and A Lemma. 1977. Haematobium Schistosomiasis among Semi-nomadic and Agricultural Afars in Ethiopia Tro Geog Med 29. 399 - 406. 4. Arfaa F 1975. Studies on Schistosomiasis in Somalia Am J Trop Med Hyg 24. 280 - 283. 19TABLE 1 - MALARIA CONTROL PROGRAMME - OBSERVATIONS Day time collection Melka Warer Station (Observation Post) A-gambia A.fun A.Nili A.phar A.others Slides Year in out in out in out in out in out Coll pos Z 1980 0 00 00 0 0 0 0 265 0 0 1981 1252 11 19 0 00 154 0 0 0 7715 11 1.54 1982 1136 0 16 0 00 75 0 0 0 922 57 6.18 1983 2208 4 10 00 61 1 11 0 977 25 2.61 1984 250 1 30 00 28 1 1 0 1799 28 1.56 TOTAL 4847 16 39 0 00 318 2 12 0 4678 121 2.59 Night biting collectio n result 1980 18 36 00 00 .7 30 0 0 1981 243 401 02 00 64 219 0 0 1982 113 320 00 00 23 71 1 4 1983 161 353 02 00 40 140 17 86 1984 105 340 30 00 48 175 11 24 TOTAL 640 1450 34 00 182 736 29 114 Larval collection result Year A.gambia A. fun A.nili A. phar A.others 1980 18 0 0 1981 59 0 16 0 0 1982 197 0 45 25 0 1983 120 4 92 0 0 1984 191 0 136 21 0 198 65 TOTAL 585 4 0 487 111 (source - Malaria control programme - Entomology Section) 20TABLE 2 - DISTRIBUTION OF MALARIA PARASITES BY SPECIES & LOCALITY (Source ~ Malaria Control Programme—Statistics Section) 1981 - Locality S.Exam Pos Mix F V M Melka Sadi 100 10 - 9 1 - Amibara 111 7 - 7 0 0 Melka Warer 99 0 — — — Asoba - • — — — Alidebe - — — — — Alikuda • 108 4 - 3 1 — Ditele - — — — Angelele ■ TOTAL 418 21 - 19 2 0 1982 - Locality Melka Sadi 122 0 0 0 0 0 Amibara - - - — - - Melka Warer 94 1 - - 1 - Asoba - - - - - - Alidebe 69 1 0 1 0 0 Alikuda - - - - - - Ditele - - - - - - Angelele — — — — TOTAL 285 2 0 1 1 0 1983 - Locality Melka Sadi 100 3 0 0 3 0 Amibara 112 0 0 0 0 0 Melka Warer 65 1 0 0 0 1 Asoba - - - — — Alidebe - - — — — — Alikuda - - - — — Ditele 18 1 0 1 0 0 Angelele 41 3 0 3 0 0 TOTAL 336 8 0 4 3 1 1984 - Locality Melka Sadi 113 2 Amibara 1 1 107 0 __ Melka Warer i30 0 Asoba 133 9 — Alidebe - — __ 2 1 Alikuda 114 2 - Ditele - — 1 1 Angelele - - - * - - TOTAL 597 13 0 4 3 - 21TABLE 3 - PESTICIDE USAGE IN THE MIDDLE AWASH AGRICULTURAL ENTERPRISE AREA FOR 1983/84 CROP YEAR (FIVE FARMS) PEST TYPE OF PESTICIDE QUANTITY HECTARAGE Spider Mite Mitac 20Z EC-ULV 13200 litres 4360 Spider Mite Tedion V-At 8600 litres 4360 Sucking Pest Dimecron 100 SCW 2535 litres 6228 Sucking Pest Roger ULB 18600 litres 18684 African Bollworm Thiodan 25 ULV 93420 litres 31140 African Bollworm Curacron 250 EC-ULV 18600 litres 6228 African Bollworm Nuvacron Olver Cumbi C500 18720 litres 6228 African Bollworm Decis 0.6Z ULV 31200 litres 12456 White Flies Mitak 20Z EC-ULV 48600 litres 16193 White Flies Thiodan 35Z EC 4500 litres 2491 Leaf Worm Dursban 24 ULV Spring, Pink Sudan Bollworm Azodrin 40 WSC Complex Weed Complex Weed Ronstar/Divron Codal 400 EC 44928 litres 12383 litres 3000 litres 6500 litres 9965 6228 1000 1000 Actual Sprayed Area up to October 10/1984 Melka Sadi Melka Werer Amibara Dofan Bolhamo Gewani 15246 Hectares 23353 Hectares 21158 Hectares 18243 Hectares 13200 Hectares TOTAL 91200 Hectares Spray Rounds - 6.08 (Source - Awash Agricultural Corporation)TABLE 4 - WHO STANDARD OF POTABLE WATER (1979) I PHYSICAL AND CHEMICAL CHARACTERISTICS I WHO STANDARD MAXIMUM ALLOWABLE Colour 1 300 (Platinum Cobalt Unit) 11 Total Solides •1 1500 mg/1 11 Taste 1 Acceptable 11 Odour 1 Acceptable 11 Hardness 1 11 500 mg/ml Iron 1 50 mg/1 11 Manganese 1 1 5 mg/L Copper 1 11 1.5 mg/1 Fluoride 1 11 1.5 mg/1 Nitrogen as NO3 11 1 45 mg/1 Silicate 11 1 20 mg/1 Phosphate 1 1 — 23TABLE 5 - CONDUCTIVITY, pH AND DISSOLVED OXYGEN IN SELECTED IRRIGATION CANALS AND DRAINAGE CANALS IN THE AIP AREA II I (Date of Sampling; 10 November 1984) I Location Conductivity in utnho PH Oxygen mg/1 I 1. Swamp (Tl-3) 255 - - 2. Tertiary Drains - 400 - - I pilot drainage area 3. Awash River - near intake 275 - - I 4. D3 490 7.86 16.6 5. C4 275 7.5 11.3 6. D5 750 7.5 8.4 ■ ■ 7. D6 470 8.0 9.8 8. Awash Downstream 550 I 0 I H h l i ■ ■ ■ ■TABLE 6 “ AIP PILOT DRAINAGE SCHEME - DRAINAGE DISCHARGE FIELD RECORD Volume of Discharge in m^/month —1-------------------- i r---------------------- 1----------------------1--------------------------- MONTH I DI - D5 1 1 D16 - D26 1 D27 - D34 I Total monthly 1 1 1 1 1 1r April 84 1 1 I 4685.34 | I1 1819.29 1 1 6504.63 | | May 84 I 4616.34 I 1 1 11 6127.82 1 1245.90 |1 1 11990.06 June 84 1 4216.19 1 1 1i 1 5178.60 1 1790.85 11185.64 11 11 July 84 1 2789.23 | | 1 3646.38 I 1 1542.99 1 7978.60 i1 August 84 1 3353.95 I 6693.18 1 1735.29 1 11782.42 1 1 Total volume discharged from April - August 84; 49441.35 m^ 11 1 Assuming a concentration of salt of 2.05 gms/litre as a mean value then the discharge of salt during the period is; 49.439 x 106 x 2.05 gms = 101.33995 x 106 gms - 101,339.85 kgTABLE 7 - LIST OF PESTICIDES USED IN TIBILA, AWARA MELKA, MILLE, DUBTI AND DIT BAHRI STATE FARMS OF THE AWASH VALLEY - JANUARY 1984 Serial No Name of Pesticides 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Aldnix 48Z Azodrin (DDT) 10/40 Anthio Anetellic Acarin Bastudin 600 EC Cymbush Curacron Cidial 85 AS Dursban 40 ULV Dimecron 100 SCW Decis Di Cane M-45 Ekachin 24 ULV Exactin WE Ethion 50 ES Endrin 1.6 ULV Fertilion Combi Gusathion Koicide 101 Hosathion Metasystox R50 Medopar Mencozev 80Z WP Nuvacron 40, SEW Perfecthion Parthion 50Z Quel cox Ripcord Roger 40 ULV Round up Santara Servin Sulv Sunicion 50 EC Safsan Thiodan 25 ULV Thionex 25 ULV Tiezene 80 Torbidan Tamaron Ulcracide Ulvair Combi 500 Volt CusthacionTABLE 8 - ALGAL FORMS IDENTIFIED IN WATER SAMPLES COLLECTED IN AIP ON NOVEMBER 10, 1984 Station D3 Diatom Dominating a Spiro’gyra sp b Cyclotella sp c Navicula sp d Pinnularia sp Station D$ (main outlet) Diatom Dominating a Navicula sp b Scenedesmus sp c Pinnularia sp d Epitheraia sp e Neidium sp f Caldophora sp Station C4 a Microcystis sp b Oscillatoria sp c Navicula sp Station D5 Diatom Dominating a Scenddesmus b Navicula sp c Microcytis sp Station Rj a Navicula sp b Melosira sp c Volvox sp d Tetraspora sp Station Awash River Down Stream a Navicula sp b Cyclotella sp d Scenedesmus sp e Occystis sp f Merismopidia sp g Microcystis sp h Oscillatoria sp e Cyclotella sp f Peridinium sp g Mougeotia sp h Oocystis spTABLE 9 - CAPITAL AND RECURRENT EXPENDITURE FOR HEALTH AND ENVIRONMENTAL MONITORING, ANIBARA AND MELKA SADI MASTER DRAINAGE SCHEME Cost in Birr COMPONENTS Capital Recurrent Schistosomiasis a) Equipment and Supplies 10,000 10,000 b) Snail Control 40,000 6,000 Water Quality a) Equipment and Supplies 30,000 3,000 b) Laboratory Analysis - 1,000 (Pesticide residue) TOTAL 80,000 20,000 . 28FIGURESI I I I I Ik ■ » n n ■ ■ ■ ■ ■ ■appendix a TERMS OF REFERENCEMASTER DRAINAGE PLAN FOR MELKA SADI AND AMI BARA AREA APPENDIX A - TERMS OF REFERENCE 1. TERMS OF REFERENCE 1.1 Amplification of Requirements 2. PROPOSED FUTURE DRAINAGE PROJECT 2.1 Subsurface Drainage of Immediate Priority Area in Melka Sadi 2.2 Subsurface Drainage of Immediate Priority Area in Amibara 2.3 Final Development Stage1. TERMS OF REFERENCE The Specific Terms of Reference which relace to these aspects of the study are reproduced below. These are, TOR 17 ’’Prepare methods of monitoring of the quality of surface drainage (tail-water), levels of pesticides, etc". and TOK 18 ’’Establish monitoring system for environmental health hazards such as biliharzia and malaria incidences”. 1.1 Amplification of Requirements 1.1.1 Considering TOR 18 first, the results of Che current monitoring programme which, reportedly, constitutes regular sampling and snail counts within the existing canals and drains of Che AIP II project area should be summarised and reviewed in the particular content of assessing the current prevalence of diseases, the existance of favourable habitat for snail propagation or malaria breeding and also for ocher water borne diseases which currently exist or could be catalysed by the conditions of these watercourses. In many sections of Che project area there is a high incidence of water stagnation and pollution, induced by severe and unrestricted weed growth and by human or animal contamination. The study should identify and isolate the worst affected areas and make clear recommendations on the necessary works to be executed to eliminate or minimise these hazards. For presentational purposes the use of project plans for locating existing monitoring points and for indicating the presently contaminated or hazards areas would seem expedient (Fig 1). 301.1.2 Arising out of this study recommendations for the continuation of a detailed monitoring programme, indicating sampling locations, procedures and analyses required would be prepared, adapting or retaining the existing monitoring programme as appropriate. 1.1.3 Recommendations should be made on the organisational aspects of such a monitoring programme, identifying the Body most appropriate to be responsible for the execution of this programme and the procedural aspects for ensuring that recommendations of this Body can be enforced. 1.1.4 The study would also outline Che guidelines for the treatment of potential or actual hazard areas within Che project. 1.1.5 The results of this phase of the study would be assessed in the context of the design standards to be adopted for the proposed drainage project, where existing conditions indicate that changes to currently accepted design practices would be expedient in the light of local conditions and experience. A specific example to illustrate the above would be the consideration of using deep buried pipe drains for the conveyance of sub-surface drainage flows at secondary and tertiary drain level instead of deep open channels where perennial flows, combined with inadequate maintenance, could constitute an unacceptable health hazard. 1.1.6 Under TOR 17 the Consultants field team will review the expected levels of salt content and the residual salinity concentrations in the Awash and main drains downstream of Che project together with the potential effects of this on downstream users. Selected monitoring points for water quality sampling will be determined. The WRDA team would by reference to or involvement of other specialists as necessary, determine the indices of contaminants of pesticides etc which should be monitored and assess the current secondary effects of such applications in relation to their potentially deleterious biological effects. 312. PROPOSED FUTURE DRAINAGE PROJECT For the proposed drainage project several phases of implementation are currently envisaged. These are, 2.1 Sub-surface Drainage of Immediate Priority Area in Melka Sadi Sub-surface drainage within parts of the immediate priority areas^ in Melka Sadi utilising the existing main drainage network within the AIP II project area. The current conditions relating to the discharge of the main drainage flows into the Awash under low Awash levels with emergency, short duration, overflows into the Amibara Extension area would essentially remain unchanged apart from recommendations for minor improvements to prevent localised flooding in the village and farm areas immediately downstream of the existing emergency spillway on the Primary Drain extension. Any health implications arising from the present situation should be assessed so that engineering modifications to the system can be recommended as appropriate. Similarly the implications, if any, relating to the intermittent discharge from the Eastern Catchment Drain into the uncultivated areas downstream should be assessed and suitable monitoring points determined on this drain and its downstream area to allow continued observation and evaluation. 2.2 Sub-surface Drainage of Immediate Priority Area in Amibara 2.2.1 The drainage of this area would require the construction of a new primary drain which would be routed through the Amibara Extension area and discharge by gravity to the Awash during low river levels. As occurs with the existing drainage system during high river levels, this new primary drain would occassion emergency, short duration, overflows into the uncultivated Angelele lands downstream. Health implications arising from this system would be essentially similar to those relating to 2.1 above, such that any recommendations relating to the existing system would equally relate to this stage of development. 1/ Discussion Paper, Section 4.1 and Figure 4.12.2.2 Similarly the Eastern Catchment Drain would be extended past Bilen Swamp and discharge, during periods of rainfall generated runoff, into Angelele. 2.3 Final Development Stage 2.3.1 The final stage of development would occur when subsurface drainage of the project up to its northern boundary is required. Removal of this subsurface water by gravity would necessitate the construction of a drain through Angelele. This drain can be routed directly into Kortume Swamp, thereby effectively providing a perennial supply of water to the Swamp area. Removal of excess flows from the Swamp would be effected by an outlet drain to the Awash, in the vicinity, or downstream of, Halidebi Settlement. 2.3.2 Alternatively the drain can be routed to skirt the swamp and discharge by gravity back into the Awash, with occasional emergency spillages into the Swamp area when high Awash levels do not permit gravity drainage. Flows directed into the Swamp would accordingly be of an intermittent nature only, insufficient to induce perennially flooded conditions. 2.3.3 The health implications of the alternatives in the final stage of development should be assessed, in particular the aspect of maintaining perennial flows through Kortume. The extent of the flooded area cannot be readily assessed at this stage of the study but consideration could be given to a body of water covering 200 - 300 ha which could drain down to effectively zero during low river stages when through drainage can be effected. 33APPENDIX B LIST OF PARTICIPANTSAPPENDIX B - LIST OF PARTICIPANTS 1. Dr Fissha H/Meskel 2. Tilahun W/Michael 3. Dr Awash T/Haimanot 4. Dr Amiha Belay 5. Prof Vaxter 6. Prof Harrision 7. Melaku Mesfin 8. Fekade Tsegaye 9. Hailu Negero 10. Kemal Zekaria 11. Bekele Desta 12. Dr C T Lo 13. Hailu Birre Central Laboratory and Research Institute Central Laboratory and Research Institute Ministry of Health Addis Ababa University Addis Ababa University Addis Ababa University Addis Ababa University Water Resources Development Authority Water Resources Development Authority Water Resources Development Authority Water Resources Development Authority Institute of Pathobiology Institute of PathobiologyDote Due AUTHOR TITLE
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