Community-based traditional irrigation schemes performance: A case study of Upper Awash River Basin of Addis Ababa sub-catchments

Tadesse Bekele,¹ Girma Taddese² and D. Peden²

1    Ministry of Agriculture (MoA), Addis Ababa, Ethiopia
2    International Livestock Research Institute (ILRI), P.O. Box 5689, Addis Ababa, Ethiopia

Abstract

Introduction

The study area

Results

Discussion

References

Abstract

The study was carried out in Addis Ababa sub-catchments along the Akaki River. The Akaki River is a tributary of Awash River in Upper Awash Basin with its two main catchments (Little Akaki and Big Akaki River) which drain into Aba Samuel artificial reservoir. The traditional irrigation schemes grow vegetables along the Akaki River and supply about 30% of the vegetable demand for Addis Ababa city. The water management in the schemes was very poor and some of the traditional irrigations schemes are located in the river course and face frequent over-flooding during the heavy rains season. Besides, there is great concern over the use of fresh vegetables from these schemes as they are irrigated with municipal wastewater. Some factories dump waste products and water directly to the river without treating. The concentration of heavy metals and coliforms is increasing below Aba Samuel dam, an outlet of Akaki River. The overall information showed that farmers get adequate benefit from traditional irrigation and own dairy cows. Finally the Addis Ababa sub-catchments community irrigation activity should be thoroughly studied for the benefit of the Addis Ababa community.

Introduction

The Awash River Basin is divided into Upper, Middle and Lower Awash basins. According to Zewdie (1994). Awash River starts at an elevation of about 3000 metres above sea level (masl) in the central Ethiopian highlands, west of Addis Ababa and flows north-east along the Rift Valley into the Afar triangle where it terminates in Lake Abe at an elevation of 250 masl. The main river length is about 1200 km.

The Awash Basin covers a total area of 110 thousand km² and covers the regions of Oromia, Afar, Amhara, Addis Ababa City Administration and Dire Dawa Council. Awash Basin is an intensively used river basin in Ethiopia due to its strategic location, access roads, and availability of land and water resources. Currently 21,865 ha traditional and 4932 ha modern small-scale irrigation schemes have been developed. Irrigation potential in Awash Basin is estimated to be 206 thousand hectares (Table 1). However, the basin suffers from severe environmental degradation, annual flooding, improper use of land, and water resources, socio-economic constraints, poor agricultural practices, low yields and community health problems. Thus this paper assesses the performance of existing community-based traditional irrigation schemes in Upper Awash Basin. It also studies the water use efficiency of traditional small irrigation schemes in Addis Ababa catchments and the economic benefit of traditional small-scale irrigation schemes.

The study area

The study was carried in Addis Ababa sub-catchments along the Akaki River. The Akaki River is found in Upper Awash Basin with its two main catchments (Little Akaki and Big Akaki rivers) which drain into Aba Samuel artificial reservoir. In the sub-basins of Awash Addis Ababa catchments, there are more than nine perennial river tributaries, which drain to main Akaki River. The catchment's area is estimated to be 137 thousand hectares. The studied schemes varied in size from 4 to 150 ha. Four of the schemes have water pumps with a capacity of 30 l/sec. The farmers are organised in traditional way of water users associations. Each irrigation scheme has water committee. The water committee is responsible for water administration and management, co-ordinating, operation and maintenance of canals and resolution of disputes among beneficiaries.

Membership includes both men and women and consists of 1574 family heads and 7630 families. Out of these 28% are women farmers. The farmers manage operation and maintenance works of their schemes.

Along the right and the left sides of the Akaki River, 389.5 ha of land is developed under traditional small-scale irrigation system (Table 1). The traditional irrigation schemes grow vegetables along the Akaki River.

The major soil types of the study area are Pellic Vertisols and Nitosols. Pellic Vertisols that are found at Akaki, just south of Addis Ababa, has too shallow soil depth at 3% slope with surface cracking features. Nitosols are found in the highland of Addis Ababa to the north-east of the catchments. Nitosols have very good potential for agriculture and have high water storage capacity.

The catchments have favourable climate for certain vegetable crops. The traditional irrigation water delivery system, irrigation frequency and water management systems are very poor. More often the farmers spend their time in maintaining canals, which they have to build every season after the small and big rain seasons.

Major crops grown

The major vegetable crops grown in the schemes are lettuce, Swiss charade, carrot, kale, cabbage, potato, zikuni (cucumber), cauliflower, beans, tomato, pepper and onion. About 85% of improved vegetable seeds are supplied by Agricultural Input Services Corporation (AISCO) and the remaining 15% seed bulk is grown and supplied by farmers themselves (Table 2). Table 3 shows the recommended improved vegetable suppliers.

Crop water need

The Pen Man Montith method was used to calculate reference evapotranspiration (ETo) and Effective rainfall (Re) was calculated using USDA Soil Conservation Service method. Crop water requirement (ETc) is calculated by the formula (ETc = ETo × Kc) and field efficiency is taken as 60%. Net irrigation (In) was also calculated as In = ETc – Re and approximate net irrigation depth per irrigation application was taken by assuming the root depth of each vegetable crop and soil type of the study area. Number of irrigation application was calculated from: irrigation water need over growing season/net depth of each irrigation application.

Economic calculations

                Total cost = Labour cost (ETB/ha) + Seed cost (ETB/ha)

                Net production (qt/ha) = Productivity (qt/ha) –15% production losses

                Total income (ETB/ha) = Net production (qt/ha) × Market price (ETB/kg)

                Net income (ETB/ha) = Total income (ETB/ha) – Total cost (ETB/ha)

                Feasibility ratio = Net income (ETB/ ha)/Total cost (ETB/ha)

Discussion

Ethiopia is endowed with rich water resources, but yet untapped natural resources that could have largely contributed to the overall national economic development on a sustainable basis. Ethiopian agriculture is mainly rain fed, which is erratic. As a result of recurring drought, shortage of food and malnutrition became the main features of the country. Current agricultural strategy and policy of the government promotes irrigated agriculture in all potential river basins. The modern small irrigation schemes and traditional irrigation are sustainable and are easily manageable by farmers.

The key factor for the development of small-scale irrigation around Addis Ababa city is the large demand for fresh vegetables for the local market. However, vegetables grown under traditional irrigation schemes and the yield obtained are not so high due to poor agronomic practices, lack of technological inputs, and low level of water use efficiency.

Most of the scheme sites are found along the river mouth and exposed to flood hazards. During the rainy season, the fields are water logged and are not used for crop production. Traditional irrigation also faces common problems such as paucity in land holding, insufficient capital, inequitable water use and social conflicts in water use.

Irrigation water scheduling also is not well practiced and there is a possibility of applying excess water to crops beyond the crop water requirement. At the beginning of the growing season, the amount of water given per irrigation application, or the irrigation depth is small and is given frequently. Farmers who live around Addis Ababa are within the orbit of the existing market information system and get reliable sources of income.

The development of irrigated agriculture around Addis Ababa city needs a systematic cost–benefit analysis and the realisation of profitability for market-oriented production and the attainment of sustainable development. The market-oriented irrigated agricultural activity in general should consider proper estimation of labour, transport, maintenance, store, operation and investment costs in their cost–benefit analysis to optimise profitability. It should also give priority to the demand of the market in planning and producing vegetable products.

Farmers in irrigated schemes got better market access to income than that of rain-fed farming (Table 6). This gives every reason for the policy makers to channel more concern to smallholder irrigation development.

Despite its success and growing importance of peri-urban and urban small traditional irrigation, it is still subject to numerous constraints. Among them are insufficient access to non-contaminated or clean water, uncertainty about land tenure, and poor water use efficiency. The majority of beneficiaries hold less than 0.5 ha per household and land fragmentation has been the basic problem for irrigation development. Most of the farmland is found along the riverbed where irregular flood hazard can easily wipe out the farmland and high losses of water. Main feeder cannels are often poorly constructed and maintained and have poor water distribution system within the potential command area. This takes considerable amount of time, efforts and money to make them productive. The schemes lack proper maintenance and reconstruction of the headwork and are subject to uncontrolled use of water for irrigation. There is high loss of irrigation water in the traditional irrigation schemes when crossing gullies. Frequently inequitable distribution of water between upstream users and down stream users causes conflicts.

Women perform important agricultural activities such as seeding, weeding, harvesting, threshing, mulling and other related works. In areas under study, women's participation in the irrigation schemes is encouraging. There is equal farm level access to water and related obligation, equal participation in forums or network for collective water management and fair gender composition at the leadership level in the water users associations. In addition to growing vegetables, farmers have also livestock used for various purposes. Women play greater role in holding dairy cows than men in the schemes. The milk is supplied to the town and milk-processing factory in Addis Ababa.

Measures to boost agricultural production play a very important role in achieving development policy goals by reducing food insecurity, and increasing incomes and employment opportunities.

Expansion of new industries and disposal of industrial wastes to the Awash River Basin is of great concern to the nation (Girma 2001). Food and beverage factories tend to discharge heavy organic pollutions. Textile factories discharge dyes. All these disposals are dumped to Akaki River, which is the main tributary of Awash River. This river is the main source of irrigation water in the studied traditional community-based irrigation schemes, and supplies 30% of vegetable to the city. In this regard, the issue of health is critical in urban and peri-urban agriculture where water is polluted by industrial wastes, while application in farming of such untreated waste can pose significant health risks both to those who have direct contact with it and also to the general public who are affected through the food chain link (Furedy et al. 1999).

Small-scale irrigation schemes in the sub-basin leave much to be designed in terms of efficient water use and prevention of harmful conditions resulting from water logging and pollutant of heavy metals. It will be necessary to introduce better irrigation methods and water management techniques. Diversion of perennial river, harvesting and storage of water from frequent flash floods, and the use of ground water for irrigation should be targeted for future agricultural development and food security. In Ethiopia, as in the rest of Africa, many irrigation projects have proved to be unsustainable. Co-operation was unpopular with peasants and many were reluctant to invest their labour and energy in the irrigation venture.

All too often, state agents harbour strong paternalist attitudes towards peasants. There is frequently a tendency on their part to define the rules and set the guidelines governing irrigation schemes without involving the peasants.

Water security, like land tenure security, requires that users must have reliable and timely access to water adequate for their needs.

References

Alemtsehaye Biru. 2002. Assessment of the fertility and pollution status of irrigated vegetable framers around Addis Ababa. Addis Ababa City Government Agricultural Office, Addis Ababa, Ethiopia.

Furedy C., Maclaren V and Whitney J. 1999. Reuse of waste for food production in Asian cities: Health and economic perspectives. In: Koc M., Macrae R., Mougeot L.J.A. and Welsh J. (eds), For hunger-proof cities. IDRC (International Development Research Centre), Ottawa, Canada. pp. 136–144.

Girma Taddese. 2001. Land degradation: A challenge to Ethiopia. Environmental Management 27:815–824.

Zewdie Abate. 1994. Water resources development in Ethiopia. An evaluation of present experience and future planning concepts.