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Water resources and irrigation development in Ethiopia

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Sourced from Ethiopian Herald here: 

http://www.ethpress.gov.et/herald/index.php/herald/development/3348-water-resources-and-irrigation-development-in-Ethiopia

 

Ethiopia is the second most populous country in Africa (Awulachew et al. 2005). According to the Central Statistical Agency of Ethiopia projection (CSA 2005) from the 1994 census, the total projected population in Ethiopia for 2006 was estimated to be 75,067,000, about 85 percent of which lives in the rural areas depending on subsistence agriculture.

Ethiopia covers a land area of 1.13 million km2, of which 99.3 percent is a land area and the remaining 0.7 percent is covered with water bodies of lakes (MOWR 2002). It has an arable land area of 10.01 percent and permanent crops covered 0.65 percent while others covered 89.34 percent.

According to the World Bank, the per capita income in 2005 was $160 per year. The agricultural sector is the leading sector in the Ethiopian economy, 47.7 percent of the total GDP, as compared to 13.3 percent from industry and 39 percent from services (World Bank 2005).

Though agriculture is the dominant sector, most of Ethiopia’s cultivated land is under rainfed agriculture. Due to lack of water storage and large spatial and temporal variations in rainfall, there is not enough water for most farmers to produce more than one crop per year and hence there are frequent crop failures due to dry spells and droughts which has resulted in a chronic food shortage

Ethiopia has an extremely varied topography. The complex geological history that began millions of years ago and continues, accentuates the unevenness of the surface; a highland complex of mountains and bisected plateaux characterizes the landscape. Interspersed with the landscape are higher mountain ranges and cratered cones. According to some estimates about 50 percent of African mountains, about 371,432 km above 2,000 meters, are confined within Ethiopia (FAO 1984). Altitude ranges from 126 meters below sea level in the Dalol Depression on the northern border, to the highest mountain, Ras Dashen in the Semien Mountains north of Lake Tana rising

to 4,620 m.a.s.l. The plateau in the northern half of the country is bisected by the Ethiopian Rift Valley, which runs more than 600 km north–northeast of the Kenyan border to the Koka Dam on the Awash River south of Addis Ababa. The rift then descends to the northeast and its lateral escarpments begin to diverge from each other crossing the Afar Depression towards the Red Sea coast (Ayenew et al. 2005).

Based on Global Precipitation Climatology Centre (GPCC http://gpcc.dwd.de) data, we have derived climatological data. Accordingly, the mean annual rainfall is 812.4 mm, with a minimum of 91 mm and a maximum of 2,122 mm; with a highest rainfall ranging from 1,600–2,122 in the highlands of the western part of the country, and a lowest rainfall from 91-600 mm in the eastern lowlands of the country. The mean annual temperature is 22.2 degrees celcius. The lowest temperature ranges from 4-15 degrees celcius in the highlands, and the highest mean temperature is 31 degree celcuis in the lowlands at the Denakil Depression.

It is expected that through an optimal development of water resources, in conjunction with development of land and human resources, a sustainable growth of food production can be achieved.

Since the mid-1980s, the Ethiopian government has responded to drought and famine through promoting and construction of irrigation infrastructure aimed at increasing agriculture production.

These are traditional, small, medium and large-scale irrigation schemes performing at different levels.

Irrigation development has positive socio-economic and some negative environmental impacts. Formally accounted overall irrigation development is estimated at some 5 – 6 percent of the developable potential of 3.7 million ha.

The irrigation area in year 2002 was 197,000 hectares with a coverage distribution of 38 percent traditional, 20 percent modern communal, 4 percent modern private and 38 percent public schemes(MoWR 2002). The revised figure puts the total irrigated area at about 250,000 hectares (Awulachew

et al. 2005). This number gives a per capita irrigated area of about 30 m2. This value is very small compared to 450 m2 globally. The targeted growth expansion (according to the 2001 Water Sector Development Plan), is also not significant and not expected to bring a significant change and the much-needed economic growth. Considering the population growth as per table 1 and the targeted development of the 2002 water sector development strategy, the per capita irrigated area only reaches 45 m2 per head by the year 2015 and does not move the sector significantly. Therefore, given extreme meteorological and hydrological variability in Ethiopia, it is important that significant attention be given to enhance better water control, use and management of the water resources for agricultural production through irrigated agriculture. Corollary to this, the revised strategy, according to Plan for Accelerated and Sustained Development to End Poverty (PASDEP) (MOFED 2006), puts the large and medium-scale irrigation growth by year 2010 at an additional 493,000 hectares, which is an improved plan on previous strategy.

The project related to this paper known as “Impact of Irrigation on Poverty and Environment (IIPE)” is sponsored by the Austrian Government to be executed by the International Water Management Institute (IWMI) in collaboration with Austrian and Ethiopian Universities, Research Institutions and relevant ministries in Ethiopia. One of the expected outputs of the project is to establish a comprehensive data and information database on irrigation and drainage sub-sector.Often the availability of reliable and consistent data and information on surface and ground water is one of the basic requirements for development, use and management of water resource, in order for water managers to make well-informed decisions, as well as for researchers to make proper analysis and arrive at reasonably accurate conclusions.

In Ethiopia, the major problems associated with the generation of reliable data and information on water resources management consists of a lack of consolidated strategy, including institutional linkages, processes of collection, storage, analysis, and dissemination. A clear example of this is the lack of consistent and reliable figures on irrigated agriculture from various sources in Ethiopia.

Recognizing this fact and in an effort to contribute to the knowledge base of the water sector of the country, IWMI (together with other partners) has conducted a survey on existing small, medium and large-scale irrigation developments in Ethiopia and created a database in Geographic Information System (GIS). The creation of this database on irrigation and drainage is the first of its kind in putting together the existing data in an organized manner and make it available for end users.

The database contains spatial data of river basins, river networks and existing irrigation schemes (small, medium and large-scale) in each administrative region of Ethiopia; and the potential that can be realistically irrigated in each river basin. Although the already developed database is a very useful output, it is considered as an evolving working document which will be updated from time to time as additional information and recent developments emerge. The accompanying sections therefore discuss the general water resources information of Ethiopia and specifically discuss the potential and development of irrigation identified by regions and basins as well as aggregate values at national level. As much as possible, the irrigation potential and development are geo-referenced and mapped in GIS environment. The resulting Geospatial Database, maps and Microsoft Access database, which are already shared with regional government bureaus and federal ministries, can provide invaluable and harmonious information systems that can be updated from time to time, as new schemes are put in place.

Water resources

Surface water resources: river basins

The country has 12 river basins. The total mean annual flow from all the 12 river basins is estimated to be 122 BMC (MoWR 1999). This could be further refined when data on recent master plan studies becomes available.

At present, surface water and meteorological data are collected and processed on a regular basis through existing hydro-meteorological networks.

The idea of a river basin, despite its physical or natural attributes, is more than an engineering concept and encompasses the magnitude and dynamics of a resource that must be harnessed for the common good (Molle 2006). It has often been advocated that the most logical unit for water resources planning and optimum utilization of available water resources is the river basin.

Accordingly, it is desirable that all major river basins in Ethiopia have an integrated development master plan study, and their potential in terms of economic development be known.

Surface Water Resources: Lakes and Reservoirs

Ethiopia has 11 fresh and 9 saline lakes, 4 crater lakes and over 12 major swamps or wetlands. Majority of the lakes are found in the Rift Valley Basin. The total surface area of these natural and artificial lakes in Ethiopia is about 7,500 km2. The majority of Ethiopian lakes are rich in fish.

Most of the lakes except Ziway, Tana, Langano, Abbaya and Chamo have no surface water outlets, i.e., they are endhoric. Lakes Shala and Abiyata have high concentrations of chemicals and Abiyata is currently exploited for production of soda ash.

As compared to surface water resources, Ethiopia has lower ground water potential. However, by many countries’ standard the total exploitable groundwater potential is high. Based on the scanty knowledge available on groundwater resources, the potential is estimated to be about 2.6 BMC (Billion Metric Cube) annually rechargeable resource; which provides a little higher value.

Though the country possesses a substantial amount of water resources little has been developed for drinking water supply, hydropower, agriculture and other purposes. The water supply coverage was estimated to be 30.9 percent, thus the rural water supply coverage being 23.1 percent and that of urban being 74.4 percent (UNESCO 2004). PASDEP envisages that the unserved population will be reduced to 15.5 percent by 2009/10 showing more people being served than planned by MDG (Millennium Development Goals) by year 2015. The goal during PASDEP is also to reduce the share of malfunctioning rural systems from 30 percent in 2005/06 to 10 percent by 2010 (MOFED 2006). The great majority of the rural Ethiopian population community water supply relies on groundwater. The safe supply of water in rural areas is usually derived from shallow wells, spring development and deep wells. People who have no access to improved supply usually obtain water from rivers, unprotected springs, hand-dug wells and rainwater harvesting. Despite its immense relevance and importance, the groundwater sector has been given less attention until recently.

In order to utilize the ground water resource properly, understanding of the groundwater occurrence and distribution in space and time, proper management and efficient exploitation is necessary. The available studies on the groundwater resources of the country are very limited, in that, the delineation of aquifer systems, the water balance and determination of the aquifer characteristics has not been conducted. Any sustainable utilization of groundwater resources demands systematic study and raising the technical and manpower capability. In this regard the country has a long way to go, yet.

The conditions of sanitation are even worse in Ethiopia. The sanitation coverage in the capitalAddis Ababa, which is believed to have better service, was estimated at 12.5 percent (MoH and World Development Report 1997). The welfare monitoring survey (CSA 1998) pointed out that, out of this, 11 percent of the households have flush toilet, 73.3 percent of the households have pit latrine, 3.1 percent of the households use household containers,10.5 percent of households use open defecation (field and forest) and 2.2 percent of the households use other means. Re-use of treated waste water could provide an additional potential of water for irrigation.

Ethiopia’s energy sector, like in many other Sub-Saharan countries, depends highly on biomass despite the immense hydro-power resource of the country. According to Halcrow and MCE (2006),in 2000, 73.2 percent of energy came from woody biomass, 15.5 percent from non-woody biomass (cow dung 8.4 percent, crop residue 6.4 percent, and bio-gas 0.4 percent), petro fuels 10.3 percent and hydropower 1 percent. These are used in households, agriculture, transport, industry, service and others. By end of 2005, over 95 percent of the 1 percent of total energy coming from electricity was generated by hydropower. According to Beyene and Abebe (2006), the Interconnected System

(ICS), amounts to 769 MW, coming from 8 hydro, 5 diesel-powered and 1 geo-thermal plants, and the Self-Contained System (SCS) amounts to 23 MW coming from 3 small hydro and several small diesel plants, which brings the total electrical energy generation of 791 MW. The gross hydropower potential of the country is estimated at 650 Terra Watt Hour (TWh)/year. Out of this potential, about 160 TWh/year is believed to be technically and economically exploitable. However, the total installed capacity of the ICS and SCS is 791 MW, which is less than 2 percent of the potential.

The existing transmission system voltage in the ICS is 230 KV. According to MoFED 2006, the government having recognized the power shortage and its role in the economic development of the country is developing a number of hydropower projects. In total, generating capacity is to be increased to about 2,218 MW during PASDEP period (2009/10). The achievement of this is well underway from the existing systems which are under construction of large and medium-hydropower construction projects.

Based on the present indicative information sources, the potential irrigable land is about 3.7 million hectares. This figure is believed to be on a lower side, and could change as more reliable data emerge particularly on small-scale irrigation potential. Section “Irrigation Potential in River Basins of Ethiopia”, is fully devoted to the irrigation potential of Ethiopia. The area under irrigation development to-date, obtained from different sources is estimated to range between 160,000 – 200,000 hectares. At present some 197,000 hectares of land is under irrigation Solomon 2006. Estimates of the irrigated area presently vary, but range between 150,000 and 250,000 hectares less than five percent of potentially irrigable land (Werfring 2004; Awulachew et al. 2005). In this project, we have developed a database, as a starting point of shared information. Estimates of the irrigated area according to this database (based on the data reported by the MoWR), is 107,265.65 hectares, which is less than 5 percent of the potential. This database does not contain schemes which are under construction, or inoperational/suspended for some reasons. Details of the irrigation development are provided in the section “Irrigation Development in Ethiopia”.

The above figures clearly indicate the extent and magnitude of the need for accelerated development and management of the available water resources of the country. Hence, given the rapidly growing population in the foreseeable future, these resources will have to be tapped and harvested in order to attain food security, overcome the effects of climate change and variability, maintain sustainable industrial growth and improve the overall standard of living of the people of Ethiopia.

Constraints of Water Resources Development in Ethiopia are numerous. They fall in one of the general categories of legal, political, social, institutional or technical. These require careful consideration and need to be supported by applied research if the required level of development is to be ensured.

Increasing the role of applied research is one of the means to alleviate the problems encountered in the water sector. Irrigation and drainage research is considered as part and parcel of water resources research. Significant research activities have not yet been undertaken on irrigated crops.

This is because, unlike the agricultural and health sectors, institutionalized water research in Ethiopia does not exist, as it is the case in most parts of Africa and underdeveloped countries.

Irrigation potential in river basins of Ethiopia

Summary of potential

In Ethiopia, under the prevalent rainfed agricultural production system, the progressive degradation of the natural resource base, especially in highly vulnerable areas of the highlands coupled with climate variability have aggravated the incidence of poverty and food insecurity. Water resources management for agriculture includes both support for sustainable production in rain-fed agriculture and irrigation (Awulachew et al. 2005). Not overlooked should be soil protection and maintaining soil fertility.

Currently, the MoWR (Ministry of Water Resources) has identified 560 irrigation potential sites on the major river basins. The total potential irrigable land in Ethiopia is estimated to be around 3.7 million hectares.

( Source: working paper published by the international water management Institute, IWMI.)



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