Literature Review Ethiopia: Water Resources, Sanitation Coverage and Urbanizatio
Surface Water Resource
Ethiopia is one of the African countries endowed with rich water resources. The aggregate annual runoff from nine river basins in Ethiopia amounts to 122 billion cubic meters of water, on a catchment area of 1,136,816 Km2. The three largest river basins, the Abbay, Baro-Akobo, and Omo–Gibe contribute 76% of the total runoff from a catchment area comprising only 32% of the total area of the country (MoWR, 2001a). These major rivers have an average flow ranging from 30 to 500 m3/sec (Tamiru, 2006). The surface water resource is considered to be distributed unevenly, both spatially and temporally.
Between 80 to 90% of the surface water resource is found in the four river Basins, Abay (Blue Nile), Tekeze, Baro-Akobo, and Omo-Gibe in the west and south western part of the country. Thirty to forty percent of the population live in this area, while, the rest of the population, about 60%, live in the eastern and central river basins. In these areas the river basins contribute only 10-20 % of the total water resource (MoWR, 2001a). Over 84% originating in the country is trans-boundary and flows to other countries and is thus lost to Ethiopia (Mekonnen et al, 2001).
Because of the abundant surface water resources in Ethiopia, a comparatively lesser weight has been given to groundwater utilization. This is reflected in the fact that, to date, little is known of the total potential of groundwater resources both in terms of total potential and spatial distribution (Abera, 2001).
Although sporadic in nature, there are records of attempts at assessing groundwater resources in Ethiopia. In the 1950s a US Technical project support team carried out studies on the development of water supply for the principal cities of Ethiopia. The study also included determining appropriate location of industrial plants and sources of municipal water supply. This appears to have been with the intention of protecting water resources from potential pollution (CoC, 1954). A comprehensive survey of the underground and surface water resource of Ethiopia was also authorized at that time, with much less emphasis placed on waste water drainage (CoC, 1954).
Recent estimates of groundwater potential were made by Zewde (1994). He suggested that the total replenishable groundwater potential of Ethiopia, which could be technically developed for consumption purposes, is about 2.6 billion m3. Anecdotal evidence suggests that this was an approximation only and was not related to any investigation. This paucity of data has understandably originated from the absence of geological/hydro-geological studies in the country.
The total number of boreholes in the country is also not accurately known. In the period 1975-1982, for instance, Zewde (1994) records that a total of 1,018 deep wells were drilled or hand dug and 31 springs were developed in the country. This figure is now believed to have increased to over 10,000 (Addis Zemen, 2009). Nonetheless data on only 3,779 are documented so far. An inventory on updating this database is now being carried out, in cooperation with the Ministry of Water Resources, the Ministry of Mining and Energy, Addis Ababa University, and the US Geological Survey (Addis Zemen, 2009).
Water Supply Provision
Provision of clean water remains a major challenge in many countries and particularly in Africa. Globally clean water supply coverage has seen an increase from 78% in 1990 to 83% in 2004. This implies that more than 1.2 billion people gained access to improved drinking water sources over that period (UNICEF, 2006). In sub-Saharan countries the provision of clean water remains one of the challenges faced by many nations including Ethiopia.
Sub-Saharan Africa represents about 11% of the world‟s population, but almost a third of all people without access to safe drinking water live there. The urban–rural divide in drinking water is at its widest in this region. In this region 81% of people in urban areas are served, compared with 41% in rural areas (UNICEF, 2006).
This suggests that many sub-Saharan countries have to more than double their efforts in order to reach the Millennium Development Goals (MDGs) set by the United Nations. The MDGs aims to halve, by 2015, the proportion of people without sustainable access to safe drinking water and basic sanitation (UNICEF, 2006). If the current trend continues, sub-Saharan Africa will end up with 47 million more people un-served than in 2004 (UNICEF, 2006).
Although these efforts have been partly hampered by the rapid population growth, Ethiopia has managed to improve the level of water supply coverage over the previous decades. Ethiopian National statistics indicate that access to clean water supply increased from 23% to 41.2% in rural areas and from 74% to 80.3% in urban areas during the period 2002 to 2006. At the national level access to potable water had reached 47.3% by the end of 2006 and about 53% by the end of 2007 (MoFED, 2007b). The state of water provision in 2006 and 2007 is depicted in figure 2.1.
One possible reason for the low rural coverage is attributed to inoperative boreholes. Of the national total rural water supply schemes such as springs, hand pumps and boreholes developed, 26% have been reported to be non-functional and hence contributing to a shortfall in supply schemes (DHV, 2003). This figure has now dropped to 20% in 2007 (MoFED, 2007a) In terms of water supply, per capita consumption is still considered to be low. In 2003, the average per capita consumption of water in urban areas in Ethiopia was reported to be 15 litres/capita/day (DHV, 2003). This is consistent with the CSA (2005) survey in selected towns which also indicated a per capita consumption of 14.8 litres per day. It is however, a significant reduction from the 30 litres per capita per day reported in 1969 in the city of Addis Ababa. At that time the annual rate of growth of water demand was estimated to be 9% over the previous years (BCEOM, 1970).
One of the reasons for the low water consumption is thought to be the high initial cost of private house connections (DHV, 2003) and the cost of collecting it from sources outside the house. In 2007 more than 82% were accessing water within a distance of one Km (MoFED, 2007b). With the current economic growth, life style changes and the increasing number of new housing with interior plumbing, demand for more potable water is expected to rise. According to the Water Sector Master Plan Study, future demand is projected to increase as indicated in the following table.
To meet this rising demand, considerable financial resources will be needed. At the national level it is estimated that a total investment of up to 11.9 billion birr will be required to bring the level of all urban areas water supply coverage to 100% by the year 2025. Rural areas would also require a significant amount of financing to achieve even a modest 60% coverage by the year 2025 (DHV, 2003). Faced with this demand, it is inevitable that extra resources will need to be tapped and utilized. As developing surface water for drinking purposes would entail significant amount of investment and longer time of implementation, the trend in Ethiopia and particularly in Addis Ababa, has been the utilization of groundwater resources.
Groundwater utilization is increasing worldwide (Zaporozec & Miller, 2000). In the United States groundwater is the source of domestic water supply for almost 90% of the rural population and for about 50% of the urban population (Power & Schepers, 1989). In Denmark, West Germany, the Netherlands and Great Britain groundwater accounts for 99, 73, 70, and 30%, respectively, of the total water consumption (Strebel, Duynisvel, & Bottcher, 1989).
In Ethiopia a majority of the population utilizes springs and shallow wells as the main source of potable water. In almost all of the 10 river basins in the country deep and shallow groundwater is the main source of potable water. About 80% of towns use groundwater sources (DHV, 2003). In 2006 the Federal Ministry of Health (2006) indicated that, 8.4% of the urban and 56.8% of the rural population of the country utilize groundwater sources for potable water consumption. In the city of Addis Ababa it is estimated that about 40% of the total water supply originates from groundwater sources in and around the city. Recent efforts to boost water supply to the city have also focused on developing new wells.
At the national level, a water supply and sanitation master plan covering a development scenario up to 2025 envisages the construction of more than 60,000 schemes, the majority of which include hand dug wells and springs development (DHV, 2003). Groundwater abstraction for consumption purposes will therefore continue to rise due to increased population and the associated demand. In general however the geology of the country is not favourable for the efficient use of groundwater resources due to excessive extraction costs (DHV, 2003).
1.2. The Study Area
1.3. Ethiopia: Location and General Data
1.5. Aims and Objectives of the Thesis
1.6. Data Collection and Processing
1.7. Layout of the Thesis
2. Literature Review
2.1. Ethiopia: Water Resources, Sanitation Coverage and Urbanization
3 The Study Area
3.1 The city of Addis Ababa
3.2 Addis Ababa: Location and History
3.3 Addis Ababa: Climate, Population and Growth
3.4 Addis Ababa: Geology
3.5 Addis Ababa: Hydrogeology
3.6 Main Aquifers in Addis Ababa
3.7 Addis Ababa Water Resources and Supply
3.8 Water Wells Inventory in Addis Ababa
3.9 Addis Ababa Sanitation Service Coverage
3.10 Contaminant Chemicals in Pit Latrines
3.11 Groundwater Quality in Addis Ababa
3.12 Sanitation and Health
4. Research Process, Methodology and Data Collection
4.1. The Research Process
4.2. Data Collection
4.3. Types of Data Collected
4.4. Data Collection Process
4.5. Shortcomings on Data Collected
4.6. Data Evaluation Methodology
4.7. Results of Data Evaluation
5 Distribution and Extent of Low-cost Sanitation Waste Load on Aquifers
5.1 Estimation of Pit latrines density in Addis Ababa
5.2 Spatial distribution of pit Latrines in Addis Ababa
5.3 Low- Cost Sanitation as Diffuse Sources of Pollution
5.4 Aquifers Vulnerability
5.5 Estimation of pollution load on groundwater resource
6 Degree of Nitrate Contamination: Temporal Variation
6.1 Variation of Nitrate and Chloride in Minor Aquifers 1977-2009
6.2 Variation of Nitrate and Chloride in Major Aquifers 1978-2008
6.3 Temporal patterns of Nitrate and Chloride in Aquifers
6.4 Minor Aquifer Springs
6.5 Faecal Contamination Indicators
6.6 Variation of Nitrate and, Chloride, with Depth of Wells
7 Spatial Extent of Groundwater Contamination
7.1 Minor Aquifers 2000 to 2008/09
7.2 Major Aquifers 2000 to 2008/09
7.3 Low- cost Sanitation and its Impact on Groundwater Quality
7.4 Environmental Impact of Low- cost Sanitation on Groundwater
7.5 Water Quality Impact on Minor Aquifers
7.6 Water Quality Impact on Major Aquifers
8 Environmental Policy and Sanitation and Groundwater Resource Management
8.1 Ethiopian Environmental Policy
8.2 Groundwater Management Strategy
9 Discussion of Findings
10 Conclusion and Recommendations
10.1 Summary and Conclusion
10.3 Issues for Further research
GET THE COMPLETE PROJECT