ABSTRACT
ABSTRACT: The city of Addis Ababa has a population of over 4 million of which 50% have no direct access to the Municipal water supply system – a combination of surface water and groundwater. Pollution of fresh water resources is currently one of the major problems faced by the Addis Ababa residents and Municipality decision makers. Fast population growth and rapid industrialization, on one hand, and lack of sewerage network and poor living condition, on the other, have led to the progressive deterioration of surface and groundwater quality across the city. Of particular concern is the widespread use of septic tanks, open dumps, land applications and surface impoundments to dispose of waste. Direct discharge of domestic and industrial wastes into water bodies have increased the level of undesirable constituents in rivers, streams, and groundwater reservoirs. Chemical and bacteriological analyses reveal that constituents such as ammonia, nitrate, chloride, and extremely high total coliform concentrations in the surface water have been introduced through anthropogenic activities. The high degree of hydraulic connection between surface water and groundwater means that the volcanic aquifer is vulnerable to pollution. Therefore, controlling the quality of surface water is important to reduce long lasting impact on groundwater quality and maintain good quality water supply.
